installation guidelines for compressors guidelines for...equipment options to be used when ambient...

© 1999 Kaeser Compressors, Inc. All Rights Reserved

INSTALLATION GUIDELINES FOR COMPRESSORS

Compressed Air System Installation Guide


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Contents Section Page No. 1. Introduction 3 2. Location 3 3. Ventilation 6 4. Water-Cooling 10 5. Electrical Supply 10 6. Correct Air Storage 11 7. Efficiency Enhancing Equipment 12 8. Air Purity and Treatment 13 9. Disposal of Condensate 19 10. Compressed Air System Piping 23 11. Start-Up 27 12. Preventive Maintenance 28 13. Regulations/Health & Safety 29 Appendix A- Loss of Air Pressure Due to Friction 30



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1. INTRODUCTION Since it is a utility, compressed air is often taken for granted. Too often, compressed air systems are not given the same level of consideration as other plant equipment when planning a new installation. If you are planning a new facility, you have the opportunity to design an optimal compressed air system installation. Those who are upgrading an existing compressed air system often face many physical restrictions requiring creative solutions. In either case, whether you are modifying a compressed air system or planning a new system, the information contained in this guide will assist you in identifying the best configuration possible and getting the best possible performance from your compressed air system. Take advantage of the opportunity! You will be rewarded by a more energy efficient system that is easier to maintain and delivers the quality and quantity of air you need. For the purposes of this guide, it is assumed that you have identified the three critical parameters for any compressed air system: (1) pressure, (2) capacity and (3) air quality. These must be determined in order to properly size and select compressors, dryers, filters, piping, etc. If not, this guide contains some basic example applications and guidelines as to what level of air treatment is needed for each. We strongly recommend that your consult a compressed air specialist to accurately measure these parameters. Contact your Kaeser distributor for more information. Most of this guide is devoted to planning the layout and installation of your compressed air system. Emphasis is placed on providing you with an efficient, low maintenance system. It will also assist you in establishing compliance with safety and environmental regulations. This guide should be used as a supplement to the service manuals provided with your Kaeser compressed air equipment. These contain installation information pertaining to the specific model purchased. Diagrams in this guide are presented only as examples. They are not necessarily the best way of installing your particular system. If you need assistance, consult your Kaeser representative for expertise in installing compressed air systems. 2. LOCATION A. General Extreme temperatures (hot or cold), moisture and airborne contaminants can significantly affect compressor durability and air quality. For these reasons, we recommend installing compressors indoors. Because compressor noise is often cited as a reason to place compressors outdoors, Kaeser compressors come standard with full enclosures designed to significantly reduce noise levels. Sometimes, however, the ambient conditions inside a facility may be worse than outside. Excessive heat,



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dirt/dust, corrosive chemicals and other conditions may warrant outdoor installation. If outdoor installation is necessary, the compressor should at least be under a roof. Section D below identifies acceptable ambient conditions. Section E identifies equipment options to be used when ambient conditions are outside acceptable ranges. B. Floor No special foundation or anchoring is necessary for rotary screw compressors. The compressor should be placed on a level surface able to withstand the combined load of the compressor and the equipment used to move it into place.

C. Access The entrance to the compressor room must be large enough to accommodate both the compressed air equipment and the equipment used to move it into place (such as a forklift, crane, or pallet truck). The space designated for the compressed air equipment must provide enough clearance around it to:

• open maintenance doors and access panels • remove and replace components • install piping and air treatment equipment • provide adequate ventilation

Kaeser has designed its compressors so that internal components are easily accessible. Do not defeat this feature by blocking maintenance doors. Your Service Manual contains dimensional drawings for your specific model.

