Air Compressors Info

Compressed Air Energy Storage (CAES)

2011-05-29T21:08:00.000+07:00

Compressed Air Energy Storage (CAES) is a way to store energy generated at one time for use at another time. At utility scale, energy generated during periods of low energy demand (off-peak) can be released to meet higher demand (peak load) periods.

Compression of air generates a lot of heat. The air is warmer after compression. Decompression requires heat. If no extra heat is added, the air will be much colder after decompression. If the heat generated during compression can be stored and used again during decompression, the efficiency of the storage improves considerably.

There are three ways in which a CAES system can deal with the heat. Air storage can be adiabatic, diabatic, or isothermic:

Adiabatic storage retains the heat produced by compression and returns it to the air when the air is expanded to generate power. This is a subject of ongoing study, with no utility scale plants as of 2010. Its theoretical efficiency approaches 100% for large and/or rapidly cycled devices and/or perfect thermal insulation, but in practice round trip efficiency is expected to be 70%. Heat can be stored in a solid such as concrete or stone, or more likely in a fluid such as hot oil (up to 300 °C) or molten salt solutions (600 °C).

Diabatic storage dissipates the extra heat with intercoolers (thus approaching isothermal compression) into the atmosphere as waste. Upon removal from storage, the air must be re-heated prior to expansion in the turbine to power a generator which can be accomplished with a natural gas fired burner for utility grade storage or with a heated metal mass. The lost heat degrades efficiency, but this approach is simpler and is thus far the only system which has been implemented commercially. The McIntosh, Alabama CAES plant requires 2.5 MJ of electricity and 1.2 MJ lower heating value (LHV) of gas for each megajoule of energy output. A General Electric 7FA 2x1 combined cycle plant, one of the most efficient natural gas plants in operation, uses 6.6 MJ (LHV) of gas per kW–h generated, a 54% thermal efficiency comparable to the McIntosh 6.8 MJ, at 53% thermal efficiency.

Isothermal compression and expansion approaches attempt to maintain operating temperature by constant heat exchange to the environment. They are only practical for low power levels, without very effective heat exchangers. The theoretical efficiency of isothermal energy storage approaches 100% for small and/or slowly cycled devices and/or perfect heat transfer to the environment. In practice neither of these perfect thermodynamic cycles are obtainable, as some heat losses are unavoidable.

A different, highly efficient arrangement, which fits neatly into none of the above categories, uses high, medium and low pressure pistons in series, with each stage followed by an airblast venturi pump that draws ambient air over an air-to-air (or air-to-seawater) heat exchanger between each expansion stage. Early compressed air torpedo designs used a similar approach, substituting seawater for air. The venturi warms the exhaust of the preceding stage and admits this preheated air to the following stage. This approach was widely adopted in various compressed air vehicles such as H. K. Porter, Inc's mining locomotives and trams. Here the heat of compression is effectively stored in the atmosphere (or sea) and returned later on.

Compression can be done with electrically powered turbo-compressors and expansion with turbo 'expanders' or air engines driving electrical generators to produce electricity.

The storage vessel is often an underground cavern created by solution mining (salt is dissolved in water for extraction) or by utilizing an abandoned mine. Plants operate on a daily cycle, charging at night and discharging during the day.

Compressed air energy storage can also be employed on a smaller scale such as exploited by air cars and air-driven locomotives, and also by the use of high-strength carbon-fiber air storage tanks.

Source: http://en.wikipedia.org/wiki/Compressed_air_energy_storage

Theory of air compression 2

2011-05-02T00:13:00.000+07:00

An air compression is a means by which one type of energy is converted to another. During this conversion certain losses occur because of the rise in temperature of the air as it compressed. In general practice, the air is stored in a receiver and heat is lost both in the receiver and pipe lines running to equipment. Since the rise in temperature of the air is a direct loss of energy. We want to keep it down to a minimum. The ideal method is to compress air isothermally but this is impossible in practice owing to lack of time necessary to affect transfer.
Water jackets and inter-cooling can be used to keep the temperature down. These have the effect of reducing the compression index (n) to something less than 1.4.

When air is compressed to a pressure to exceeding about 4 bar it is usual to compress it in stages, with intercooling between each stage. This considerably reduces the total amount of work required on the air.
For two stages compressing, the air is compressed in the first (low pressure) stage adiabatically from p1 to p2 and then enters the intercooler where it is cooled down to the original temperature. Its volume is thereby reduced to V2 which is on the isothermal line. This volume of air now enters the high pressure cylinder, and is compressed to the final pressure and volume (p3 and V3). The law of compression is assumed to be the same for both compressors, namely:

p Vⁿ = C

The pressure of intercooling to give the minimum of work done is when:
p2 = sqrt(p1 x p3)

Compression may be done in three or more stages to reduce the amount of work. Multistage compression approaches isothermal compression as the number of stages is increased.

Theory of air compression

2011-05-01T11:36:00.002+07:00

Air is not a perfect gas but for practical purpose the laws relative to perfect gases may be applied to it.

Boyle’s law states that: The absolute pressure of a gas varies inversely as the volume, provided the temperature remains constant.

p V = a constant

where: p = pressure in bar, V = volume in m³.

Charles’ law states that the volume of a gas under constant pressure, or the pressure of a gas under constant volume, varies as the absolute temperature. Therefore V varies as T, and p varies as T where T is the absolute temperature.

If the two laws are combined, we get:

p V / T = constant

The constant is usually denoted by R and therefore:
p V = R T

It can be shown that the value of the constant R applicable to air is 287.0 J/(kg K).
The relation between the pressure and volume of air during its expansion and compression may be represented by:

p Vⁿ = R T

where ‘n’ has value which depends on the addition or subtraction of heat during the process.
When the temperature remains constant during compression or expansion they is said to be isothermal and the value of ‘n’ is one. In order to obtain pure isothermal compression it would be necessary to remove heat from the air at the same rate as heat is produced by the work done on the gas. When a gas expands and when no heat passes during expansion or contraction they is said to be adiabatic.

Opportunity of Compressed Air Savings

2011-04-30T23:35:00.000+07:00

Approximately 10 % of all electrical power used in industry comes from compressed air. This is proof of its widespread usage but it is also evidence of the potentially large saving in costs which could be achieved if the energy management opportunities are put into practice.

Normally, the purpose of compressed air systems in the industrial sectors is to deliver the necessary volume of air at the required pressure and temperature to the correct places. Compressed air is used for operating pneumatic equipments, cleaning purposes, and other general services. This is accomplished by a distribution system consisting of pipes, valves and fittings. The Compressed Air pipe work is arranged in the form of ring mains with interconnections to points of end-users.

Careful evaluation of existing compressed air systems can ensure against improper operation, and poor energy utilization. Alert design, operations, and maintenance personnel, with an awareness of energy management, can achieve significant savings in areas such as:

Detection and elimination of leaks.
Reduction of friction losses and the associated pressure drops.
Application of new technology.

Compressed Air System Energy-Reduction Case Study (Part 2)

2011-04-08T18:50:00.005+07:00

Let's continue from [Compressed Air System Energy-Reduction Case Study (Part 1)]

Compressed Air Energy-Reduction Strategy

Project Goals and Implementation

Following the IAC assessment, FUJIFILM’s maintenance team formulated project goals and an implementation plan that centered on the utilization of existing facility infrastructure and equipment. The team’s implementation strategy was divided into three phases and focused on increasing the system’s storage capacity to handle production peaks and valleys; lowering air compressor operating pressure; repairing system leaks; and ultimately, operating the facility with one compressor. The team’s strategy was also aided by the company’s closure of its Orange Park, Florida, operations. This facility housed a 75 horsepower (HP) air compressor, a dryer, and a receiver, which the Dayton facility incorporated into its efforts.

Project success, then, depended on the accomplishment of four specific goals:

To increase system redundancy, therefore increasing
system reliability
To reduce system maintenance costs
To reduce overall facility energy use
To eliminate the use of nitrogen when compressed air
systems are down.

Phase I
Phase I was justified using maintenance-cost-reduction estimates. Labor was billed as a maintenance expense to the existing budget. During this phase, the facility installed Orange Park’s 75 HP air compressor in Building 5, a receiver in Building 6, and a 2-inch airline from Building 5 to Building 6. The 60 HP air compressor in Building 6 was then shutdown for repair and established as a backup unit. The building’s piping was also combined with its heat installation. Phase I was completed in May 2008.

Phase II
The Dayton facility justified Phase II to FUJIFILM Corporate by utilizing total project energy-saving estimates. During this phase, piping was installed from Building 5 to Buildings 1 and 6, and an additional receiver was installed in Building 1. The existing 50 HP air compressor and dryer in Building 1 were
shutdown for maintenance and repair and established as a backup unit. This established the 75 HP air compressor in Building 5 as the facility’s central unit. Phase II was completed in March 2009.

Phase III
During Phase III, the maintenance team developed and implemented a Leak Detection and Repair (LDAR) program (completed in the fall of 2009), and developed a quarterly preventative maintenance program to repair system leaks and reduce the amount of compressed air losses. Additionally, the facility gathered data that indicated a 2 PSIG drop in pressure resulted in a 1% reduction in cost. The team reduced compressor set pressure to 105 PSIG, which resulted in POU delivery of 98 PSIG.

Source: http://www1.eere.energy.gov/industry/saveenergynow/pdfs/fujifilm_case_study.pdf

Compressed Air System Energy-Reduction Case Study (Part 1)

2011-04-07T18:39:00.000+07:00

FUJIFILM Hunt Chemicals U.S.A. Achieves Compressed Air System Energy-Reduction Goals with a Three-Phased Strategy.

In an attempt to eliminate equipment failures and downtime issues associated with the plant’s compressed air system, FUJIFILM Hunt Chemicals U.S.A.’s in-house maintenance team worked with a team of faculty and students from the Tennessee Technology University Industrial Assessment Center (IAC) to conduct an assessment at its Dayton, Tennessee, facility to identify opportunities for improvement. Following the assessment, the team formulated an implementation plan that would increase the system’s reliability, reduce system maintenance costs, reduce the facility’s overall energy use, and eliminate the use of nitrogen when compressed air systems are down.

The Energy Situation
The Dayton facility was experiencing excessive downtime due to chronic air compressor failures and significant inefficiencies throughout its compressed air system. In 2007 alone, system operating costs totaled over $45,000, with maintenance and repair costs exceeding $17,000. The problems FUJIFILM was experiencing were also causing frequent interruptions in the facility’s production operations. Due to the nature of these operations, the facility could not afford to experience the downtime required to complete compressed air system maintenance. The facility was depending on a backup operating system that relied on the utilization of onsite nitrogen, which is normally reserved for processing flammable materials. While maintenance staff were certified in both quality and environmental-management systems—ISO 9001 and 14001 standards, respectively—they lacked the parts and system expertise needed to effectively support the
compressed air generating equipment.

Additional Costs Incurred with Old Compressed Air Scheme:

Maintenance = $1,296
Nitrogen Backup = $7,921
Repair = $7,877
TOTAL = $17,094

Furthermore, the frequency of equipment failures indicated inherent and systemic inefficiencies, including unutilized capacity generation and overstated requirements. These issues led the facility Maintenance Manager, Manuel Calero, and his team to partner with the Tennessee Technology University IAC, sponsored by the U.S. Department of Energy’s Industrial Technologies Program (ITP), to conduct an overarching assessment of the Dayton facility’s compressed air system. ITP’s IAC program provides eligible small- and mid-sized manufacturing plants with no-cost energy assessments. In 2008, a team of engineering and technology students and faculty from Tennessee Technology University visited the Dayton plant to conduct the compressed air system assessment to identify potential savings opportunities.

Developing a Baseline
The IAC and in-house maintenance team’s first step was to baseline the system’s demand-side air requirements to determine the system’s actual efficiency. The site’s original compressed air system scheme consisted of two Ingersoll Rand air compressors, located in Buildings 1 and 6.1 Compressed air in these buildings was used in a variety of processing operations that facilitated material delivery through a system of pipelines. Major uses of the air included the operation of pneumatic control devices, such as actuator valves and cylinders, and liquid transfers via air diaphragm pumps to appropriate storage tanks. These transfer rates
were critical to maintaining quality in both the process and product. To establish the baseline, the IAC team calculated the cost of air production; gathered initial measurements of energy, flow, pressure, and leak load; and estimated energy consumption, which was then correlated to the appropriate production levels. The team also conducted energy surveys with the assistance of Ingersoll Rand. This effort required connecting amp and flow meters to each compressor for five days. This allowed the facility to accurately assess energy versus standard cubic feet per minute generated and used. Results of the assessment showed that both facility compressors were set to run at 120 pounds per square inch (PSIG), but were only delivering between 90 to 95 PSIG at point of use (POU), and were, at times, dropping as low as 80 PSIG. Additional findings demonstrated that higher air use was occurring during transfers—as opposed to reactions—and that the system’s air use was cyclical, depending on production. It was also confirmed that Production Line 1 had
excess capacity. The compressed air distribution system also contained significant leaks. A concurrent review of existing system dryers indicated subpar performance and explained undue levels of moisture in the system. Most importantly, though, the data indicated that the Dayton facility could be operated using only one compressor.

Read more details in [Compressed Air System Energy-Reduction Case Study (Part 2)]

Stabilizing System Pressure

2011-04-06T15:27:00.002+07:00

Stabilizing system pressure is an important way to lower energy costs and maintain reliable production and product quality. The need to stabilize system pressure should be guided by the compressed air demand patterns and the minimum acceptable pressure level required for reliable production. High-volume intermittent air demand events can cause air pressure to fluctuate, which is often misinterpreted as insufficient pressure. In some cases, improperly set compressor controls will cause another compressor to start, but because of the time required for the new compressor to ramp up, there will be a shortfall of air supply to the system. Such a delay can cause the system pressure to decay, resulting in lost production. Three methods can be used to stabilize system pressure: adequate primary and secondary storage, Pressure/Flow Controllers (P/FCs), and dedicated compressors.

Primary and Secondary Storage

One or more compressed air applications having large, intermittent air demands can cause severe, dynamic pressure fluctuations in the whole system, with some essential points of use experiencing inadequate pressure. Such demand is often of short duration; properly sized primary and secondary storage can supply the needs of the intermittent demand. The time interval between the demand events is adequate to restore the storage receiver pressure without adding compressor capacity. Primary storage receivers can:

Prevent frequent loading and unloading of compressors
Collect condensate, which may be carried over from the aftercooler and moisture separator
Provide some radiant cooling to reduce moisture content and air dryer load if located in a cool location and installed upstream of the dryer
Provide dampening of pressure pulsations from reciprocating compressors.
Secondary storage receivers can be used to:
Supplement the primary receivers to stabilize system pressure and thus keep unneeded compressors from starting
Supply adequate compressed air for a single intermittent event of a known duration.

The secondary receiver should be located as close to the end use as is practicable and its pressure rating must be at least equal to that of the primary receiver(s).

Pressure fluctuations may also occur due to inadequate storage or because the system pressure is at or near the lowest level of the compressor pressure control band. If a large, intermittent demand event occurs when the pressure is at or near the lowest level in the control band, the pressure in the distribution piping falls even further, affecting critical end-use applications. In such a case, the installation of a relatively small receiver with a check valve upstream of the application causing the demand event may address the problem.