D. Environmental Considerations Temperature -- Avoid locating compressed air equipment in areas with ambient temperatures below 40° F or above 105° F. Low temperatures may impede the proper flow of some types of oil and promote undesirable condensation of moisture in control lines and other components. For lower ambient temperature applications, Kaeser offers options to protect the compressor including cabinet heaters and electric heat trace tape (refer to Optional Equipment section below). High ambient temperatures, on the other hand, often result in reduced lubricant life. They may also result in excessively high approach temperatures, which would hinder the cooling and condensation efficiency in the aftercooler and subsequent air treatment equipment. Ambient Particulate -- The Kaeser cabinet and pre-filter protect the compressor interior from most dirt and dust. In high dust areas it will be necessary to clean and replace the filters more often. In high dust applications, such as flour, cement, or talc production, an additional High Dust filtration option may be needed. See Section E. Moisture -- If possible, avoid exposing the compressor to excessive moisture (from humidity, rain, steam vents, dryer vents, etc.) in the ambient air. Excessive moisture



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can lead to electrical problems in the motor, promotes rust development on the cabinet and interior components, and hinders lubrication. Kaeser offers a number of options to allow compressor operation in wet/moist conditions, including motor winding heaters, rain hoods, and NEMA 4 doors (refer to the Optional Equipment section below). Corrosives -- Isolate the compressor from corrosive agents such as salt spray, ammonia, chlorine, and other chemicals. These may degrade the protective finishes on the cabinet, attack and erode internal components, and contaminate the lubricants and filters. E. Optional Equipment Cabinet heaters -- If the ambient temperature of inlet air ever drops below 40° F (but is still above 25° F), a cabinet heater must be installed. The cabinet heaters are designed to maintain the cabinet temperature at 40° F. This ensures proper oil flow during start-up and inhibits moisture collecting inside the cabinet. It is thermostatically controlled to shut off once the minimum operating temperature within the cabinet is reached. They are available from Kaeser factory installed or as a retrofit kit. Exhaust air re-circulation systems -- If your compressor is located such that it will be exposed to temperatures between 5° and 25° F, Kaeser suggests the installation of and exhaust re-circulation system. These are designed to duct compressor exhaust air back to the air inlet in order to maintain the minimum operating temperature and prevent freezing of moisture in the compressor components. Since compressors produce approximately 2550 Btu/hour per horsepower, the compressor is an excellent source of heating air. Although Kaeser can assist in sizing and designing of ductwork, it is recommended that you contact your local heating and air conditioning contractor for installation. Keep in mind that, at cold temperatures, after-coolers and control lines may freeze even when the compressor is running and the airend reaches the proper operating temperature. A combination of cabinet heater, electric heat-trace tape, and duct re-circulation may be necessary. High ambient temperature option -- Compressor components can be special ordered to operate in temperatures up to 126° F. These are not available as a retrofit.

Rain hoods – As stated, compressor should normally be installed indoors. If it must be installed outside they should have overhead protection from rain and snow. If no shelter is provided or if wind driven rain/snow can reach the compressor, rain hoods must be added to both air inlet and exhaust ends of the compressor cabinet exterior. They are available from Kaeser factory installed or as a retrofit kit. NEMA 4 doors -- NEMA 4 protection is necessary for the electrical control cabinet and instrument panel in order to protect electrical components from exposure to rain and dust. This feature is standard on AS, BS, CS & DS models and is an option on all others available factory installed or as a retrofit kit.



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Motor winding heaters -- In very wet or humid environments, a motor winding heater will prevent moisture from collecting and condensing within the compressor’s motor windings when the motor is off. Motor winding heaters shut off during operation. They are available from Kaeser factory installed. For information on any of the Kaeser options, consult your Kaeser distributor. 3. VENTILATION Air compressors, refrigerated dryers, and heated desiccant dryers produce large volumes of heat. Compressors produce approximately 2550 Btu per hp. If not removed from the compressor room, the ambient temperature will increase, reducing system efficiency and operator comfort. There are various ways to provide ventilation. Your choice will depend on several factors including:

• conditions in the compressor room • conditions outside • whether you intend to recover heat from the compressor

The following diagrams will provide some basic hints for proper ventilation. Detailed information concerning the proper ventilation for your compressor will be found in the Technical Specifications and Installation sections of your compressor’s Service Manual.



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For small compressors up to 15 HP, louvered inlets and outlets are often sufficient, as shown in Figure 3-1 below. Figure 3-1. Small Unit Ventilation

Outsideair

Exhaustto outside

Forced ventilation is usually required for compressors above 20 HP as shown in Figure 3-2 below. Figure 3-2. Forced Ventilation

ExhaustFan



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Figure 3-3 below shows a proper arrangement of multiple compressors. Figure 3-3. Proper Exhaust Flow

Do not place equipment so that exhaust from a compressor blows onto an air receiver, dryer, or into the air inlet of another compressor as shown in Figure 3-4. Figure 3-4. Incorrect Exhaust Flow



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Make provisions for freezing weather (if applicable); be able to restrict flow of cold outside air and re-circulate exhaust air until the compressor is running warm and can handle cold air. Adjustable louvers should be installed at the source of inlet air and where exhaust is discharged to protect units from extreme cold when not running or running under low load. Consider thermostatic control of the louvers. Duct work should have dampers to accommodate seasonal changes and heat recovery, if desired. Also, ensure that duct work connected to the compressor’s inlet and exhaust ends is easily removable for maintenance access.

U Do not weld duct work to the compressor. Coolers must be accessible for maintenance.

Figure 3-5. Ducting for Heat Recovery and Re-circulation

KAESER

FS 440

discharge to outdoors in summer

heating airfor plant

motorizeddampers

cooling airinto aircompressor

recirculate in winter

Refer to your compressor’s Service Manual or contact Kaeser for suggestions on duct work sizing for your particular compressor. For sizing, design, and installation of duct works, consult a qualified heating and air conditioning professional in your area.



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4. WATER-COOLING The use of water-cooled heat exchangers is optional on Kaeser’s AS through FS models (standard on GS and HS). However, water-cooling introduces several additional considerations, which can have significant impact on system design and installation. An adequate supply of suitable water and drainage is required. Depending on the source of cooling water, this may require special pumps and plumbing as well as filtration, water treatment, and chilling equipment. Customers who plan to install water-cooled compressors will receive water data forms to fill in. This data provides the Kaeser application engineers with detailed information about the source and characteristics of the water to be used, and enables them to select the proper cooling water piping and heat exchangers for each application. Contact your local Kaeser representative for assistance with water-cooled systems. 5. ELECTRICAL SUPPLY Before installing the compressor, check to ensure that your electrical service voltage matches the voltage on the compressor nameplate (located inside the electrical cabinet). If your compressor is a dual voltage model, ensure it is internally wired for the proper voltage.

U Actual operating voltage must be within +/- 10% of compressor name plate voltage. Damage or failures due directly or indirectly to insufficient or excessive voltage may not be covered under warranty. Consequently, Kaeser does not recommend operating a 230 volt system on a 208 volt circuit, for example. Kaeser recommends that each compressor have its own dedicated electrical circuit and disconnect panel. Electrically operated air treatment equipment should be powered through a separate circuit. Electrical planning should include wiring for a sequencer (multiple unit control device) and/or ComLink (remote control and monitoring device) if they are to be installed. The compressor should be properly grounded. Install an appropriately sized fuse or circuit breaker between the compressor and main electric service.



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U Never use air piping or electrical conduit as a means of grounding.

U All wiring and electrical connections must be performed by a qualified electrician in accordance with NEC and local electrical codes. Supply conductors must be properly sized in accordance with NEC and OSHA.

U For human safety purposes, the electrical service disconnect should be within sight of the compressor and have an easily recognizable lock-out tag.

6. CORRECT AIR STORAGE To optimize performance, Kaeser suggests the installation of two receivers. A “wet tank” will provide a steady source of controlled air, additional air cooling, and moisture separation. A “dry tank” stores clean dry air needed for demand surges. The “wet” tank should be installed after the compressor (but not in the exhaust air flow). This receiver will remove much of the moisture from your compressed air. By providing a stable volume of air, this receiver will also prevent excessive compressor cycling. This receiver also provides some protection for your downstream components from any oil slugs discharged from a malfunctioning compressor. The wet tank should be sized accordingly: a minimum of one (1) gallon per compressor(s) cfm at full load. The “dry” tank should be installed downstream of all air treatment components. This receiver is the main storage reservoir for your compressed air system and should be sized appropriately. Kaeser suggests providing between two (2) and four (4) gallons per cfm at full load. If a Sigma Air Manager or Controller is used, the system pressure sensors should be attached to the “dry” receiver. If your system includes a Kaeser Flow Controller (KFC), it should be installed immediately downstream of the “dry” tank. The KFC is a precision instrument that will stabilize pressure downstream at the desired level, reducing costly leaks and artificial demand. Use the following points as guidelines for installing “wet” or “dry” receiver tanks. Each receiver tank should be:

• ASME approved pressure vessels marked with the maximum working pressure rating. A receiver’s maximum pressure rating must meet or exceed the maximum system pressure.

• fitted with a good quality pressure gauge (Kaeser recommends large liquid filled gauges for accuracy).



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• fitted with a safety relief valve sized to handle the system’s pressure and total flow.

• fitted with a dependable drain trap at the lowest point. • fitted with an isolation valve at both the inlet and outlet ports. • installed in a cool area. Do not place receivers in path of compressor or dryer

exhaust flow. Doing so will re-heat the compressed air, reduce moisture separation, and possibly reduce the effectiveness of dryers and filters.

• installed as close to the point of use as possible. To prevent pressure drops caused by an intermittent heavy demand user, an auxiliary tank dedicated to this point of use is highly recommended.

7. Efficiency Enhancing Equipment. A. Sequencers/Air station managers -- Sequencers control multiple compressors more efficiently while maintaining system pressure within a narrow range, and ensuring they accumulate nearly equal service hours. The application of sequencers is ideal in two general circumstances: (1) The user has one compressor sized to meet full demand and has another compressor as a backup. In this situation, the sequencer alternates which is the base and which is the backup. (2) The user has multiple compressors to accommodate varying demand. The user will benefit from having multiple compressors each sized to meet the minimum demand. The sequencer will load additional compressors only when needed. This ensures the most economical use of electricity and eliminates excessive wear caused by frequent loading and unloading of single compressors sized to meet the highest demand. Another consequence is that compressors will not build up excessive service hours (reducing maintenance costs). The sequencer will also alternate the base and peak load compressors so they accumulate nearly equal service hours. In order for the compressors to accurately supply the demand pressure, the sensor for the sequencer air pressure switches should be placed as far down stream as possible, after all filtration and drying equipment. The “dry” receiver is an excellent choice. The sensor should be attached to the system manager using and adequately sized, shielded cable. Electrical Requirements- Kaeser system controllers require 115 VAC service. B. Kaeser Flow Controller-- The Kaeser Flow Controller (KFC) is a precision compressed air control instrument used to maximize system efficiency by reducing energy losses caused by leaks and artificial demand. It separates the supply side of the compressed air system from the demand side and provides stable pressure despite fluctuating demand.



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The KFC should be placed downstream of all air treatment equipment and receiver tanks. The KFC may also be used to separate different sections of a compressed air system that require different operating pressures. Orient the “IN” and “OUT” ports on KFC in accordance with the compressed air flow. Arrows cast into the control element indicate the proper direction of flow. The KFC can be installed in any plane. The headers are capable of supporting the weight of the unit for either vertical or horizontal mounting. Do not support the unit from the control elements or the associated control piping. If the unit was purchased without a manual or automatic bypass, install a three-way bypass with ball valves around the KFC to allow routine maintenance without interruption to plant air. Mount the control panel (if included) where most convenient within the following constraints. The panel is designed for top connections. Do not install the panel more than 150’ from the KFC header. Use 1/4” (outside diameter) pilot air tubing (copper is recommended) between the header and the control panel. It is critical that the pilot tubing and connections be leak free. If the optional Electronic Authority control panel is used, 115 VAC (single phase) service is necessary. A lug is provided for grounding the control panel enclosure. The electronic control panel must be grounded. 8. AIR PURITY AND TREATMENT The proper combination and order of filters, receivers, and dryers will ensure efficient elimination of moisture, oil, and particulate. Filters are available in various sizes and should be selected based on air flow ratings. Keep in mind that the stated performance of air treatment equipment is based on specific constant conditions (usually 70° F & 75% relative humidity) and may vary with temperature and relative humidity.