Pressure/Flow Controllers

A Pressure/Flow Controller (P/FC) is a device that serves to separate the supply side of a compressed air system from that system’s demand side. P/FCs use the principle of operating compressors to fi ll and store air in receivers at higher pressures. P/FCs then reduce the pressure and supply it to the system at the pressure required by that system’s compressed air applications. P/FCs work with pilot-operated regulators or electronic controls to sense and monitor the system’s pressure downstream of the valves. Controlled pressure and adequate upstream storage are critical to satisfactory performance. P/FCs normally respond rapidly to demand fl uctuations and maintain system pressure within a narrow band. For peak demand events, suffi cient storage is necessary to release the stored air quickly into the system to maintain required downstream pressures within an acceptable tolerance. With proper design and system controls, storage can be used to meet air demand and reduce compressor run time.

Dedicated Compressors

Applications some distance from the main compressor supply or those with pressure requirements that differ from the main system requirements may be served by a dedicated compressor. Small or unit type compressors (generally up to 10 hp maximum) can be very suitable for an application whose pressure level is higher than that of the plant’s other applications. Generally, such compressors can be located close to a point of use, avoiding lengthy piping runs and pressure drops; are adaptable to a wide range of conditions such as temperature, altitude, and humidity; and do not require separate cooling systems.

Source: http://www1.eere.energy.gov/industry/bestpractices/pdfs/compressed_air8.pdf

Remove Condensate with Minimal Air Loss

2011-04-04T18:20:00.002+07:00

Removing condensate is important for maintaining the appropriate air quality level required by end uses. However, significant compressed air (and energy) losses can occur if condensate removal is done improperly.
Excess compressed air loss during condensate removal can occur due to several factors. Following shows several condensate removal methods and the characteristics of each method.

Manual operation:

Operators manually open valves to discharge condensate.
Depends on people opening valves at the appropriate time for the necessary amount of time.
Often leads to excess loss because air escapes when the valves are left open to drain the condensate.

Level-operated mechanical float traps:

Use a float connected by linkage to a drain valve that opens when an upper setting is reached and closes when the drain is emptied.
Require considerable maintenance.
Are prone to blockage from sediment in condensate.
Are prone to getting stuck in open position (leak excess air) and in the closed position (does not allow condensate to be drained).
Inverted bucket traps may require less maintenance, but will waste air if the condensate rate is inadequate to maintain the liquid level in the trap.
Most suited for a fully-attended powerhouse operation with scheduled maintenance.

Solenoid-operated drain valves:

Have timing devices that can be set to open for specified amounts of time at pre-set adjustable intervals.
The period during which the valve is open may not be long enough for adequate drainage of accumulated condensate.
The valve will operate even if little or no condensate is present, resulting in air loss.
Require strainers to reduce contaminants, which can block the inlet and discharge ports of these devices.

Zero-loss traps:

Have a float or level sensor that operates an electric solenoid or ball valve to maintain the condensate level in the reservoir below the high level point, or a float activates a pneumatic signal to an air cylinder to open a ball valve through a linkage to expel the condensate in the reservoir to the low level point.
Wastes no air.
Considered very reliable.
Reservoir needs to be drained often to prevent the accumulation of contaminants.

Other Points to Consider

Drain the condensate often and in smaller quantities rather than less frequently and in larger quantities. Consider oversized condensate treatment equipment to handle unexpected lubricant loading and to reduce maintenance. All drain traps should be inspected periodically, with parts repaired or replaced as required. If replacement is the decision, consider using zero loss drain traps.

Source: http://www1.eere.energy.gov/industry/bestpractices/pdfs/compressed_air13.pdf

Preventive Maintenance Strategies for Compressed Air Systems

2011-03-31T17:36:00.000+07:00

A brewery neglected to perform routine maintenance on its compressed air system for years. As a result, two of its centrifugal compressors, whose impellers had been rubbing against their shrouds, were unable to deliver the volume of air they were rated for and one of those units had burned up several motors during its lifetime. In addition, plant personnel did not inspect the system’s condensate traps regularly. These traps were of a type that clogged easily, which prevented the removal of moisture and affected product quality. Also, the condensate drains were set to operate under the highest humidity conditions, so they would actuate frequently, which increased the system’s air demand. As a result, energy use was excessively high, equipment repair and replacement costs were incurred unnecessarily, and product quality suffered. All of this could have been avoided through regular maintenance.

Like all electro-mechanical equipment, industrial compressed air systems require periodic maintenance to operate at peak efficiency and minimize unscheduled downtime. Inadequate maintenance can increase energy consumption via lower compression efficiency, air leakage, or pressure variability. It also can lead to high operating temperatures, poor moisture control, excessive contamination, and unsafe working environments. Most issues are minor and can be corrected with simple adjustments, cleaning, part replacement, or elimination of adverse conditions. Compressed air system maintenance is similar to that performed on cars; filters and fluids are replaced, cooling water is inspected, belts are adjusted, and leaks are identified and repaired.

A good example of excess costs from inadequate maintenance can be seen with pipeline filter elements. Dirty filters increase pressure drop, which decreases the efficiency of a compressor. For example, a compressed air system that is served by a 100-horsepower (hp) compressor operating continuously at a cost of $0.08/kilowatt-hour (kWh) has annual energy costs of $63,232. With a dirty coalescing filter (not changed at regular intervals), the pressure drop across the filter could increase to as much as 6 pounds per square inch (psi), vs. 2 psi when clean, resulting in a need for increased system pressure. The pressure drop of 4 psi above the normal drop of 2 psi accounts for 2% of the system’s annual compressed air energy costs, or $1,265 per year. A pressure differential gauge is recommended to monitor the condition of compressor inlet filters. A rule of thumb is that a pressure drop of 2 psi will reduce the capacity by 1%.

All components in a compressed air system should be maintained in accordance with the manufacturers’ specifications. Manufacturers provide inspection, maintenance, and service schedules that should be strictly followed. Because the manufacturer-specified intervals are intended primarily to protect the equipment rather than optimize system efficiency, in many cases, it is advisable to perform maintenance on compressed air equipment more frequently.

One way to tell if a compressed air system is well maintained and operating efficiently is to periodically baseline its power consumption, pressure, airfl ow, and temperature. If power use for a given pressure and flow rate increases, the system’s efficiency is declining. Baselining the system will also indicate whether the compressor is operating at full capacity, and if that capacity is decreasing over time. On new systems, specifications should be recorded when the system is fi rst installed and is operating properly.

Types of Maintenance

Maintaining an air compressor system requires caring for the equipment, paying attention to changes and trends, and responding promptly to maintain operating reliability and effi ciency. To assure the maximum performance and service life of your compressor, a routine maintenance schedule should be developed. Time frames may need to be shortened in harsher environments. Proper maintenance requires daily, weekly, monthly, quarterly, semi-annual, and annual procedures. Please refer to the Compressed Air System Best Practices Manual for the types of procedures that are relevant to the compressors and components in your system. Excellent maintenance is the key to good reliability of a compressed air system; reduced energy costs are an important and measurable by-product. The benefi ts of good maintenance far outweigh the costs and efforts involved. Good maintenance can save time, reduce operating costs, and improve plant manufacturing efficiency and product quality.

Source: http://www1.eere.energy.gov/industry/bestpractices/pdfs/compressed_air6.pdf

Maintaining System Air Quality

2011-03-29T17:27:00.000+07:00

"Maintaining the proper air quality level is essential for keeping compressed air energy costs down and to ensure reliable production."

Poor air quality can have a negative effect on production equipment and can increase energy consumption and maintenance needs. The quality of air produced should be guided by the quality required by the end-use equipment. The air quality level is a function of the levels of particulate, moisture, and lubricant contaminants that the end uses can tolerate. Such air quality levels should be determined before deciding whether the air needs additional treatment. Compressed air should be treated appropriately but not more than is required for the end-use application. The higher the quality, the more the air usually costs to produce (in terms of initial capital investment in equipment, energy consumption and maintenance).

Once the true end-use air quality requirements have been determined, the proper air treatment equipment can be configured. Separators, filters, dryers and condensate drains are used to improve compressed air quality. Treatment equipment maintenance is critically important for sustaining the desired air quality levels.

Grouping Equipment with Similar Air Quality Requirements
One strategy to improve air quality is to group end uses having similar air quality requirements in reasonably close proximity and install the appropriate air treatment equipment to serve these end uses with a minimum of distribution piping. Some-times, grouping similar requirements of best quality air together is not always practical; if the requirement for this class is sufficiently high (70% or more of total), consider supplying the entire plant with this air quality level. If practical, separation of groups of end uses requiring similar pressure and air quality also allows some compressors and air treatment equipment to be located close to the end uses.

Filtration
Through proper filtration, appropriate air quality levels can be achieved. Because some end uses may require a higher level of air quality than others, it may not be necessary to have the entire airflow filtered to the highest level of air quality. Filters cause pressure drop that increases as the elements become fouled. Filters should be rated for the maximum anticipated operating pressure, but should be sized for the maximum anticipated rate of flow at the anticipated minimum operating pressure. The three types of compressed air filters (particulate, coalescing, and adsorption) have different functions and must be selected for the appropriate application.

Dryers
Compressed air dryers can be very effective at removing condensate from compressed air. Dryers are of three types: deliquescent, refrigerated, and desiccant. Deliquescent dryers provide a Pressure Dew Point (PDP) of 20°F lower than the dew point of the air entering them. Refrigerated dryers provide a PDP of between 35°F and 38°F and desiccant dryers can provide a PDP as low as -100°F. Dryers should be sized for the maximum anticipated rate of fl ow and must be matched to the air quality requirements. Overdrying wastes energy.

Separators
Moisture separators and condensate traps are used to remove condensate from the air stream. Because the fi rst step in condensate removal is to separate it from the air stream, moisture separators should follow each intercooler and aftercooler.

Condensate Traps
There are four main types of condensate drains: manual, level-operated mechanical (fl oat) traps, electrically-operated solenoid valves and zero-loss traps with reservoirs. Traps should allow removal of condensate, but not compressed air, and should not be left open.

Source: http://www1.eere.energy.gov/industry/bestpractices/pdfs/compressed_air12.pdf

Engineer End Uses for Maximum Efficiency

2011-03-28T17:20:00.000+07:00

Compressed air is one of the most important utility requirements of many industrial manufacturing plants because it directly serves processes and applications such as pneumatic tools, pneumatic controls, compressed air operated cylinders for machine actuation, product cleansing and blow-off applications. Ensuring an appropriate, stable pressure level at the end-use applications is critical to the performance of any industrial compressed air system. End uses that are engineered for maximum efficiency can help provide the consistent supply of compressed air that ensures reliable production.

To ensure the efficiency of compressed air end-use applications, a number of steps should be taken:

Review the pressure level requirements of the end-use applications. Those pressure level requirements should determine the system pressure level. Because there is often a substantial difference in air consumption and pressure levels required by similar tools available from different manufacturers, request exact figures from each manufacturer for the specific application. Do not confuse maximum allowable with required pressure.
Monitor the air pressure at the inlet to the tool. Improperly-sized hoses, fittings and quick disconnects often result in large pressure drops. These drops require higher system pressures to compensate, thus wasting energy. Reduced inlet pressure at the tool reduces the output from the tool and, in some cases, may require a larger tool for the specified speed and torque.
Avoid the operation of any air tool at “free speed” with no load. Operating a tool this way will consume more air than a tool that has the load applied.
Check the useful life of each end-use application. A worn tool will often require higher pressure, consume excess compressed air, and can affect other operations in the immediate area.
Air tools should be lubricated as specified by the manufacturer, and the air going to all end uses should be free of condensate to maximize tool life and effectiveness.
End uses having similar air requirements of pressure and air quality may be grouped in reason-ably close proximity, allowing a minimum of distribution piping, air treatment, and controls.
Investigate and, if possible, reduce the highest point-of-use pressure requirements. Then, adjust the system pressure.
Investigate and replace inefficient end uses such as open blowing with efficient ones such as vortex nozzles.

Case Study: A New Compressed Air Application is Configured for Maximum Efficiency
A large, custom printing company installed a more technologically-advanced printing machine that could increase the output of its existing units. However, the initial configuration of the new printing machine more than doubled the compressed air demand of the entire site. After a thorough review, the plant personnel realized that it would be more cost-effective for the new machines to be redesigned to consume less air at lower pressures than to increase compressor capacity at all of the company’s printing plants. Once the printing machines were reconfigured, the total air demand per printing machine was reduced from 27 standard cubic feet per minute (scfm) to 4.5 scfm and the need for 100 pounds per square inch gauge (psig) compressed air was eliminated, resulting in substantial avoided costs in energy and capital expenditures.

Source: http://www1.eere.energy.gov/industry/bestpractices/pdfs/compressed_air10.pdf

Eliminate Inappropriate Uses of Compressed Air

2011-03-25T17:08:00.000+07:00

Compressed air generation is one of the most expensive utilities in an industrial facility. When used wisely, compressed air can provide a safe and reliable source of power to key industrial processes. Users should always consider other cost-effective forms of power to accomplish the required tasks and eliminate unproductive demands. Inappropriate uses of compressed air include any application that can be done more effectively or more efficiently by a method other than compressed air. The table below provides some uses of compressed air that may be inappropriate and suggests alternative ways to perform these tasks.

Potentially Inappropriate Uses could be replaced by following suggested alternatives:

Clean-up, Drying, Process cooling: Low-pressure blowers, electric fans, brooms, nozzles
Sparging: Low-pressure blowers and mixers
Aspirating, Atomizing: Low-pressure blowers
Padding: Low to medium-pressure blowers
Vacuum generator: Dedicated vacuum pump or central vacuum system
Personnel cooling: Electric fans
Open-tube, compressed air-operated vortex coolers without thermostats: Air-to-air heat exchanger or air conditioner, add thermostats to vortex cooler
Air motor-driven mixer: Electric motor-driven mixer
Air-operated diaphragm pumps: Proper regulator and speed control; electric pump
Idle equipment (Equipment that is temporarily not in use during the production cycle.): Put an air-stop valve at the compressed air inlet
Abandoned equipment (Equipment that is no longer in use either due to a process change or malfunction.): Disconnect air supply to equipment

Example
The table below shows inappropriate uses of compressed air in an automobile assembly plant. The plant took several action steps identified in the table to eliminate or reduce these inappropriate uses. Peak flow is identified in cubic feet per minute (cfm).

The plant audit showed that the energy used to generate the compressed air averages 18 kW/100 cfm. The aggregate electric rate at the plant is $0.05 per kWh.

Annual savings = [kW per cfm] x [cfm savings] x [# of hours] x [$ per kWh]

= 18/100 x [(150 x 6,500) + (1,000 x 5,000) + (800 x 3,500)
+ (750 x 3,500)] x $0.05
= $102,600

Net savings:
Calculate electric energy costs for the motor-driven vacuum pump, fans, and actuators, and subtract these costs from the annual savings calculated to determine the net savings. Note that there will be a one-time cost of installation for the added equipment.