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A. Filters Below are descriptions of the Kaeser filters used in compressed air systems, with guidelines on where they should be placed. Like other compressed air system components, filters must be selected for the proper air flow and working pressure. Check unit serial number tags on the filters you receive to verify that the maximum working pressure is equal to or greater than your system operating pressure. See the Compressed Air Filters Instruction Manual for additional information concerning filter placement and maintenance. (Note: For the filters described below, “mist” is defined as fine liquid droplets. “Aerosols” are finer liquid droplets. “Vapors” are in gaseous form.) Kaeser Filtered Separator (KFS) • Designed for heavy liquid removal. • Flow range is 0 to 100%. • Removes all particles 3 microns and larger. • Removes 99+% of liquid water; 40% of oil aerosols. • Maximum liquid inlet concentration - 25,000 ppm. • 5 ppm oil carry over. • Maximum inlet temperature: 150° F. • Maximum working pressure: 250 psig up to 780 scfm; 225 psig for 1000 CFM and

above. • May be placed either before or after “wet” tank receiver, but prior to the dryer. • If a separate aftercooler is used, the KFS should follow it. Kaeser Particulate Filter (KPF) • Particulate and liquid removal. • Flow range is 0 to 100%. • Maximum liquid inlet concentration - 2000 ppm. • Removes all solid particles 1 micron and larger. • Removes 100% of liquid water; 70% of oil aerosols. • 1 ppm oil carry over • Maximum inlet temperature: 150° F. • Maximum working pressure: 250 psig up to 780 scfm; 225 psig for 1000 CFM and

above. • Placed before and after desiccant dryers (to remove desiccant dust). If the

desiccant dryer is heated, the High Temperature Afterfilter should be used downstream of the dryer (see below).

• Placed either before or after refrigerated dryers depending on type of dryer and operating environment. Consult a Kaeser representative.



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Oil Mist Eliminator (OME) • Coalescing type filter for aerosol removal with minimal pressure drop. • Removes all particles 3 microns and larger. • Removes 99.98% of particles 0.1 micron and larger. • Maximum liquid content after filtration: 0.5 ppm. • Pressure drop: 0.5 to 1.0 psi. • Cartridge life: 8 to 15 years. • Maximum liquid inlet concentration: 1,000 ppm. • Maximum inlet temperature: 150º F. • Placement depends on the application (i.e., liquid loading, required filtration). Kaeser Oil Removal Filter (KOR) • Coalescing type filter for fine water & oil aerosol removal. • Flow range is 0 to 100%. • Removes all solid particles 0.01 microns and larger. • Removes 99.99+% of oil aerosols. • Maximum liquid inlet concentration: 1000 ppm. • 0.01 ppm oil carry over (aerosol & vapor). • Maximum inlet temperature: 150° F. • Max. working pressure: 250 psig up to 780 scfm; 225 psig for 1000 CFM and above. • Placed after refrigerated dryer but before any type of desiccant dryer to protect the

desiccant from oil aerosols. • Use as a pre-filter ahead of desiccant and membrane dryers on systems supplied by

lubricated compressors to remove oil aerosols. • Use as an after-filter downstream of refrigerated dryers to remove additional liquid oil

aerosols formed in the dryer. Kaeser Oil Removal Extra Fine Filter (KOX) • Coalescing type filter for ultra fine water & oil aerosol removal. • Flow range is 0 to 100%. • Removes all solid particles 0.01 microns and larger. • Removes 99.999+% of oil aerosols. • Maximum liquid inlet concentration: 100 ppm. • 0.001 ppm oil carry over (aerosol & vapor) • Maximum inlet temperature: 150° F. • Maximum working pressure: 250 psig up to 780 scfm; 225 psig for 1000 CFM and

above. • Placed after refrigerated dryer but before any type of desiccant dryer to protect the

desiccant from oil aerosols. • Use as a pre-filter ahead of desiccant and membrane dryers on systems supplied by

lubricated compressors to remove oil aerosols. • Use as an after-filter downstream of refrigerated dryers to remove additional liquid oil

aerosols formed in the dryer.



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High Temperature Afterfilter (HTA) • Removes solid particles 1 micron and larger. • Maximum inlet temperature: 450° F. • Placed after heated desiccant dryers or anywhere large amounts of solid particles

are present in dry air. Kaeser Oil Vapor Adsorber (KVA) • Adsorbing type filter for gaseous oil, oil odor, and carbon dust removal. Removes oil

vapor below level detectable by smell or taste. • Removes all particles .01 microns and larger. • .003 ppm of oil carry-over (vapor). • Flow range is 0 to 100%. • Maximum inlet temperature: 150° F. • Maximum working pressure: 250 psig up to 780 scfm; 225 psig for 1000 CFM and

above. • No liquid should enter a KVA (KVA are not recommended for systems without

dryers). • Must be placed downstream of KOR/KOX in order to prevent oil saturation of KVA.

Introduction of any liquid into a KVA will compromise its ability to trap gases. If used in conjunction with desiccant dryer, the KVA follows the dryer and either a KPF or HTA, as appropriate.

Note: KFS, KPF, HTA, KOR, and KOX filters should be fitted with differential pressure gauges as a convenient visual indicator for when a filter cartridge needs replacement. Breathing Air System - The Kaeser Breathing Air System (BAS) is a complete air treatment system designed to provide OSHA Grade D breathing air. It includes the KPF, KOR and KVA filters as well as a desiccant dryer and carbon monoxide removal bed (See Figure 8-1). It should be installed far enough away from the compressor to allow the compressed air to reach ambient temperature before entering the BAS. It should not be subjected to liquid loads over 2000 ppm (properly maintained KPF and KOR filters will satisfy this requirement). The BAS should be sized to allow adequate flow and pressure for the application in accordance with OSHA (CSA in Canada) standards.

U Only air treated by a Kaeser Breathing Air System (or comparable competitive product) should be considered safe for breathing.



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B. Dryers Your selection of drying equipment should be based on the desired pressure dew point and ambient conditions. If your dryer or air lines will be exposed to freezing temperatures, for example, you will need a desiccant (or membrane) type dryer even if your pressure dew point requirements might normally be met by a refrigerated dryer. Ensure that dryers (and their drain traps) are rated for at least the maximum system working pressure and air flow. Dryers should be placed along the air line before any pressure reducing valves and after air has been cooled to 100° F or less (the combination of the after-cooler and “wet” tank achieves this). High air temperatures will reduce dryer efficiency and may increase power consumption (in refrigerated dryers). For this reason, do not place the dryer in the flow of the compressor exhaust. Use the following temperature guidelines for installing dryers:

Min. Ambient ºF Max. Ambient ºF Max. Inlet ºF Refrigerated Dryer 35 110 120 Desiccant Dryer 35 120 120

If your application requires any dryer to be installed in ambient conditions beyond these limits, consult Kaeser or your local distributor for information on how to prepare the equipment. To maximize drying effectiveness and reduce the load on the dryer, the dryer should be installed after a KFS filter (bulk liquid separator) and “wet” tank so that as much liquid as possible has already been removed. See figure 8-1 below. Desiccant dryers must be protected from oil aerosols and must be placed after an oil removal filter (KOR/KOX). See Figure 8-1 below. If using a refrigerated dryer in conjunction with a reciprocating compressor or other compressor with high oil carry-over, install a KPF prior to the dryer to prevent varnishing/fouling inside the dryer. C. Levels of Compressed Air Quality Figure 8-1 may be used as a quick reference for determining the selection and placement of air treatment equipment needed to achieve the air level quality for your application. When sizing air treatment equipment, consider that different sections of your plant may require different levels of compressed air quality. It is more economical to treat smaller amounts of compressed air for a particular application rather than to treat the entire air supply for the highest level of air quality needed.