Source: http://www1.eere.energy.gov/industry/bestpractices/pdfs/compressed_air2.pdf

Effect of Intake Air on Compressor Performance

2011-03-23T17:00:00.006+07:00

The effect of intake air on compressor performance should not be underestimated. Intake air that is contaminated or hot can impair compressor performance and result in excess energy and maintenance costs. If moisture, dust, or other contaminants are present in the intake air, such contaminants can build up on the internal components of the compressor, such as valves, impellers, rotors, and vanes. Such build-up can cause premature wear and reduce compressor capacity.

"When inlet air is cooler, it is also denser. As a result, mass flow and pressure capability increase with decreasing intake air temperatures, particularly in centrifugal compressors."

This mass flow increase effect is less pronounced for lubricant-injected, rotary-screw compressors because the incoming air mixes with the higher temperature lubricant. Conversely, as the temperature of intake air increases, the air density decreases and mass flow and pressure capability decrease. The resulting reduction in capacity is often addressed by operating additional compressors, thus increasing energy consumption.

To prevent adverse effects from intake air quality, it is important to ensure that the location of the entry to the inlet pipe is as free as possible from ambient contami-nants, such as rain, dirt, and discharge from a cooling tower. If the air is drawn from a remote location, the inlet pipe size should be increased in accordance with the manufacturer’s recommendation to prevent pressure drop and reduction of mass flow. All intake air should be adequately filtered. A pressure gauge indicating pressure drop in inches of water is essential to maintain optimum compressor performance.

When an intake air filter is located at the compressor, the ambient temperature should be kept to a minimum, to prevent reduction in mass flow. This can be accomplished by locating the inlet pipe outside the room or building. When the intake air filter is located outside the building, and particularly on a roof, ambient considerations are important, but may be less important than accessibility for maintenance in inclement or winter conditions.

How to Select an Intake Air Filter
A compressor intake air filter should be installed in, or have air brought to it from a clean, cool location. The compressor manufacturer normally supplies, or recom-mends, a specific grade of intake filter designed to protect the compressor. The better the filtration at the compressor inlet, the lower the maintenance at the compressor. However, the pressure drop across the intake air filter should be kept to a minimum (by size and by maintenance) to prevent a throttling effect and a reduction in compressor capacity. A pressure differential gauge is one of the best tools to monitor the condition of the inlet filter. The pressure drop across a new inlet filter should not exceed 3 pounds per square inch (psi).

Inlet Filter Replacement
As a compressor intake air filter becomes dirty, the pressure drop across it increases, reducing the pressure at the air end inlet and increasing the compression ratios. The cost of this loss of air can be much greater than the cost of a replacement inlet fi lter, even over a short period of time. For a 200 horsepower (hp) compressor operating two shifts, 5 days a week (4,160 hours per year) with a $0.05/kilowatt hour (kWh)
electricity rate, a dirty intake filter can decrease compressor efficiency by 1%–3%, which can translate into higher compressed air energy costs of between $327 and $980 per year.

Source: http://www1.eere.energy.gov/industry/bestpractices/pdfs/compressed_air14.pdf

Determining the Right Air Quality for Your Compressed Air System

2011-03-21T16:50:00.002+07:00

Knowing the proper air quality level required for successful production is an important factor in containing compressed air energy and other operating costs, because higher quality air is more expensive to produce. Higher quality air requires additional air treatment equipment, which increases capital costs as well as energy consumption and maintenance needs. The quality of air produced should be guided by the degree of dryness and filtration needed and by the minimum acceptable contaminant level to the end uses.

Level of Air Quality: Plant Air
Applications: Air tools, general plant air

Level of Air Quality: Instrument Air
Applications: Laboratories, paint spraying, powder coating, climate control

Level of Air Quality: Process Air
Applications: Food and pharmaceutical process air, electronics

Level of Air Quality: Breathing Air
Applications: Hospital air systems, diving tank refill stations, respirators for cleaning and/or grit blasting

Compressed Air Contaminants
Compressed air contaminants can be in the form of solids, liquids, or vapors. Contaminants can enter a compressed air system at the compressor intake, or can be introduced into the air stream by the system itself.

Air quality class is determined by the maximum particle size, pressure dewpoint, and maximum oil content allowed. For more information, see ISO 8573-1 Compressed Air Quality Classes in the Compressed Air System Best Practices Manual. (See references in sidebar).

One of the main factors in determining air quality is whether lubricant-free air is required. Lubricant-free air can be produced either by using lubricant-free compressors, or with lubricant-injected compressors and additional air treatment equipment. The following factors can help one decide whether lubricant-free or lubricant-injected air is appropriate:

If only one end use requires lubricant-free air, only the air supply to it should be treated to obtain the necessary air quality. Alternatively, it may be supplied by its own lubricant-free compressor. If the end uses in a plant require different levels of air quality, it may be advisable to divide the plant into different sections so that air treatment equipment that produces higher quality air is dedicated to the end uses that require the higher level of compressed air purification.
Lubricant-free rotary screw and reciprocating compressors usually have higher initial costs, lower efficiency, and higher maintenance costs than lubricant-injected compressors. However, the additional separation, filtration, and drying equipment required by lubricant-injected compressors will generally cause some reduction in system efficiency, particularly if the system is not properly maintained.

Careful consideration should be given to the specifi c end use for the lubricant-free air, including the risks and costs associated with product contamination before selecting a lubricant-free or lubricant-injected compressor. Centrifugal compressors also offer an alternative for plants whose end uses require lubricant-free air.

Source: http://www1.eere.energy.gov/industry/bestpractices/pdfs/compressed_air5.pdf

Determine the Cost of Compressed Air for Your Plant

2011-03-18T16:26:00.005+07:00

Most industrial facilities need some form of compressed air, whether for running a simple air tool or for more complicated tasks such as the operation of pneumatic controls. A recent survey by the U.S. Department of Energy showed that for a typical industrial facility, approximately 10% of the electricity consumed is for generating compressed air. For some facilities, compressed air generation may account for 30% or more of the electricity consumed. Compressed air is an on-site generated utility. Very often, the cost of generation is not known; however, some companies use a value of 18-30 cents per 1,000 cubic feet of air.

Compressed air is one of the most expensive sources of energy in a plant. The over-all efficiency of a typical compressed air system can be as low as 10%-15%. For example, to operate a 1-horsepower (hp) air motor at 100 pounds per square inchgauge (psig), approximately 7-8 hp of electrical power is supplied to the air compressor. To calculate the cost of compressed air in your facility, use the formula shown below:

Where:
bhp: Motor full-load horsepower (frequently higher than the motor nameplate horsepower—check equipment specification)
0.746: conversion between hp and kW
Percent time: percentage of time running at this operating level
Percent full-load bhp: bhp as percentage of full-load bhp at this operating level
Motor efficiency: motor efficiency at this operating level

Example
A typical manufacturing facility has a 200-hp compressor (which requires 215 bhp) that operates for 6800 hours annually. It is fully loaded 85% of the time (motor efficiency = .95) and unloaded the rest of the time (25% full-load bhp and motor efficiency = .90). The aggregate electric rate is $0.05/kWh.

Cost when fully loaded =

Cost when fully unloaded =

Annual energy cost = $48,792 + $2,272 = $51,064

Typical Lifetime Compressed Air Costs in Perspective—Costs Over 10 Years
Assumptions in this example include a 75-hp compressor operated two shifts a day, 5 days a week at an aggregate electric rate of $0.05/kWh over 10 years of equipment life.

Source: http://www1.eere.energy.gov/industry/bestpractices/pdfs/compressed_air1.pdf

Compressed Air System Control Strategies

2011-03-16T16:17:00.008+07:00

Improving and maintaining compressed air system performance requires not only addressing individual components, but also analyzing both the supply and demand sides of the system and how they interact, especially during periods of peak demand. This practice is often referred to as taking a systems approach because the focus is shifted away from components to total system performance.

Matching Supply with Demand
With compressed air systems, system dynamics (changes in demand over time) are especially important. Using controls, storage, and demand management to effectively design a system that meets peak requirements but also operates efficiently at part-load is key to a high performance compressed air system. In many systems, compressor controls are not coordinated to meet the demand requirements, which can result in compressors operating in conflict with each other, short-cycling, or blowing off—all signs of inefficient system operation.

Individual Compressor Controls
Over the years, compressor manufacturers have developed a number of different types of control strategies. Controls such as start/stop and load/unload respond to reductions in air demand by turning the compressor off or unloading it so that it does not deliver air for periods of time. Modulating inlet and multi-step controls allow the compressor to operate at part-load and deliver a reduced amount of air during periods of reduced demand. Variable speed controls reduce the speed of the compressor in low demand periods. Compressors running at part-load are generally less efficient than when they are run at full-load.

Multiple Compressor Controls
Systems with multiple compressors should use more sophisticated controls to orchestrate compressor operation and air delivery to the system. Network controls use the on-board compressor controls’ microprocessors linked together to form a chain of communication that makes decisions to stop/start, load/unload, modulate, and vary displacement and speed. Usually, one compressor assumes the lead role with the others being subordinate to the commands from this compressor. System master controls coordinate all of the functions necessary to optimize compressed air as a utility. System master controls have many functional capabilities, including the ability to monitor and control all components in the system, as well as trending data, to enhance maintenance functions and minimize costs of operation. Most multiple compressor controls operate the appropriate number of compressors at full-load and have one compressor trimming (running at part-load) to match supply with demand.

Pressure/Flow Controllers
Pressure/Flow Controllers (P/FC) are system pressure controls that can be used in conjunction with the individual and multiple compressor controls described above. A P/FC does not directly control a compressor and is generally not part of a compressor package. A P/FC is a device that serves to separate the supply side of a compressor system from the demand side, and requires the use of storage. Controlled storage can be used to address intermittent loads, which can affect system pressure and reliability. The goal is to deliver compressed air at the lowest stable pressure to the main plant distribution system and to support transient events as much as possible with stored compressed air. In general, a highly variable demand load will require a more sophisticated control strategy to maintain stable system pressure than a consistent, steady demand load.

Source: http://www1.eere.energy.gov/industry/bestpractices/pdfs/compressed_air7.pdf

Compressed Air Storage Strategies

2011-03-14T16:02:00.002+07:00

Compressed air storage can allow a compressed air system to meet its peak demand needs and help control system pressure without starting additional compressors. The appropriate type and quantity of air storage depends on air demand patterns, air quantity and quality required, and the compressor and type of controls being used. An optimal air storage strategy will enable a compressed air system to provide enough air to satisfy temporary air demand events while minimizing compressor use and pressure.

The use of air receivers is especially effective for systems with shifting air demand patterns. When air demand patterns are variable, a large air receiver can provide enough stored air so that a system can be served by a small compressor and can allow the capacity control system to operate more effectively. For systems having a compressor operating in modulation to support intermittent demand events, storage may allow such a compressor to be turned off. By preventing pressure decay due to demand events, storage can protect critical end-use applications and prevent addi-tional units from coming online.

Air entering a storage receiver needs to be at a higher pressure level than the system pressure. A good air storage strategy will allow the differential between these two pressure levels to be sustained. To accomplish such a pressure differential, two types of devices can be employed: Pressure/Flow Controllers (P/FC) and metering valves.

A P/FC is a device that serves to separate the supply side of a compressed air system from the demand side. In a system that employs P/FCs, the compressors generally operate at or near design discharge pressure to ensure that the P/FC receives air at a higher pressure level than it will discharge into the system. This allows the pressure in the demand side to be reduced to a stable level that minimizes actual compressed air consumption. P/FCs are added after the primary receiver to maintain a reduced and relatively constant system pressure at points of use, while allowing the compressor controls to function in the most efficient control mode and discharge pressure range. Properly applied, a P/FC can yield significant energy savings in a system with a variable demand load. See Figure 1.

For situations in which just one or a few applications have intermittent air demand, a correctly-sized storage receiver close to the point of the intermittent demand with a check valve and a metering valve can be an effective and lower cost alternative. For this type of storage strategy, a check valve and a tapered plug or needle valve are installed upstream of the receiver. The check valve will maintain receiver pressure at the maximum system pressure; the plug or needle valve will meter the flow of compressed air to “slow fill” the receiver during the interval between demand events. This will have the effect of reducing the large intermittent requirement into a much smaller average demand. See Figure 2.

Source: http://www1.eere.energy.gov/industry/bestpractices/pdfs/compressed_air9.pdf

Alternative Strategies for Low-Pressure End Uses

2011-03-13T15:36:00.001+07:00

Compressed air is expensive to produce. Because compressed air is also clean, readily available, and simple to use, it is often chosen for applications in which other methods or sources of air are more economical. To reduce compressed air energy costs, alternative methods of supplying low-pressure end uses should be considered before using compressed air in such applications. Many alternative methods of supplying low-pressure end uses can allow a plant to achieve its production requirements effectively.

Before deciding to replace a low-pressure end use with an alternative source, it is important to determine the minimum practical pressure level required for the application.

Alternative Applications to Low-Pressure End Uses

Existing Low-Pressure End Use: Open blowing, mixing
Potential Alternatives: Fans, blower, mixers, nozzles
Reasoning: Open-blowing applications waste compressed air. For existing open-blowing applications, high efficiency nozzles could be applied, or if high-pressure air isn’t needed, consider a blower or a fan. Mechanical methods of mixing typically use less energy than compressed air.

Existing Low-Pressure End Use: Personnel cooling
Potential Alternatives: Fans, air conditioning
Reasoning: Using compressed air for personnel cooling is not only expen-sive, but can also be hazardous. Additional fans or an HVAC upgrade should be considered instead.

Existing Low-Pressure End Use: Parts cleaning
Potential Alternatives: Brushes, blowers, vacuum pumps
Reasoning: Low-pressure blowers, electric fans, brooms, and high-efficiency nozzles are more efficient for parts cleaning than using compressed air to accomplish such tasks.

Existing Low-Pressure End Use: Air motors and air pumps
Potential Alternatives: Electric motors, mechanical pumps
Reasoning: The tasks performed by air motors can usually be done more efficiently by an electric motor except in hazardous environ-ments. Similarly, mechanical pumps are more efficient than air-operated double diaphragm pumps. However, in an explosive atmosphere and/or the pumping of abrasive slurries, the application of a double diaphragm pump with appropriate pressure regulating and air shut-off controls may be appropriate.

Case Study: Low-Pressure End Uses are Replaced with Alternative Applications

A bottling plant was using compressed air in some applications that could be better supported with less energy-intensive methods. The plant was cooling and hardening bottlenecks by blowing cool, compressed air on them. Also, some of the blow mold machines were continuously blowing compressed air through air jets onto the pre-form feed lines to prevent them from jamming. Lastly, the plant’s stackers in the packaging area were using compressed air-operated venturi vacuum producers to pick up and position dividers between layers of bottles. To cool the bottlenecks, the application of a small blower that would blow cool air from chilled water was recommended. The installation of an electromechanical vibrator was identified as the best way to prevent the feed lines from jamming. Finally, a central vacuum system having energy costs that were 30% lower than that of the venturi devices was shown to be as effective as the existing system. The annual compressed air energy savings from implementing these simple modifications was $80,000.

Source: http://www1.eere.energy.gov/industry/bestpractices/pdfs/compressed_air11.pdf

How An Air Compressor Works

2011-03-05T13:41:00.000+07:00

There are many things that you might want to know about how an air compressor works.