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Figure 8-1. The Six Levels of Compressed Air Treatment



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9. DISPOSAL OF CONDENSATE A. General Condensate is formed as a result of compressing and then cooling air. On a 75° F day with 75% relative humidity, a compressor producing 100 cfm at 100 psig produces approximately 18 gallons of condensate per day. The higher the heat or relative humidity, the greater the volume of condensate produced. Most of this is water, but it is contaminated with some oil and particles from the compressed air system components and airborne particles drawn into the compressor. This condensate accumulates in receiver tanks, filters, dryers and piping. If it is not removed, it will be carried downstream with compressed air and contaminate both production equipment and products at the points of use. This may greatly increase your maintenance costs and product reject percentage. In addition, the condensate will saturate filter elements and render them useless. These costs far outweigh the costs of installing a dependable condensate system. A condensate system is made up of three elements: drain traps (attached to receivers, filters & dryers), an oil/water separator, and the piping that connects these. The following paragraphs describe the functions of these components. B. Drain Traps Drain traps are a critical, but often overlooked component in compressed air systems. Drain traps are the devices that remove condensate that accumulates in receivers, filters and dryers. They prevent the production contamination problems identified above. Drain traps must be properly sized to handle the volume of condensate generated, and they must be dependable. There are several types of drains, but they may be divided into two categories: manual and automatic. Manual drains are simply hand-operated valves. They are simple, but only as reliable as the person who opens them. They are inexpensive, but they have two significant drawbacks: they must be opened daily, and they waste energy by allowing compressed air to escape. Automatic drain traps open and close without human operation. They should be checked periodically to ensure they are operating properly but do not need daily attention as manual drains do. Automatic drain traps come in two basic types: timed and demand operated. Timed electric traps (TETs) are fairly inexpensive and simple. A timer operates a solenoid and opens the drain valve at preset intervals for a preset duration. Their main disadvantage is that they do not adjust interval or duration, regardless of how much condensate has accumulated. If very little condensate is present, TETs will allow



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compressed air to escape with the condensate, and introduce excess pressurized air into the condensate line. This creates turbulence within the line, which inhibits condensate separation at the separator. If there is more condensate forming than can escape during the preset duration, it will build-up in the system, possibly backing up into the air lines and contaminating production. Demand operated drain traps are simple mechanical devices that operate without electricity. They use floats to activate the drain valve when the condensate level reaches a certain level inside the trap. They prevent condensate build-up even in case of heavy liquid loading and do not discharge air with the water. Kaeser offers two types: the Automatic Drain Trap (ADT) and Automatic Magnetic Drain (AMD). Kaeser suggests using demand operated drain traps because they are reliable and minimize system pressure drops due to compressed air losses.

Drain traps should be installed on the following:

• Immediately after the compressor (when piping runs vertically) • Filtered Centrifugal Separators (KFS) or mechanical separators • All receivers • Particulate Filters (KPF) • Oil Removal Filters (KOR/KOX) • Oil Mist Eliminators (OME) • Refrigerated dryers. (Kaeser refrigerated dryers have drain traps built-in.)

The following do not require drain traps:

• Desiccant dryers • KPFs or HTAs installed after a desiccant dryers; however, manual drain valves

are recommended as an inexpensive way to check for proper dryer function. • Oil Vapor Adsorbers (KVA). Note that a manual drain valve is recommended in

order to de-pressurize the filter for maintenance and also to check for contamination/saturation.

Drain traps should be mounted below filters and should be fed from the lowest point possible on receivers and dryers. To prevent clogging of the drain trap orifices and mechanisms, Kaeser suggests installing a Y-strainer before drain traps. Also, a ball valve should be placed before the Y-strainer to enable maintenance personnel to isolate the strainer from pressure during cleaning. The use of a Y-strainer may not be necessary in conjunction with the AMD-6550 trap. The large orifice and the design of the mechanism make the AMD less susceptible to clogging than other traps. If using an AMD, install a ball valve in the condensate line to restrict and slow the flow of condensate into the header. The reason is that the large orifice on the AMD allows a larger volume through it, and if a pre-existing header is not large enough to allow the air to expand (pressure decrease), the flow may overwhelm the header. The ball valve