You will be able to find many interesting pieces of information out about the air compressors, and you should be able to know how they work. This is a very important factor in the overall impression of the air compressors.

First of all, the air compressors are going to harness the wind at an amazing rate. This is something that many people have wanted to do because air is something that is very useful. The wind can show us that. There is nothing like being able to sit down on a windy day and know that you are going to be able to get the most out of your air compressors. However, you have to understand how they work, first of all.

There are many different types of air compressors. Some are used in building and creating, and some are used in order to convert air to things that we can use, like breathable gas. Most of the time they work in the same way.

They work through using a chamber. The chamber is pressurized, and this pressure is what leads to the harnessing of the air. The air is harnessed through the pressure. This is often hard to comprehend. However, if you think about the way that it works, it is very simple. The air is pulled in through an opening which it cannot exit from. The air enters a chamber and more and more air is pulled in. it is not simply allowed to fill, but more air is pulled in than there is room for. The air compressor continues to pull in more and more air so that it is very tight. Then, the air is compressed even further. After this process is done, the air compressor is full.

Because the way that the chambers inside of the machine work, and because of the very small nozzles, the air is forced out with great speed when it is finally released. This means that the air compressors can be hooked up to anything and then the air can be used. The air compressors themselves simply gather the air into them and then press the air very tightly. The machines are able to do this through pressure. Once the air has been held tightly, it can be released and can be very powerful. It is the release of this air that is what causes it to be used. The air is pushed out of the nozzles at a great speed. However it is pushed out at a very controlled speed. You have complete control over the air.

You can use the air compressors for many things. One of the things that it is used for is to hook up to a nail gun. This helps to drive the nails into the wall at a much faster and stronger pace than a hammer. You can build something much faster this way and it is going to be much easier for you to use. This is a very popular use for the air compressor because it is going to allow you to be sure that you have made the most out of the air. It can also be used in things like power washing. Here, it is hooked up to spray washers or other items and when the air is released, the washers will do their job much better. This way, the air works to propel the water and it can get done much faster. There are also air compressors that aide people. For instance, one of the most popular types of air compressors is the kind that converts the gasses into breathable air so that a person can go diving and still be able to breathe. This is a very popular type of air compressors and it works in the same way. These are very different from the main types of air compressors though. With these, the air is not released in the same way, and it is not sent out in such a hurry. With the other types of air compressors, it is.

Yet you have to be very careful with the air compressors. You should be sure to only use the air compressor for what it is intended. Doing something else with the air compressor, no matter how it benefits you and what you want to accomplish, is going to be bad for the air compressor. You want to be sure that you are able to use this for years and years, so be absolutely sure that you are only using it for what it is meant to be used.

Published At: Isnare.com Free Articles Directory - http://www.isnare.com/

Compressed Air Leaking? Is It The Valve Or Is It The Cylinder?

2011-02-23T00:19:00.000+07:00

"Reducing air leaks in your plant can save thousands of dollars annually. "

Compressed air is one of the most costly forms of energy you can use in your plant, of course, it's one of the most versatile, fast and strong too.

When it's "quiet time" in the plant, wander around the machinery and listen. You will often hear the gentle (or perhaps not so gentle) hissing of air escaping from the exhaust port of your air valves.

The sound of compressed air "chewing up your dollars" as it wafts to atmosphere can be muted if your air valves have mufflers in the exhaust ports, but nevertheless, it can be heard.

Also, there are commercially available ultra-sonic compressed air leak detectors on the market. If your plant doesn't have a "quiet time", which would enable you to actually hear the leaks yourself, investing in an ultrasonic leak detector can bring substantial payback in energy savings.

Usually you'll have one air valve connected to one air cylinder. Usually that cylinder will be double acting - which means that it will have two air lines running to it, and as the air valve shifts back and forth, air will alternatively flow to the cylinder through one line or the other. When it's flowing into one line to the cylinder, the other line is allowing the air at the other end of the cylinder to flow through the valve to exhaust.

While an air valve and cylinder are doing work of course there will be air being exhausted continuously from the air valve exhaust ports.

It's when the machine is down, when it's doing no useful - and hopefully money generating work for you - that air should not be escaping through the valve exhaust ports. At this point that loss of compressed air is just that; loss - of profits - of money.

Inside, the two ends of the cylinder are separated by a piston. The piston is what drives the rod out and back as the cylinder cycles.

Around that piston will be an air seal that "crunches" between the side of the piston and the inside of the cylinder barrel, effectively stopping air from flowing by (bypassing) the piston.

In time that seal will wear, and air will start bypassing into the other side. This means that this air now has an open path from the supply side down the other air line to the valve, and thence to the exhaust port. And a gentle (or not so gentle) hiss occurs as your compressed air dollars exhaust to atmosphere.

Or....inside your air valve there is, too, a series of seals that normally prevent air from getting from the air supply side into the exhaust side of the valve, and then out the exhaust port. And that air, as it gently (or not so....etc. ) is pouring your compressed air dollars from the plant air supply.

So, which is it that's leaking; the seal around the piston in the cylinder, or the seal inside the valve that stops the incoming air from getting across to the exhaust port without going up to the cylinder?

Have a look at the cylinder. If the rod is out, air will be entering the air port at the rear of the cylinder. If the cylinder is in - retracted, the air will be coming into the cylinder at the rod end.

Take the air line that is charged, that is, the air line that is supplying air to the cylinder, and crimp it. Many air lines are made of polyethylene or polypropylene, and it's quite easy to make a bit of a bend in the air line, effectively shutting off air to the cylinder.

Listen at the valve. If the air has stopped escaping the valve's exhaust port, then it's the seal in the cylinder that's at fault.

If, after ensuring that the air to the cylinder is completely stopped, air continues to exhaust from the exhaust port of the valve, then it's the seal inside the air valve that's at fault.

Regardless of which is the culprit, the air valve or the cylinder, get it fixed....fast! Compressed air costs a bundle. You don't want to waste it.

Published At: Isnare.com Free Articles Directory - http://www.isnare.com/

Minimize Compressed Air Leaks

2011-02-02T00:30:00.001+07:00

Leaks are a significant source of wasted energy in a compressed air system, often wasting as much as 20%-30% of the compressor’s output. Compressed air leaks can also contribute to problems with system operations, including:

Fluctuating system pressure, which can cause air tools and other air-operated equipment to function less efficiently, possibly affecting production
Excess compressor capacity, resulting in higher than necessary costs
Decreased service life and increased maintenance of supply equipment (includ-ing the compressor package) due to unnecessary cycling and increased run time.

Although leaks can occur in any part of the system, the most common problem areas are couplings, hoses, tubes, fittings, pipe joints, quick disconnects, FRLs (filter, regulator, and lubricator), condensate traps, valves, flanges, packings, thread seal-ants, and point-of-use devices. Leakage rates are a function of the supply pressure in an uncontrolled system and increase with higher system pressures. Leakage rates identified in cubic feet per minute (cfm) are also proportional to the square of the orifice diameter.

Leak Detection
The best way to detect leaks is to use an ultrasonic acoustic detector, which can recognize high frequency hissing sounds associated with air leaks. These portable units are very easy to use. Costs and sensitivities vary, so test before you buy. A simpler method is to apply soapy water with a paintbrush to suspect areas. Although reliable, this method can be time consuming and messy.

Example
A chemical plant undertook a leak-prevention program following a compressed air audit at their facility. Leaks, approximately equivalent to different orifice sizes, werefound as follows: 100 leaks of 1/32” at 90 pounds per square inch gauge (psig), 50 leaks of 1/16” at 90 psig, and 10 leaks of 1/4” at 100 psig. Calculate the annual cost savings if these leaks were eliminated. Assume 7,000 annual operating hours, an aggregate electric rate of $0.05 kilowatt-hour (kWh), and compressed air generation requirement of approximately 18 kilowatts (kW)/100 cfm.

Cost savings = # of leaks x leakage rate (cfm) x kW/cfm x # of hours x $/kWh

Using values of the leakage rates from the above table and assuming sharp-edged orifices:

Cost savings from 1/32” leaks = 100 x 1.46 x 0.61 x 0.18 x 7,000 x 0.05 = $5,611
Cost savings from 1/16” leaks = 50 x 5.72 x 0.61 x 0.18 x 7,000 x 0.05 = $10,991
Cost savings from 1/4” leaks = 10 x 100.9 x 0.61 x 0.18 x 7,000 x 0.05 = $38,776
Total cost savings from eliminating these leaks = $57,069

Note that the savings from the elimination of just 10 leaks of 1/4” account for almost 70% of the overall savings. As leaks are identified, it is important to prioritize them and fix the largest ones first.

Suggested Actions

Fixing leaks once is not enough. Incorporate a leak prevention program into operations at your facility. It should include identi-fication and tagging, tracking, repair, verification, and employee involvement. Set a reasonable target for cost-effective leak reduction—5%-10% of total system flow is typical for industrial facilities.
Once leaks are repaired, reevaluate your compressed air system supply. Work with a compressed air systems specialist to adjust compressor controls. To maximize energy savings, compressor run time must be reduced to match the reduced demand.

Source: http://www1.eere.energy.gov/industry/bestpractices/pdfs/compressed_air3.pdf

11 Tips for Air Compressor Maintenance

2011-01-02T20:35:00.000+07:00

Now that you've invested in an air compressor to run all of your air tools you're going to have to learn how to keep it up and running. Because the standard handyman's air compressors don't typically require daily upkeep, it's easy to forget about them and neglect their upkeep. This can be a costly oversight so it's vital for you to keep an eye on the following maintenance tips.

Maintenance Tip 1: Read and Follow Your Air Compressor's Manual

Nothing stops an air compressor faster than an owner who doesn't read the owner's manual.

There's going to be some simple tips in there for you that will help you to get a nice long life out of your air compressor - simple stuff for you to do that you would never have thought to do unless you read it. Plus, if you don't follow the rules in your air compressor manual there's a chance that you'll void your warranty. That in itself should be enough of an incentive to read the "flipping" manual.

Maintenance Tip 2: Drain The Moisture From The Tanks

The receiver tank collects moisture from the air that it's compressing - especially if you live in a humid climate. Most tanks have a valve for draining this moisture that accumulates and it's up to you to make sure that these are drained regularly. Before draining the water you should be sure to release the air pressure from the tanks.

Maintenance Tip 3: Clean Intake Vents

If you force your air compressor to work too hard to intake air you're losing power on your compression. This will gradually degrade the quality of your tool. Be sure to keep your intake vent as clean as possible and check them regularly especially if you're working in a dusty or dirty environment.

Maintenance Tip 4: Tighten All Fasteners

Your air compressor's a running, vibrating engine and it will loosen its screws, nuts and bolts on a regular basis. Be sure to check these periodically and tighten them up if you find any that have jiggled loose.

Maintenance Tip 5: Check Hoses Regularly

Check all your hoses periodically as they are the veins of your air compressor. If they become cracked or corroded they could soon begin to leak and then put undue strain on the rest of your compressor's components. Be sure to check them and replace them if you find them cracked or damaged.

Maintenance Tip 6: Test the Safety Shutdown System

Your air compressor may have a built in safety shut down. The function of this system is to shut off your compressor if it's getting too hot, or if the engine's oil pressure is too low. This test will help you ensure a longer lasting compressor.

Maintenance Tip 7: Check and Change Air Filters As Needed

A filthy air filter is only hurting your air compressor by allowing dirty air from the outside in, plus forcing it to work harder to intake air. Check your filters regularly and change them if you notice a heavy build up of dust and dirt. Change every six months or so if you use it infrequently.

Maintenance Tip 8: Clean the Fuel Tank

As with any engine you need to periodically clean out the fuel tank to ensure optimal operating conditions. You should look to clean out the engine on your air compressor once every year or so to remove any residual build up from the fuel. This will preserve the life of your engine.

Maintenance Tip 9: Check and Change the Compressor Oil

If you're running a compressor that uses oil you should be checking it on a daily basis to make sure that your machine is topped off. Then, every 500-1000 hours of use you should be changing this oil to ensure maximum functioning of your air compressor.

Maintenance Tip 10: Change the Separator Element

The separator element prevents the excessive use of oil, but it has to be replace periodically. Keep your compressor in top condition by replacing the separator element every 1,000 hours of operation.

Maintenance Tip 11: Clean the Heat Exchangers

If your heat exchangers are dirty then they can't do their job, which is to reduce the operating temperatures of your air compressor. Clean them regularly to keep your operating temperatures down and increase the life span of your air compressor.

By following the tips above you'll ensure a nice long life for your air compressor, plus the jobs that you use it for will go faster and more productively. A well maintained air compressor is a wonderful machine for any job site or workshop, so keep yours running smoothly.

Charlie Slagle and his ToolCrib team deliver discount power tool prices at ToolCrib.com! Visit http://www.ToolCrib.com for great prices on great power tools today!

Article Source: http://EzineArticles.com/?expert=Charlie_Slagle

Factors Governing the Selection of Compressed Air Filters

2010-12-19T20:08:00.000+07:00

Compressed air filters are designed to remove air borne particles from a moving, pressurized air stream.

Compressed air purification equipment is essential to all modern production facilities; at its best, the equipment should provide the optimum balance between air quality and low operating cost. There are numerous manufacturers offering products for the filtration and purification of air; compressed air filter costs cover a wide range - but initial purchase cost cannot always indicate the effectiveness of a piece of equipment. In assessing the suitability of the product, the purchaser will want to assess:

delivered air quality required by their application
environmental impact of use
overall cost of operation over the life of the equipment

One way to make these assessments is to compare the performance standards of the different manufacturers' products according to the standards that apply via ISO (the International Standards Organisation) under which there are a series of standards covering Compressed Air Quality. There are nine areas of quality classification for the main air contaminants as well as testing methods for them. The air purity classifications dictate how much contamination is allowable per cubic metre of compressed air. These classifications are used by manufacturers to rate the air delivered by their products. In this way, users can easily compare and contrast the performance of different products. The caveat to this is that the test methods were originally developed to verify air quality in the system rather than testing the purification equipment which means that not all products are tested in the same way.

The selection of the correct air filter for compressed air depends on specific parameters of use and location. Compressed air quality regulations are governed by the widespread and growing demands of industry. In manufacturing technology (for example, in food and beverage production, hospitals, electronics manufacturing or pharmaceuticals), quality of compressed air is relative to use and differs widely. Air filters therefore need to be selected for the properties that best match the air quality needed to prevent downtime, systems breakdown or low productivity. Where air impurities such as viruses, bacteria or possibly dust from insecticides present great danger, the selection of filter and filter material is of huge importance. The exact grade of air quality required differs therefore, according to the factors at play.

Delivering dry, contaminant-free air allows more efficient, effective and economical operations. Damage occurs to plant and equipment when water, oil, gases and dust enter into systems such as pipelines and fittings; compressed air filters and dryers can help eliminate the conditions for such damage/malfunction.

It is generally held that there are 10 major contaminants found in compressed air. Nine of these are removed using filtration technology. Filter design is based mostly on what works! In other words, development is largely empirical - the result of experiment and observation. Filter material design and specification needs to demonstrate better than adequate retention capacity, separating ability, a stable pressure build up and low pressure loss.

The type of material and its weight, the thickness of layer, loss of pressure at nominal volume flow, volume flow per unit of surface and permissible static pressure difference are all considered in the specification of filter material. However, due to the wide range of locations and conditions in which compressed air is used, these are only foundational specifications; there are other elements that need to be accounted for such as chemical and thermal resistance for example.

In conclusion, compressed air filters have a wide range of applications and selection of the most suitable will depend not only on cost (possibly this is the least important factor) but on the contaminants to be removed, the operating environment, the air quality delivered, environmental impact, and the overall cost of operation over the lifetime of the product.

Caron Rose writes for HP Pneumatics, an Aberdeen company of pneumatic engineering experts. HPP supply and fit pneumatic tools for industry, as well as repairing, servicing and installing pneumatic and compressor systems. The service offered to customers is of the highest priority - and is based on experience, competitive prices, extensive stock holding and speedy delivery.

For more information about our pneumatic air tools, services or products, call us for an informal chat on +44 (0) 1224 783371.

Article Source: http://EzineArticles.com/?expert=Caron_J_Rose

How to Make Your Industrial Air Compressor Operate More Efficiently

2010-12-12T22:03:00.000+07:00

It's no secret in the industrial world that compressed air is the least efficient form of energy used on a shop floor. Dollar for dollar, the cost of producing pneumatic energy for various machinery functions is staggering.

Unfortunately, a rotary screw air compressor is very inefficient by design. Electricity enters the factory from the utility pole and does not produce energy until it has turned the rotary screw compressor, pressurized the air lines, proceed through the shop to its intended destination, and then finally producing movement or action via a pneumatic cylinder or device. This complex and elaborate system has many opportunities for waste. The key to conserving energy and producing the most useful pneumatic energy for the least amount of money is analysis and observation. Many inefficiencies can be corrected once they have been identified.

An air compressor is not just a machine. Since the air compressor produces energy it should be treated as a system, hence the compressor becomes the compressed air system.

Begin by listing the air uses and their design cfm and pressure. Record the power consumption before making any system changes. this can be accomplished through the use of a kwh meter. Identify and track and leaks, most of these should be easy to find since they are most often near the point of end use. Once the leaks have been identified, begin repairs, of course from the largest air leaks on down the line. The installation of a flow meter on the main line is also helpful to gain an understanding of the savings from a standpoint of cfm. The compressed air system should also be operated at the lowest possible pressure once some of the larger leaks have been repaired. Another tip is to install a normally closed air valve on the main line to each piece of equipment so the entire machine can be taken out of the compressed air circuit when not in use. Factory engineers should also take a step back and analyze whether compressed air is the best application for your automation in the first place. Many point of use pneumatic operations operate inefficiently by design. Installation of additional gauges and flow motors throughout your shop can also supply a better understanding of factory use and misuse.

The compressed air system is a complex system that warrants constant monitoring. Saving money on utilities is a priority for any factory or industrial facility and an unruly air compressor can be the source of much waste. Remember to baseline and track your progress as you make changes and improvements. This progress needs to be documented for the decision makers within your organization.

Chet is affiliated with Industrial Flea Market who offers a free forum to list used industrial parts and machinery for sale.

Article Source: http://EzineArticles.com/?expert=Chet_Val

Variable Speed Compressors

2010-12-04T10:35:00.001+07:00

Variable Speed Compressors are also know as variable speed drive compressors, and are air compressors that take advantage of variable speed drive technology. They employ a special drive which controls the RPM (Revolutions Per Minute) speed of the compressor, and this in turn saves energy when compared to its fixed speed equivalent.

The most common form used in the air compressor industry uses a variable-frequency drive, and this is used to convert the AC input power to DC and then back to a quasi-sinusoidal AC power, with the use of an inverter switching circuit.

The main benefits are, reduced power cost, reduced power surges, and the delivery of more constant pressure. The downside is the heavy expense of the drive and their sensitivity to heat and moisture.

They combine a speed inverter, which converts the AC signal to DC and speeds up or slows down the motor, with a pressure transducer to precisely match the compressed air output to demand. The energy efficiency of these compressors results in worthwhile savings on energy costs for users with fluctuating compressed air requirements. The demands for air in nearly every compressed air system fluctuate to some extent. If a compressor has a fixed speed, then it means that it will be switching on and off and probably running inefficiently.

As energy costs have increased it has become more cost effective to use these compressors. These types of compressors will only produce the volume of compressed air required and can be a very effective way of saving energy. If more than one fixed compressor is used, it may be more cost effective to have only one compressor to handle the variable part of the air demand. Studies have proven that better control, housekeeping and maintenance could save operators up to one third of the energy used across their compressed air systems.

There are other types of air compressors and these can include:

Rotary screw compressors
Variable speed compressors
Vane compressors
Reciprocating compressors

With the focus on reducing your carbon footprint, variable speed technology can reduce electrical running costs whilst maintaining system reliability.

If you are in need of this service check out our product pages, they contain many companies that specialise in this. John Cheesman writes about Variable Speed Compressors. Visit the Businessmagnet product page for details and suppliers of Variable Speed Compressors.

Article Source: http://EzineArticles.com/?expert=John_Cheesman

Top 7 Compressed Air Energy Saving Tips

2010-11-26T18:16:00.000+07:00

Would you like to reduce electrical costs related to your compressed air system?

More than likely - you can. Start by determining your annual compressed air electrical costs by using this formula:

Brake Horse Power X 0.746 X Annual Hours of Operation X KWH (Kilowatt-Hour) Cost (divided by) Motor Efficiency

NOTE: 1 CFM (Cubit Feet per Minute) @ 100 PSIG (pound-force per square inch gauge) FOR 8760 HOURS COST $110.00 PER YEAR IN ELECTRICAL COST

Next...follow these Top 7 Compressed Air Energy Saving Tips:

1. Fix your Air Leaks

If you do nothing else - follow this one tip: Find and fix your compressed air leaks. Air leaks are industrys' "biggest looser"!

The average plant loses 20% to 30% it its compressed air through multiple small air leaks. The money spent on man power and parts to find and fix these leaks is well worth it. Note (a 1/4 inch hole will flow 103 cfm @ 100 psig)

2. Change to Synthetic Lubricants

If you are using petroleum based lubricants, you could experience up to an 8% energy savings by switching to Compressor Synthetic Lubricants. Plus extend equipment life and save on oil changes and disposal cost.

3. Reduce Plant Operating Pressure

If possible - reduce overall plant pressure. Less pressure > Less CFM used > less energy consumed.

TIP: Reduce plant pressure 2 pounds at a time, then test run for minimum 24 hours. If any equipment has issues...then increase pressure 2 pounds until running smoothly again. For every 2 pound pressure reduction -you save 1% of the electrical cost to run the air compressor.

4. Check Differential Pressure on Air Compressor Filters.

Start at the compressor cabinet filter then check the compressor inlet filter.

Note: A dirty inlet filter can cost you 1% to 3 % in additional electrical costs. Why? Because decreased air flow to the compressor inlet valve increases the compression ratios resulting in more run time.

Next check the air/oil separator differential pressure under a full load. A new separator causes a differential pressure drop of approximately 2-3 psig. When your pressure drop reaches 8-10 psig, then it is time to change your separator elements. A dirty separator element can cost you up to 5% in additional electrical cost.

Next change the control air filter element. This often over looked, but still important filter where the controls receive their air signal. A pressure drop here causes the controls to receive the lower pressure signal loading the compressor more and using more electricity.

5. Reduce the Compressor Inlet Temperature

By reducing inlet air temperature 10°F below 70°F, you save 2% on electrical usage. Your benefit increases up to 8% on a 30°F degree day. But increasing the inlet temperature 10°F above 70°F will cost you 2% in additional electrical usage for every 10°F up to 10% at 120°F. (Inlet temperature has very little affect on Lubricated screw compressors)

6. Check Differential Pressure on Compressed Air Line Filters.

Size Compressed Air Filters to be twice (2x) your compressor CFM flow rate. This will lower your pressure drop approximately 2-3 psig and save 1% on energy costs. Elements will last twice (2x) as long and you will save on maintenance costs.

7. Know what quality of compressed air your plant needs.

The cleaner & dryer the compressed air the more energy used.

Check with the manufacturer of your equipment to determine the quality of air needed.

Tommy McGuire
McGuire Air Compressors, Inc.
"Real People with Real Air Compressor Experience"
1-888-229-9999
compressors@mcguire.biz
www.industrialaircompressors.biz/

Article Source: http://EzineArticles.com/?expert=Tommy_McGuire

What is Contaminating Your Compressed Air?

2010-11-13T01:18:00.000+07:00

"Clean, dry, oil free compressed air and gas is a basic need for many industries"

One drop of unwanted oil can cause an entire automated process to malfunction. It can cause seals in pneumatic valves and cylinders to swell, resulting in sluggish operation - or in worst cases, complete seizure of moving parts.

Three things that can contaminate your compressed air system and ruin your product or processes.

1) Solid particles come from ambient air contaminants like dust and from rusted, oxidized pipework. They will cause pneumatic equipment to malfunction, cause instrument and control failures, and contaminate end products.

2) Condensed water droplets come from the humidity in ambient air. Water will oxidize pipework and pneumatic equipment, ruin paint finishes and end products.

3) Liquid oil and oil vapors are introduced by compressor lubricants and by hydrocarbon vapors present in ambient air. Oil-free compressed air is particularly important in food and pharmaceutical processes.

Compressed Air Filters effectively and efficiently remove solid particles, remnants of oil, water mist and other liquid from compressed air and gas which can... -wear out pneumatic machinery -block valves and orifices, causing high maintenance -corrode piping systems which cause costly air leaks -result in abrupt equipment stoppages, lost product, time and money

How to clean your Compressed Air...

Depending on the level of air purity required, different levels of filtration and types of filters are used. Filters are used in conjunction with other "filtering equipment" - such as a Water Separator or Compressed Air Dryer- to help remove harmful contaminates from your system.

General Purpose Filters - also called "particulate filters" are used to remove solid particles. Oil and Oil Vapor Removal Filters - also called "coalescing-type filters" are used to remove oil and vapors.

A particulate filter is recommended after a desiccant-type dryer to remove desiccant fines. A coalescing-type filter is recommended before a desiccant type dryer to prevent fouling of the desiccant bed. Additional filtration may also be needed to meet requirements for specific end uses. Compressed air filters downstream of the air compressor are generally required for the removal of contaminants, such as particulates, condensate, and lubricant.

Listed below are types of filtration equipment available in today's market. The specifications offered are from Champion Air Compressors as a market example.

Water Separator Installation: after an air compressors' (or a stand-alone) aftercooler Design: One-stage filtration with two stainless steel orifice tubes. Labyrinth style air flow path removes liquid water by forcing abrupt directional changes. Performance*: Handles bulk liquid inlet loads to 30,000 ppm w/w and provides 10 micron solid particulate separation. Efficient to flows as low as 5% of rated flow.

Separator/Filter Installation: after an air compressors' (or a stand-alone) aftercooler or as a prefilter to a refrigerated dryer Design: Two-stage filtration with first stage of two stainless steel orifice tubes which remove bulk liquids and solid particulates to 10 micron. Second stage has in-depth coalescing fiber media which captures solid particulates to 3 micron. Performance*: Handles bulk liquid inlet loads to 25,000 ppm w/w and provides 3 micron solid particulate filtration.

General Purpose Filter Installation: 1 micron particulate prefilter for refrigerated dryers and high efficiency oil removal filters. Design: Two-stage filtration with a first stage of multiple layers of fiber media which pre-filter the air. Second stage has indepth coalescing fiber media which coalesces oil aerosols and removes finer particulates to 1 micron. Performance*: Handles bulk liquid inlet loads to 2,000 ppm w/w, provides 1 micron solid particulate filtration and oil removal to 1 ppm.

Dry Particulate Filter Installation: Dry, solid particulate afterfilter for heatless desiccant dryers Design: Two-stage filtration with life-prolonging outside/in air flow with first stage of alternate layers of fiber media and a media screen capturing large particulates. Second stage captures finer particulates. Not designed for any liquid loading. Performance*: Provides 1 micron solid particulate filtration of desiccant dust.

High Efficiency Oil Removal Filter Installation: Prefilter to desiccant and membrane dryers, afterfilter to refrigerated dryers and stand-alone oil removal at the point-of-use of compressed air. Design: Two-stage filtration with a first stage of multiple layers of fiber media which prefilter the air. Second stage has in-depth coalescing fiber media which coalesces oil aerosols. Includes an outer-coated, closed cell foam sleeve. Performance*: Handles bulk liquid water inlet loads to 1,000 ppm w/w and provides 0.008 ppm oil aerosol removal and 0.01 micron solid particulate separation.

Maximum Efficiency Oil Removal Filter Installation: Prefilter to desiccant and membrane dryers with a Grade C prefilter, oil-free air applications. Design: Two-stage filtration with a first stage of a coated, closed-cell foam sleeve which acts as a prefilter and flow disperser. Second stage has in-depth coalescing fiber media which coalesces fine oil aerosols. Includes an outer coated, closed cell foam sleeve. Performance*: Handles bulk liquid water inlet loads to 100 ppm w/w and provides 0.0008 ppm oil aerosol removal and 0.01 micron solid particulate separation.

Oil Vapor Removal Filter Installation: Afterfilter to high efficiency liquid oil removal filters for true oil-free applications. Design: Two-stage filtration with a generously-sized first stage of a stabilized bed of carbon particles which remove the majority of the oil vapor. Second stage has multiple layers of fiber media with bonded microfine carbon particles which remove the remaining oil vapors. Includes an outer-coated, closed cell foam sleeve which prevents fiber migration. Performance**: No liquid should be present at filter inlet. Provides 0.003 ppm w/w oil (as a vapor) removal and 0.01 micron solid particulate separation.

* Filter efficiencies have been established in accordance with CAGI standard ADF400 and are based on 100°F (38°C) inlet temperature ** Filter efficiency has been established in accordance with CAGI standard ADF500 and is based on 100°F (38°C) inlet temperature

Filtration only to the level required by each compressed air application will minimize pressure drop and resultant energy consumption. Elements should also be replaced as indicated by pressure differential to minimize pressure drop and energy consumption, and should be checked at least annually. You can customize your air treatment applications by choosing the combination of dryers, filters, and separators that give you the level of clean air or gas that you need.

Who establishes quality industry standards for filters?

ISO 8573.1 was developed in 1992 by ISO (International Organization for Standardization) to help plant engineers specify desired compressed air quality globally by providing "Quality Classes" for solid particulates, humidity and oil. Quality classes provide engineers with an internationally accepted unit of measure.

A typical pharmaceutical plant, for example, would have a compressed air specification of ISO Quality Classes 1.2.1. This is equivalent to 0.1 micron particulate filtration, -40°F (-40°C) dew point, and 0.008 ppm (0.01 mg/m3) oil filtration. No matter what language is spoken and what unit of measure is used, using ISO 8573.1 Air Quality Classes ensures that your factory will get the compressed air quality you specified.

Owned & Operated by
Tommy McGuire
McGuire Air Compressors, Inc.

"Real People with Real Air Compressor Experience"

For Champion Air Compressors...
http://www.industrialaircompressors.biz/

For Reelcraft Hose Reels for Air, Water, Oil & fluid
plus Electric Cord Reels & Welding Cable Reels...
http://www.hosereels.biz/

Email us:
compressors@mcguire.biz

Call us:
1-888-229-9999

Fax us:
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Mailing address:
McGuire Air Compressors,Inc.
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Graham NC 27253

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Controlling The Dangers Of Compressed Air

2009-07-29T16:56:00.002+07:00

There are two concerns in safety when using compressed air. (Flying objects and the air itself) Horseplay has been a cause of some serious workplace accidents caused by individuals not aware of the hazards of compressed air. Some television shows have shown bad examples on the use of compressed air.

Compressed air is extremely forceful. Depending on its pressure, compressed air can dislodge particles. These particles are a danger since they can enter your eyes or possibly the skin. The potential damage would depend on the size, weight, shape, composition, and speed of the particles. There have also been reports of hearing damage caused by the pressure of compressed air and by its sound caused by the nozzle.

Compressed air itself is also a serious hazard. On rare occasions, some of the compressed air can enter the blood stream through a break in the skin or through a body opening. An air bubble in the blood stream is known medically as an embolism, a dangerous medical condition in which a blood vessel is blocked, in this case, by an air bubble. An embolism of an artery can cause coma, paralysis or death. While air embolisms are usually associated with incorrect diving procedures, they are possible with compressed air due to high pressures. The consequences of even a small quantity of air or other gas in the blood can quickly be fatal.

Although many people know using compressed air to clean debris or clothes can be hazardous, it is still used because of old habits and the easy availability of compressed air in many workplaces. Cleaning objects, machinery, bench tops, clothing and other things with compressed air is dangerous. Injuries can be caused by the air jet and by particles made airborne.

When compressed air cleaning is unavoidable, hazards can be reduced. Use the lowest air pressure that is still effective to handle the task. A "quiet" nozzle should be selected. Personal protection equipment must be worn to protect the worker's body, especially the eyes, against particles and dust under pressure. Air guns should also be used with some local exhaust ventilation or facilities to control the generation of airborne particulates. The use of chip guards can deflect flying dust or debris, extension tubes will give the worker a safer working distance, or even air guns equipped with injection exhausts and particle collection bags are other options to consider in compressed air safety.

Source: Brent Bowlin - a health and safety researcher who has helped businesses in implementing safety programs. For help contact him at abbsafetynet@gmail.com and for safety supplies and a safety program manual go to http://www.safetysuppliescanada.com, they deliver anywhere.

Air Compressor Buying Tips

2009-07-05T23:41:00.003+07:00

How important is air to human life? Since you started being aware of the things around you, you probably have considered the importance of air in one’s life and with the day-to-day activities that confront every person. Air does not only benefit all living beings. The use of a compressed air is widely used in several other areas, most particularly in the business arena. Compressed air is basically used as an essential part of a multitude of manufacturing, industrial, commercial, and automotive applications. The operation of an air compressor concerns a large percentage of the total expense cost of a plant’s utility budget.

1. How They Work

Air compressors work out by two different methods. The first is the air compressor that runs by electricity. The other one is the air compressor that runs by means of natural gas. Obviously, it is the air compressor that feeds on natural gas that is more cost effective among the two. An industrial plant will be able to save more and cut down the cost consumption when an air compressor by natural gas is employed. However, if the place for the working operation is located in an enclosed area, then it is health-wise to make use of an air compressor run by electricity in order to get rid of the gas fumes that may be a threat to the health’s safety of all the workers.

2. Suitable For Heavy Workload

If a business plant operates at a high level and needs an air compressor that will serve its purpose for heavy duties, then a two-stage air compressor is advisable. In more ways than one, this heavy-duty air compressor provides a higher level of efficiency compared to that of the smaller, single-stage air compressors. Also, this heavy-duty air compressor is also able to store large amounts of air needed for future use.

3. Types Available

If you are to buy an air compressor, it is best to think of its capacity to store compressed air. It is essential to consider the power delivered by the types of air compressors available in the market. A two-stage air compressor is more energy efficient compared to that of the single-stage compressor. Why? It is so because of the fact that the two-stage air compressor produces more air per unit of horsepower. Likewise, less heat is generated. Thus, paving the way for a longer life service. Take note that electric air compressors can also be utilized for light-duty applications. There are portable electric compressors that are handy to be carried from one location to another as you wish.

4. Excellent Results

Then, an air compressor buyer needs to bear in mind the efficiency rating of his prospect air compressor equipment. Surely enough, you would want every purchase to be not only valuable but capable as well. What will you do to an equipment that will not survive the tough challenge you require of it after every single cent that you have spent for it?

5. Considerations

In considering an air compressor for purchase, the ratings set by the mechanical engineers association can be the bases for the testimonies of the quality and protective features comprised into the equipment. Next, be sure that the air compressor that you are planning to buy includes a safety relieve valve for the escape of air if the tank’s pressure exceeds the maximum, a belt guard for protection purposes, and an enclosed air intake filtration system.

6. Attachments

The air compressors need to be secured with the attachments that are to be used for its connection to the air tube. The common tool attachments employed into the air compressor are the blowgun, a nail gun, air stapler, air sander, spray gun, or air ratchet wrench. It is the blowgun which is used for the compressed air to blow away the dirt and dust. The nail gun takes charge of the nail’s application even without the hammer. These tools are widely available in hardware stores for purchase.

When buying either a brand new or a second-hand air compressor, these things are to be carefully noted. It is for your own benefit both as the buyer and the user. Another tip to take note of is the frequency that an air compressor is to be used. If the air compressor’s use is called for in just a few times, then it is wise to just rent it. The tools as attachments can also be rented. If, however, the use of the air compressor is permanently required, then it will be better to buy one.

Air Compressor Suppliers

2009-06-21T10:29:00.001+07:00

There are many different Air Compressor Suppliers out there, all offering a different range and different manufacturers, some specialize specifically in a certain make whilst others will stock all.

All of the suppliers have their pros and cons:

Bambi: are one of these focusing on quality as their primary component; they use the latest tilting piston technology and try to produce some of the lowest noise compressors. Another benefit they can offer is their Silent Range they are manufactured with acoustic hoods rendering the noise output to almost nothing. Bambi also offer up a Budget Range this is designed specifically for the home, trade and DIY users, they cost a lot less than you would expect but still offer good results, power and low noise levels, some of the compressors have noise levels as low as 40 dBa.

SIP: tend to offer low maintenance units that are fast and convenient for trade and DIY users, their industrial units are belt driven with large pneumatic wheels offering easy maneuverability. SIP also tend to have a slower pump speed offering greater life span and reliability. SIP are aimed toward the Semi Professional user, they are compact, powerful and robust.

Fiac: This manufacturer and supplier have over 25 years experience in the field of compression, their units are always manufactured to the latest European standards. The systems produced are aimed at professional users and tend to lean away from the DIY users.

Apollo: Designed mainly for spraying purpose, they specialize in a range of Spray compressors for DIY ones to Professional ones.

Wesley Clarke writes about Air Compressor Suppliers. Visit the Businessmagnet product page for details and suppliers of Air Compressor Suppliers.

Article Source: http://EzineArticles.com/?expert=Wesley_C_Clarke

Air Compressors

2009-06-09T23:50:00.000+07:00

Air compressors are mechanic devices that take in air and then compress and store it in a compressed form (meaning, it occupies less space than in its normal state). Air compressors are equipped with a tank that holds the compressed air inside. The tank is able to withstand all the pressure that the air applies inside it, but there are always signs that warn the user that damaging the tank can result in an accident.

One major difference between the various types of air compressors is that some of them are oil-lubricated while some others are not. Those that are not oil lubricated are also called oil-free compressors. Oil-free compressors boast the advantage that they don’t need oil in order to operate, while oil-lubricated compressors do. Additionally, oil-lubricated compressors need to have their oil changed after certain periods of operation.

Another difference that can be seen among air compressors is that some of them are stationary (meaning they are static or unmovable), while some others are designed from scratch to be portable. Common air compressors are not used for industrial purposes, and they occupy the same volume as a medium-sized table. This type of compressor usually comes with built-in wheels in order to be more portable. However, air compressors aimed at industrial use can occupy areas larger than one, two, or even more rooms. These compressors are not intended to be moved more than a few times during their lifetime. Moving these compressors requires money as well as good planning.

Air compressors can be found in homes, small businesses, service stations, or in large industries. Their usage ranges from dust cleaning to heavy industry usage (inside machinery) and gas turbines. Air compressors play an essential role in the correct operation of many devices and procedures.

Compressors provides detailed information on Air Compressors, Compressor Parts, Compressors, Gas Compressors and more. Compressors is affiliated with Electric Pressure Washers.

Article Source: http://EzineArticles.com/?expert=Thomas_Morva

About Oil Less Air Compressors

2009-05-23T23:46:00.001+07:00

Portable air compressors vary by size and power level, and there are a few different models available from which to choose depending on the tools you will use. Be sure to check the power requirements of your tools to ensure that you purchase a model that has sufficient power to run your strongest tool. Regardless of the compressor you purchase, it is always very important to follow the safety precautions including safety goggles, protective clothing and proper footwear.

Portable rotary screw compressors are one of the more commonly used compressors. They range from 65 to 1,600 cubic feet per minute, with pressure ratings ranging from 100 to 350 PSI. As discussed above, the compressor you need depends on your tools and the required power level. Contractors often use 185 CFM because they are able to power two tools simultaneously. One benefit to this compressor is its suitability for both the lighter and heavy duty jobs.

The truck mounted compressor is an oil less air compressor and can be mounted in the bed or under the hood of a truck. These compressors are excellent space savers, a great advantage for those with limited space available. Their power source is from the engine of the truck which allows them to be a low-maintenance compressor. However, one disadvantage is that the truck must be running to provide the compressor the power it needs.

Finally, the deck mounted compressor is mounted in the bed of the truck but can be removed and left at the job site. This compressor does not rely on the truck for power since it has its own engine. However, it does require fuel to power the engine, unlike the truck mounted compressor which runs from the truck. The engine also requires regular maintenance.

As you see, the power source of compressors varies with some powered electronically and others requiring fuel. With either type, though, the air is stored in the holding tank and the tools are to be attached with a hose. A valve regulates the pressure which is measured by a gauge.

Quincy and Husky are two of the major brands of compressors. Quincy’s rotary screw compressors are very durable, reliable and quiet with its power level varying from 10 to 350 horsepower. Quincy’s available air compressors range in size from the smaller tank models to the larger, stationary styles.

Husky’s line of small air compressors are generally made for home and personal use. The 1.75 gallon tank compressor has 135 PSI power has an oil free pump for easy maintenance and is easy to transport with its telescope handle. This model of Husky compressors is good for running tools such as nailing guns, for example, and is also useful for insulation purposes. Husky’s four gallon model has 125 PSI power and is a good choice for running small tools, spraying and even inflating tires and other recreational items. The four gallon model is a compressor for homeowners.

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Compressed Air Leaking? Is It The Valve Or Is It The Cylinder?

2009-05-23T09:19:00.000+07:00

Reducing air leaks in your plant can save thousands of dollars annually. Compressed air is one of the most costly forms of energy you can use in your plant, of course, it's one of the most versatile, fast and strong too.

When it's "quiet time" in the plant, wander around the machinery and listen. You will often hear the gentle (or perhaps not so gentle) hissing of air escaping from the exhaust port of your air valves.

The sound of compressed air "chewing up your dollars" as it wafts to atmosphere can be muted if your air valves have mufflers in the exhaust ports, but nevertheless, it can be heard.

Also, there are commercially available ultra-sonic compressed air leak detectors on the market. If your plant doesn't have a "quiet time", which would enable you to actually hear the leaks yourself, investing in an ultrasonic leak detector can bring substantial payback in energy savings.

Usually you'll have one air valve connected to one air cylinder. Usually that cylinder will be double acting - which means that it will have two air lines running to it, and as the air valve shifts back and forth, air will alternatively flow to the cylinder through one line or the other. When it's flowing into one line to the cylinder, the other line is allowing the air at the other end of the cylinder to flow through the valve to exhaust.

While an air valve and cylinder are doing work of course there will be air being exhausted continuously from the air valve exhaust ports.

It's when the machine is down, when it's doing no useful - and hopefully money generating work for you - that air should not be escaping through the valve exhaust ports. At this point that loss of compressed air is just that; loss - of profits - of money.

Inside, the two ends of the cylinder are separated by a piston. The piston is what drives the rod out and back as the cylinder cycles.

Around that piston will be an air seal that "crunches" between the side of the piston and the inside of the cylinder barrel, effectively stopping air from flowing by (bypassing) the piston.

In time that seal will wear, and air will start bypassing into the other side. This means that this air now has an open path from the supply side down the other air line to the valve, and thence to the exhaust port. And a gentle (or not so gentle) hiss occurs as your compressed air dollars exhaust to atmosphere.

Or....inside your air valve there is, too, a series of seals that normally prevent air from getting from the air supply side into the exhaust side of the valve, and then out the exhaust port. And that air, as it gently (or not so....etc. ) is pouring your compressed air dollars from the plant air supply.

So, which is it that's leaking; the seal around the piston in the cylinder, or the seal inside the valve that stops the incoming air from getting across to the exhaust port without going up to the cylinder?

Have a look at the cylinder. If the rod is out, air will be entering the air port at the rear of the cylinder. If the cylinder is in - retracted, the air will be coming into the cylinder at the rod end.

Take the air line that is charged, that is, the air line that is supplying air to the cylinder, and crimp it. Many air lines are made of polyethylene or polypropylene, and it's quite easy to make a bit of a bend in the air line, effectively shutting off air to the cylinder.

Listen at the valve. If the air has stopped escaping the valve's exhaust port, then it's the seal in the cylinder that's at fault.

If, after ensuring that the air to the cylinder is completely stopped, air continues to exhaust from the exhaust port of the valve, then it's the seal inside the air valve that's at fault.

Regardless of which is the culprit, the air valve or the cylinder, get it fixed....fast! Compressed air costs a bundle. You don't want to waste it.

Published At: Isnare Free Articles Directory http://www.isnare.com
Permanent Link: http://www.isnare.com/?aid=45290&ca=Business+Management

How Air Duct Cleaning Improves Air Quality

2009-05-13T22:12:00.000+07:00

Air duct cleaning is the term commonly applied to the work performed by professional HVAC cleaning contractors. It’s a service that is necessary in order to provide clean air throughout commercial buildings and homes.

In business environments air duct cleaning is an important way to insure the comfort of employees for better work performance. It is important to clean air ducts occasionally to insure the safety and security of employees in the work place. Especially in cases where there is a need to remove harmful fumes.

Many believe air duct cleaning is as important as having clean running water. Buildings that don't have proper working air ducts tend to be very muggy and seem very damp. Air duct cleaning is one task that when performed, can help keep the indoor air safe and clean for residents to breathe.

Home owners are beginning to realize air duct cleaning is an important part of home maintenance and is essential to keeping their indoor air healthy.

Home owners should be aware that the air duct cleaning industry is not a federally regulated industry so it is very easy for people to get into business using substandard equipment, and inexperienced laborers and/or subcontractors. Most state and local authorities place no requirements on licensing or certifications.

Air duct cleaning can prevent health issues that relate to air quality and is becoming one of the ways people with health issues work to improve their overall indoor air quality and quality of life. Many people simply feel a proper air duct cleaning is well worth it, and a part of normal household maintenance.

If ducts are clogged with excessive amounts of dust and debris these pollutants are actually released into the home and of course breathed by the occupants.

You should consider having the air ducts in your home cleaned if there is substantial visible mold growth inside hard surfaces. If you have insulated air ducts and the insulation gets wet or moldy it cannot be effectively cleaned and should be removed and replaced.

If you do decide to have your air ducts cleaned, take the same consumer precautions you normally would in assessing the service provider's competence and reliability.

Do you know what's in the air you breathe? Improve your health and increase the efficiency of your heating and cooling system by having a whole house air duct cleaning. http://www.allcomfort-hvac.com/DuctCleaning.html

Article Source: http://EzineArticles.com/?expert=Clyde_Lee_Dennis

How to Buy a Refrigerated Compressed Air Dryer

2009-05-08T21:56:00.001+07:00

Many customers are often confused as to which kind of dryer for compressed air would work well for them. While some people prefer high-end brands, others may want to opt for more cost-effective solutions. No matter what your prerogative maybe you should consider the following aspects before purchasing any air dryer system.

Reputation of the brand

First and foremost, no matter which kind of dryer mechanism you are looking for, make sure the manufacturer enjoys a good reputation in the market. You may end up purchasing a lower end model at a cheaper rate but the downside to this is that your maintenance and repair costs may go up in the long term. Always select a brand, which is well versed with the compressed gas treatment domain. Most manufacturers of compressed air dryer mechanisms should enjoy a good level of customer service not just before the sale but also post sales as that is when it counts the most.

Feature sets

Once you have zeroed in on a particular brand, you want to explore the feature sets available in their range of air dryer mechanisms. Always opt for the latest heat transfer technology enabled systems as they deliver the best performance in the long-term. Make sure the dew point is as low as is possible and that it keeps all of the pneumatic equipment in top class condition. Look for a model, which offers maximum air drying capability. Only such a feature will help you maximize savings in terms of energy expenditures. Even if the compressed air dryer were to dry around 1000 SCFM you can expect a savings of at least 1000 USD each year, which is no small amount! Compared to a non-cyclic dryer, such models offer good cost-effectiveness. The proper cleansing of the compressed air is also crucial especially if you or any member of the family suffers from dust allergies. Always ask the retailer or the manufacturer if there are any special provisions to remove air-borne ingredients such as pollen etc. as these can trigger an asthma or respiratory attack.

Pricing

Price is almost always a major driver when considering to purchase an air drying system. However, it is also important not to go by merely price alone. You should also weigh the overall cost savings in the long term in comparison with the initial costs while purchasing the system. Most often, the more reputed the manufacturer is, the higher will be the cost of the dryer but at the same time efficiency and drying ability is much more, accounting for a large amount of electricity cost savings.

Not sure which kind of compressed air dryer you need to buy? Select from our vast array of superior, state of the art dryers manufactured by some of the best brands in the market today. In addition, our sales personnel are subject matter experts in the realm of the air dryer segment and can assist you with any query or concern you may have. So come visit us at Van Air Systems today!

Article Source: http://EzineArticles.com/?expert=Irina_Tischenko

Compressed Air Filters

2009-05-08T21:35:00.000+07:00

Compressed air filters are widely used in the industrial arena. They are used to remove water, oil, oil vapor, dirt and other contamination from a compressed air supply. Compressed air filters are used to control and cool various forms of industrial instruments. A pneumatically operated machine suffers serious effects caused by dirt particles, oil carryover and moisture. In most of the applications, contamination of the air supply could lead to serious performance degradation and most likely will increase the maintenance cost in terms of repairs. The result of this is that productive time is lost. The only way to cut down the costs and increase the performance is to properly maintain compressed air filters.

There are different types of compressed air filters. All of them are built in a way to remove the oil and other contamination from the air supply. Some have special features that make them more effective in specific applications. Coalescing oil removal filters are able to remove oil at the sub-micron level. General compressed air filters remove liquid and solid contaminations of various micron sizes. Adsorbent, oil vapor, removal filters are designed to maintain a very pure inflow. They use adsorbent materials such as charcoal as a filter media to reduce vapor less than 1ppm. These devices are used in conjunction with other instrumentation. Multi staged compressed air filters are also frequently used. A 10 m micron filter blocks any particle or droplet 10 microns and above in diameter. You'll find an extensive line of air filtration products on the Internet that will probably fit your needs. Just do a search for compressed air filters.

Air Filters provides detailed information on Air Filters, Home Air Filters, Car Air Filters, Electronic Air Filters and more. Air Filters is affiliated with Portable Air Compressors.

Article Source: http://EzineArticles.com/?expert=Marcus_Peterson

How to Tell When Your Compressor Needs an Air Dryer

2009-05-08T21:24:00.001+07:00

Ask a Question:

Can water or moisture be damaging my compressed air system?

Answer:

Absolutely! Water corrodes pipes, valves, machinery controls. None of this is good. When controls malfunction, production can stop or product can be impaired and all this costs you time and money.

Water in Aerosol or Vapor form is more difficult to remove and requires the use of a Compressed Air Dryer.

Ask a Question:

How does water or moisture get into my compressed air?

Answer:

Through your Compressor inlet.

Water vapor (humidity-moisture) enters the air system through the air compressor inlet air filter. The air compressor sucks in approximately 7 cubic feet of atmospheric air at 0 psig, and that volume of air is compressed into 1 cubic feet of air at 100 psig. The water vapor (humidity-moisture) that was in the 7 cubic feet of atmospheric air is now compressed into 1 cubic feet of compressed air.

There are 3 forms of water in compressed air:

-Liquid water
-Aerosol (mist)
-Vapor (gas)

Any of these forms of moisture can create problems down the road in equipment or may create serious problems in your process or end product today.

Ask a Question:

How to tell if you need a Refrigerated Air Dryer?

Answer:

If you are experiencing the following problems...then you may need a Refrigerated Compressed Air Dryer:

-Liquid water is in your air lines and hoses
-Water vapor sprays out of your tool exhaust
-Pipe lines corrode and rust
-Paint Sprayer has water spots in the paint
-Your Equipment Manufacturer specifies "DRY AIR"

Ask a Question:

What can help remove moisture from my Compressed Air System?

Answer:

Refrigerated Air Dryers can be one of the best solutions to removing water and moisture from your Compressed Air System.

Ask a Question:

How does a Refrigerated Air Dryer Work?

Answer:

• The refrigerated air dryer cools the incoming compressed air first in an air-to-air heat exchanger where the outgoing cool dry air pre-cools the hot incoming air and condenses some moisture out.

• Then the incoming air enters an air-to-refrigerant heat exchanger where the air is cooled to 38º F by the liquid refrigerant. This process causes the moisture to condense into liquid water and it is drained away. The out going air then enters the air-to-air heat exchanger and is warmed up to keep the outside of pipes from sweating.

• The refrigeration compressor pumps hot hi-pressure gas refrigerant (Freon) into the condenser which transfers the heat from the refrigerant gas to the ambient air as the gas condenses into a liquid.

• The liquid refrigerant (Freon) is then metered to a cold low pressure where it enters the air-to-refrigerant heat exchanger and the heat from the hot compressed air is adsorbed into the cold refrigerant (Freon). The refrigeration compressor then sucks low pressure hot gas refrigerant (Freon) into the refrigeration compressor and the cycle starts over again.

BOTTOM LINE: If you are experiencing unwanted moisture and water in your Compressed Air System, then seriously consider the addition of a Refrigerated Air Dryer. After all - what is the best way to spend your money --on constant maintenance, failed equipment and ruined end products or by investing in a properly sized compressed air dryer?

Experience proves it! Remove Water and Moisture to improve Compressed Air Quality & Efficiency!

Increase Production - less down time due to moisture related equipment problems
Reduce loss due to inferior products ruined by moisture in lines
Bring more profit to your bottom line

Learn More about Refrigerated Air Dryers http://www.airdryers.biz

Article Source: http://EzineArticles.com/?expert=Tommy_McGuire

Compressed Air Dryers and Refrigerated Air Dryers

2009-05-05T23:03:00.000+07:00

Compressed air dryers are being used in different industries. They are needed to ensure that the operations of machines are performing perfectly. However, there are so many of them in the market right now that coming up with the most ideal choice will always be very hard.

Nevertheless, there are the ones that stand out. When you want to buy compressed air dryers or refrigerated air dryers, you may want to choose any of the following:

Cycling Refrigerated Air Dryers. If you are looking for a device that will allow you to save as much as a thousand dollars for every piece of equipment that you buy per year, then the best option will be the cycling refrigerated air dryer. This one is able to maintain its dew point, even if it is performing below its design capacity. Since the total cost of energy will be dependent on the amount of air that is dried, you know that you are able to maximize on the performance and thus are able to save with these compressed air dryers.

High Inlet Temperature Dryer. There are also refrigerated air dryers that can perform a lot of functions. This way, you do not need to buy any more equipment. As its name suggests, the high inlet temperature dryer is able to not only function even when the temperature is already high, but it can also clean compressed air. You can also depend on it if you like dry compressed air. Simply put, everything you are searching for an air treatment system can be found in here.

Non-cycling Refrigerated Dryer. Do you have pneumatic machines with you? Then you may want to take your chances with non-cycling refrigerated air dryer. This one allows effective heat transfer so that the machine will function at its best. It can also maintain a constant dew point, between 35 and 38 degrees Fahrenheit. Like other kinds of compressed air dryers, this allows minimum operation costs.

Desiccant Dryers. Other kinds of air dryers are the desiccant dryers, which can reduce the dew point of your compressed air. They are able to accomplish this through water absorption. There are different types of desiccant air dryers that you can choose from. You have single-tower, twin towers, and regenerative desiccant dryers. Usually, people go for the twin towers since the first tower can dry the inlet air while the other regenerates the desiccant.

How to Buy Compressed Air Dryers

There are a number of things that you need to think of when you are thinking of buying compressed air dryers. For one, you have to determine how much air supply you need. You have to ensure the air dryer will not allow moisture to seep in to the air lines of your machine, leaving it as dry as possible. You also have to know the temperature of the area where you are going to use it. You may have to conduct a survey to be able to get an idea of the pressure dew point.

Van Air Systems has been the leading manufacturer and distributor of compressed air dryers and refrigerated air dryers. They are known not only for their efficient performance but also for their durability and easy installation. What's more, they permit maximum use of energy to make sure that you can reduce the energy costs.

Article Source: http://EzineArticles.com/?expert=Irina_Tischenko

Tips to Reduce Compressed Air System Pressure Drops

2009-05-05T22:59:00.001+07:00

Ask a Question:

What causes pressure drops in my compressed air system and how can I reduce them?

Answer:

Pressure drop can become a compressed air system problem that steals production time and money.

What causes pressure drops? Any type of obstruction, restriction, or roughness in the system will cause resistance to air flow and cause pressure drop.

In the distribution system, the highest pressure drops usually are found at the points-of-use, including undersized or leaking hoses, tubes, disconnects, filters, regulators and lubricators (FRLs).

On the supply side of the system, air/lubricant separators, aftercoolers, moisture separators, dryers and filters can be the main items causing significant pressure drops. The maximum pressure drop from the supply side to the points-of-use will occur when the compressed air flow rate and temperature are highest.

Your Compressed Air System components should be selected based upon these conditions and the manufacturer of each component should be requested to supply pressure drop information under these conditions.

When selecting filters, remember that they will get dirty. Dirt loading characteristics are also important selection criteria. Large end users who purchase substantial quantities of components should work with their suppliers to ensure that products meet the desired specifications for differential pressure and other characteristics.

The distribution piping system often is diagnosed as having excess pressure drop because a point-of-use pressure regulator cannot sustain the required downstream pressure. If such a regulator is set at 85 psig and the regulator and/or the upstream filter has a pressure drop of 20 psi, the system upstream of the filter and regulator would have to maintain at least 105 psig. The 20 psi pressure drop may be blamed on the system piping rather than on the components at fault. The correct diagnosis requires pressure measurements at different points in the system to identify the component(s) causing the excess pressure drop. In this case, the filter element should be replaced or the filter regulator size needs to be increased, not the piping.

Tips to Reduce Pressure Drop:

• Properly design the distribution system.

Minimizing pressure drop requires a "systems approach" in design and maintenance of the system.

Air treatment components, such as aftercoolers, moisture separators, dryers, and filters, should be selected with the lowest possible pressure drop at specified maximum operating conditions.

When installed, the recommended maintenance procedures should be followed and documented.

• Reduce the effective distance of the flow for air to travel through the system.

-Just like water in a garden hose --the longer the hose, the less water pressure at the end. It works the same with air.

-The pressure loss between the compressor and the end user tool comes from friction in the pipe. The smaller the pipe, the greater the friction, and the longer the pipe, the greater the friction.

If you have both of these issues in the same systems...you may have substantial pressure drops.

• Reduce the friction and restrictions.

-Pressure loss is caused by the friction of the air mass flowing on the side walls of the pipe or hose.

The larger the pipe, the more air it will carry in the center, not causing friction loss on the inside walls.

-A smooth inner lining of the pipe or hose will cause less pressure drop.

-A rough inner lining of the pipe or hose will cause more pressure drop. Pipe corrosion can cause friction and pressure loss.

-Couplings, fittings and valves increase the pressure drop.

-Make sure you have the most efficient system layout possible. You may need to relocate some equipment or re-pipe, but if you are suffering from excessive pressure drops, then the benefit may outweigh the cost.

• Reduce the velocity, or flow rate, of air through the system.

-For a given pipe or hose size and length, the pressure loss increases as the volume of air flow increases.

-Reducing and controlling the system pressure downstream of the primary receiver can result in a 10% or more reduction in energy consumption...even though the compressors discharge pressure had not been changed. Reducing your system pressure can help improve system performance, reducing leakage rates, and helping reduce stress on operating equipment. Note that a reduced system operating pressure may require modifications to other components, such as pressure regulators, filters, and the size and location of compressed air storage.

• Be sure to consider the effects of all your compressed air system's components on pressure.

-Operate and maintain air filtering and drying equipment to reduce the effects of moisture, such as pipe corrosion.

-Select aftercoolers, separators, dryers and filters having the lowest possible pressure drop for the rated conditions. It's important to check if manufacturers are including pressure drops in filters, pressure regulators, and hoses in their pressure requirements for end-use equipment, or if those pressure requirements given are for after those components. The typical pressure differential for a filter, pressure regulator, and hose is 7 psid, but it might be higher if the system is poorly maintained or designed.

-Specify pressure regulators, lubricators, hoses, and connections having the best performance characteristics at the lowest pressure differential. These components must be sized based upon the actual rate of flow and not the average rate of flow.

*SOURCES: "Improving Compressed Air System Performance: A Sourcebook for Industry" - a cooperative effort of the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE) Best Practices and the Compressed Air Challenge®; "Energy Savings in Compressed Air" by Hank Van Ormer.

Tommy McGuire

McGuire Air Compressors, Inc.

"Real People with Real Air Compressor Experience"

For Champion Air Compressors...
http://www.industrialaircompressors.biz/

For Reelcraft Hose Reels for Air, Water, Oil & fluid plus Electric Cord Reels & Welding Cable Reels...

http://www.hosereels.biz/

The Models of Industrial Air Compressors

2009-04-26T11:12:00.001+07:00

Industrial air compressors are used by many industries and manufacturers; some even depend on them. An industrial one is much more powerful than the type of air compressors that you would find around the regular household.

They are also much more expensive than their lightweight cousins. These air compressor system choices come in both gasoline models and electric models. Most industries use the gasoline models rather than the electric models, as the gas models reduce the utility costs.

Most industries choose to use the two-stage model of industrial air compressors for their tough, heavy duty tasks. The two stage system can store unused air for future use.

This type of compressor is also much more energy efficient and runs on a higher level of horsepower. More horsepower with these devices means that they work better and longer than the other models. They also break down far less often, which means that fewer hours of maintenance is needed on these units.

When purchasing any type of industrial air compressor, both safety and quality standards need to be considered. Most industries are required to purchase such compressors and compressor parts that are certified by the ASME, also know as the American Society of Mechanical Engineers. In the past few years there has been growing concerns about workplace safety.

This has prompted companies to be aware that they are purchasing high quality devices which have been certified. Many of the manufacturer companies out there are installing a safety valve that is used in case excess air pressure builds up in the unit.

If this happens, then the valve allows the air to be released automatically, which will decrease the pressure if there is a power overload. If the device does not have this safety measure, then it can explode.

Industrial air compressors are used mostly for industrial purposes, as they are the kings of the its world. These industrial compressors have much more power than their more compact counterparts and can be used for a wider variety of tasks.

While they are more heavy duty, they are also pricier, but again are not really appropriate for home use. Portable air compressors are more suitable for home use and can be moved about with more ease, allowing you to use it in more areas.

Mike Selvon has some great air compressors articles. Find out more tips on industrial air compressors at his resourceful site. We appreciate your feedback at our air compressor parts blog.

Article Source: http://EzineArticles.com/?expert=Mike_Selvon

Things to Consider When Purchasing a Portable Air Compressor

2009-04-26T11:09:00.000+07:00

Air tools can make your work much easier and efficient, and a portable air compressor is a necessity if you want to use them. Air compressors are available in many sizes and capacities. Some of the larger ones have wheels and handles to help move them around. They have different horsepower and pound per square inch (psi) ratings. They are typically powered by gas, electric, or diesel. The nice thing about the electric ones is that they can be used in spaces where you don't want to deal with the fumes. Of course, gas gives a high degree of reliability for frequent use, and is perfect when you need maximum portability. There's just not always a current bush around when you need one.

When you are in the market for a portable air compressor you need to take a look at your requirements. For example, if you are planning on using it for airbrushing, then a five liter tank capacity and approximately 30psi would be sufficient. If you need a larger volume of air then you obviously need something with a larger capacity. Otherwise, you'll be standing around waiting for your tank to fill up and that will not only decrease how efficient your work is, but it will also drive you crazy. I use a small pancake unit that works great for my brad nailer, but is constantly kicking on and refilling when I use the air blower attachment.

A portable air compressor is, well, portable. That means that you can move it around. So ask yourself how you'll be using it. If you need to fix the shingles up on the roof then portable is great. If you really just want something to fill the tires in the garage then maybe a portable unit will work, but you may want something with a higher capacity. Either way, just make sure you consider the various uses you may have before you buy.

Another thing to consider is your power source. Most air compressors in the US run on 110 volt, but some of the larger ones do run on 240 volt. Make sure to check in advance of your purchase. You should also consider the pump type you need. A belt driven pump is great for heavy use, and a direct-drive is designed for light use. The belt driven pump is quieter but needs the oil changed from time to time.

It may go without saying, but knowing the requirements of your air tools before you buy a portable air compressor is essential. Then, add a margin of safety of 50 percent. Each tool you have will have its CFM requirement on the box. The great thing about air tools is that they deliver more power with less weight and generally have a lower cost than regular electric tools. Always use proper eye protection and consider using ear plugs, especially with the gas-powered units.

How much does a portable air compressor cost? Well, like most things it can vary quite a bit. A basic setup can cost a couple hundred bucks, whereas a more powerful compressor with all the bells and whistles can run you into the thousands.

MJ is a free lance writer for Click Shops, Inc., where you can find the perfect portable air compressor for your specific needs at http://www.aircompressors.us.com

Article Source: http://EzineArticles.com/?expert=MJ_Marks

Analyzing Your Compressed Air System

2009-04-21T23:03:00.002+07:00

The first step in analyzing a compressed air system is to determine your compressed air needs. Compressed air needs are defined by the air quality and quantity required by the end uses in your plant. Assessing these needs carefully and understanding the difference between air quality and air quantity will ensure that a compressed air system is configured properly. Determining your pressure and demand load requirements are also important steps in analyzing your compressed air system.

Air Quality
Air quality is determined by the air dryness and contaminant level required by end uses. Learn the actual dryness level needed and the maximum contaminant level allowed for reliable production. Overtreating air beyond the required dryness and allowable contaminant level wastes money and energy.

Air Quantity
The required compressed air system volume can be determined by summing the requirements of your compressed air applications and process operations (taking into account load factors) and the duration of such volumes by those applications. The total air requirement is not the sum of the maximum requirements for each tool and process, but the sum of the average air consumption of each.

Pressure Requirements
The minimum required discharge pressure level must take into account the different pressure ratings of compressed air applications and processes as well as the pressure drops from components in the system. Too often, low or fluctuating pressure at end uses is misdiagnosed as not enough discharge pressure.

Pressure drop is a term used to characterize the reduction in air pressure from the compressor discharge to the actual point of end use. Pressure drop occurs as compressed air travels through the treatment and distribution system. Excessive pressure drop will result in poor system performance and excessive energy consumption. A pressure profile is a series of measurements of compressed air pressure at different points in the system, and allows identification of system components that are causing excessive pressure drop.

Demand Load Requirements
Another key to properly designing and operating a compressed air system is analyzing a plant’s compressed air requirements over time, or load profile. The variation of demand for air over time is a major consideration in system design. Plants with wide variations in air demand need a system that operates efficiently under part-load. In such a case, multiple compressors with sequencing controls may provide more economical operation. Plants with a flatter load profile can use simpler control strategies.

The following is a seven-step action plan from CAC Fundamentals of Compressed Air Systems to analyze and improve your compressed air system:

1. Develop a basic block diagram of your compressed air system.
2. Measure your baseline (kW, pressure profile, demand profile, and leak load) and calculate energy use and costs.
3. Work with your compressed air system specialist to implement an appropriate compressor control strategy.
4. Once controls are adjusted, remeasure to get more accurate readings of kW and pressures, and to determine leak load. Recalculate energy use and costs.
5. Walk through to check for obvious preventive maintenance items and other opportunities to reduce costs and improve performance.
6. Identify and fi x leaks and correct inappropriate uses – know costs, re-measure, and adjust controls as above.
7. Begin implementation of continuous improvement programs.

Source: http://www1.eere.energy.gov/industry/bestpractices/pdfs/compressed_air4.pdf

Energy saving - Using outside air for compressor intake

2008-01-12T10:11:00.001+07:00

The power consumed by a compressor is proportional to the specific volume, which is proportional to the absolute temperature of the gas at a given pressure. It is also clear that the compressor work is directly proportional to the inlet temperature of air. Therefore, the lower the inlet temperature of the air, the smaller the compressor work. Then the power reduction factor, which is the fraction of compressor power reduced as a result of taking intake air from the outside, becomes

f_reduction = (W_{comp, inside} - W_{comp, outside}) / W_{comp, inside}

f_reduction = (T_inside - T_outside) / T_inside

f_reduction = 1 - (T_outside/T_inside)

where T_inside and T_outside are the absolute tempertaure (in K or R) of the ambient air inside and outside the facility, respectively. Thus reducing the absolute inlet temperature by 5%, for example, will reduce the compressor power input by 5%. As a rule of thumb, for a specified amount of compressed air, the power consumption of the compressor decreases (or, for a fixed power input, the amount of compressed air increases) by 1% for each 3^oC drop in the temperature of the inlet air to the compressor.

Compressors are usually located inside the production facilities or in adjacent shelters specifically built outside these facilities. The intake air is normally drawn from inside the building or the shelter. But in many locations the air temperature in the building is higher than the outside air temperature, because of space heaters in the winter and the heat given up by a large number of mechanical and electrical equipment as well as furnaces year round.

The temperature rise in the shelter is also due to the heat dissipation from the compressor and its motor. The outside air is generally cooler and thus denser than the air in the compressor room even on hot summer days. Therefore, it is advisable to install and intake duct to the compressor inlet so that the air is supplied directly from the outside of the building instead of the insides. This will reduce the energy consumption of the compressor since it takes less energy to compress a specified amount of cool air than the same amount of warm air. Compressing the warm air in a building in winter also wastes the energy used to heat the air.

Read more..

Energy saving - Installing high efficiency motor

2007-12-26T14:37:00.000+07:00

The electric power required for the air compressor can be expressed as,

We can see that the electric power depends on the efficiency of the electric motor, thus, to install high efficiency motor we can save the energy as shown in the following equations,

where:
rated power = nominal power of the motor listed on its label (the power the motor delivers at full load)
load factor = the fraction of rate power at which the motor normally operates

The energy saving by replacing a motor by a high-efficiency motor can be calculated from,

Normally, the efficiency of a motor ranges between 70% to 96%. The loss is usually in the form of heat. Load factor also plays an important part in heat generation. Normally, high heat level is generated during part loading of a compressor.

Important considerations in the selection of a motor for a compressor

Operating profile of a compressor i.e. load vs time
Efficiency of the motor at part-load conditions
Efficiency of the motor at full-load conditions

One important rule to remember: "The efficiency of the motor decreases with decreasing load". See the following figure,

By the way, the efficiency of a motor at part-load conditions can be increased by installing a variable voltage controller.

Please keep in mind that oversizing is a bad practice beacuse the motor always operates at part-load conditions that gives lower efficiency of the motor.

Conclusion: "Using a small motor at full capacity is bettet than oversized motor, because the motors can handle occasional overloading well without any problems"

Energy saving - Repairing air leaks on compressed air lines

2007-12-26T13:24:00.000+07:00

What is the results of air leaks on compressed air lines?

An air compressor works harder
An air compressor works longer

The above undesireable results make the compressor consumes more energy.

Eventhough air leaks is unavoidable, but with good house-keeping factory, the level of air leaks of 10% is acceptable. Most of the factories have air leaks far beyond that what mentioned.

Air leaks normally occur at the joints, flange connections, elbows, valves, filters, hoses, etc. as a result of thermal cycling and vibration.

How to detect air leaks?

Listen for hissing sound -- in some factories, even when in production process, we can still hear this sound if the leakage rate is high
Apply soap water at the location where the air leaks may present
Using an acoustic leak detector
Pressure drop test

Mechanical energy wasted caused by air leaks

The following equation expresses the actual mechanical energy wasted due to air leaks

where: 1 < n < 1.4 (isentropic) and 0.7 < h_comp < 0.9

From knowledge of fluid dynamics, we know that when line pressure P2 > 2 atm, the velocity of air at the leak site is equal to the local speed of sound.

Thus, the mass flow rate of air through a leak can be expressed as,

where:
k = specific heat ratio = 1.4 for air
C_discharge = 0.65 (approx.)

From the above equations, you can calculate yourself to see how the energy is wasted through air leaks if the leak site has 3 mm diameter and the line pressure P_line is 5 bar. You will see that a lot of money is wasted!!

Read more details how to save the energy

Energy saving - How to calculate the cost savings

2007-12-26T13:03:00.000+07:00

The electric motor is usually the prime mover of the air compressors. Therefore, to save the energy of compressed air system is to save the energy consumption of the electric motor.

Energy saving of the electric motor can be written as shown in the following formula

Thus,

Cost savings = Energy savings x Unit cost of energy

Facts about energy saving of compressed air system

2007-12-26T12:01:00.000+07:00

"We are quick to identify energy losses from hot surfaces and to insulate those surfaces. But we are not so sensitive when it comes to saving compressed air, fixing air leask for instance, because most of the people think that the air is free-of-charge, but they don't reallize that to get the air at higher pressure than the atmospheric pressure requires considerable amount of work (energy)"

"The cost of electricity to operates the air compressor for one year can exceed the purchase price of the compressor"

In the next section we will see the cost of compressed air as well as the amount of energy wasted through the air leaks and so on.

Multi-stage compression with intercooling - Pressure ratio

2007-12-26T10:08:00.000+07:00

We know from the previous section that the minimum air compressor work is achieved with isothermal compression. In practical way, we try to achieve that by involving some cooling during compression process that leads to Polytropic compression process.

Normally, this can be achieved by dividing air compression into 2 stages. The first stage builds up the pressure from P1 to Px then the compressed air is cooled by the intercooler and the second stage compressor builds up the pressure again from Px to the final pressure P2. See the following figures to understand how the energy can be saved by using intercooling between each stage.

Fig.1 P-v diagram of polytropic compression process with intercooling

Fig.2 T-s diagram of polytropic compression process with intercooling

We can see from Fig. 1 that the amount of compressor work saved is related to the pressure Px.

What is the optimal value of Px that yields maximum compressor work saved?

The total compressor work, for this case, is the summation of compressor work of each stage as follows,

w_total = w_1 + w_2

We can see that w_total will be lowest when w_1 = w_2. Thus,

P1/Px = P2/Px

or

That means the pressure ratio of each stage should be identical to get the lowest amount of work required for air compression.

Air compressors work - Compression process

2007-12-25T00:47:00.000+07:00

To understand how to save the energy in compressed air system, it is useful to start with theory background of how the air compressors work and how the energy is consumed. As we know from Thermodynamic principle that the compressor work is,

where:
rev = reversible
in = input

Our objective is to minimize the air compressor work that means to approach the reversible process i.e. minimize the friction, and turbulence

Practical way to do this is to make v (specific volume) small by maintaining T (temperature) at low temperature during compression because v a T. In other words, to reduce the work input to a compressor, air should be cooled as it is compressed.

Effect of Cooling

Isentropic process: No cooling during compression
Polytropic process: Involve some cooling
Isothermal process: Involve maximum cooling

Which process yields the minimum required compressor work?
Let's consider the following equations of each process.

Assumptions:

All three processes are executed between the same pressure levels (P1 and P2)
Reversible process, gas behaves as an ideal gas (Pv = RT)

Isentropic process (Pv^k = constant, k = C_p/C_v)

Polytropic process (Pvⁿ = constant)

Isothermal (Pv = constant)

From the above 3 equations, we can plot them in P-v diagram as follows,

where:
Red line represents an isentropic compression process (n=k)
Blue line represents a polytropic compression process (1<n<k)
Green line represents an isothermal compression process (n=1)
Yellow area represents the air compressor work required during compression process of an isothermal process

Because the area from each line to the left is the required air compressor work, we can see that an isothermal process requires loweer amount of energy than polytropic process and isentropic process respectively.

Now we understand that we can save the energy required for compression if we could have some cooling during compression.

Next topic is to see how to save the energy in polytropic compression process which is the case of most air compressors.