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may be adjusted to restrict the flow without backing condensate up into the trap. Use the AMD liquid level indicator as a guide to adjust the flow. C. Condensate Management System As mentioned above, condensate is not just water, but usually also contains oil and solid particles. The combination of oil and particulate often makes the condensate an environmentally hazardous material that must be properly disposed of. You may choose to collect all condensate in large vessels for disposal, but this is an expensive option. Typically, water makes up 95% of the condensate. It will be more economical to separate the water and pay only for the disposal of oils and other contaminants. These may be effectively separated at the end of the condensate system in a Condensate Management System (Kaeser’s CMS) or an equal performing oil/water separator. The CMS should be sized to handle the total volume of water collected in the system. Consider the flow demand as well as ambient heat and humidity when sizing the CMS. Allow for seasonal variations in heat and humidity. Water separated in the CMS may then be piped to a sanitary sewer drain using appropriately sized pipe. The separated water should be monitored to assure compliance with local, state, and federal environmental regulations. The separated oil must be recycled or disposed of properly in accordance with environmental regulations.

U Do not pipe the separated water into a storm sewer.



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D. Piping Condensate

Figure 9-1. Example Condensate Removal System

S

115 145

DS 140

Vent2” copper

3/8” copper

10 ft.

1 inch

CMS

AMD

Optional diffusiontank here

water drained tosanitary sewer

(Note: Pipe diameters shown in the above diagram are suggestions. Also, the height of the main condensate line is not drawn to scale. The vertical distance between drain traps and header line should not be greater than four feet in order to reduce the possibility of head pressure which would force condensate back through the drain traps into air treatment equipment.) Condensate drain traps must not share a common removal line because condensate from one filter could be pumped up into the next filter. These lines should be piped into a common header. To prevent condensate from one trap flow down into other traps, pipe the removal line into the top of the header. Kaeser suggests the use of flexible copper tubing for condensate removal lines and rigid copper pipe for the header. Plastic piping (e.g. ABS or PVC) is not recommended because it may be degraded by some synthetic lubricants. The header line should always slope down at a rate of one inch per ten feet as it approaches the Condensate Management System (CMS). Select a wide diameter header (at least 2”). This allows the air to expand and lose pressure before entering the CMS. The header line should be vented to eliminate pressure in the CMS. A simple and economical method is to connect a vertical piece of pipe to the header. The pipe must



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be long enough that condensate under pressure does not flow up out of its opening. A few feet is usually sufficient. Silencers/mufflers may also be used as vents. The vent can be placed at the high end of the header. It can also be installed at a T-junction where the horizontal pipe is the header, the downward pipe feeds the CMS and the upward pipe is the vent. Vents should not be placed close to where the line from a drain trap enters the header, otherwise condensate may be forced through the silencer. Applications with varying condensate output or in high relative humidity environments might benefit from a diffusion tank placed before the CMS. It allows condensate to drain into the CMS rather than be blown in under pressure, which may mix the condensate components and slow the separation process. The tank can be wall mounted directly over the CMS and feed into it (you can use the bolt holes in the feet to mount the tank). This provides a volume for expansion and pressure reduction. It also facilitates water/oil separation. A silencer can easily be installed in one of the tank fittings to vent all pressure. 10. COMPRESSED AIR SYSTEM PIPING Kaeser suggests using metal pipe. The correct sizing of pipe work is important to minimize system pressure losses. There are a number of tables available for estimating pressure drop due to friction loss at specific pressures. Appendix A contains the chart for 100-psig-system pressure. Note that the information in the chart is based on straight pipe that is smooth and clean inside. Pipe bends are an additional source of friction losses in compressed air piping. You will notice that pressure drop due to friction increases with flow. Every 2psig of pressure drop requires a 1% increase in input energy to maintain desired pressure. Another important consideration is leakage. Compressed air leakage accounts for a significant portion of compressed air energy costs (estimates range from 25-40%). By minimizing leaks you may save 25-40% on electricity. Consult your Kaeser distributor for assistance in obtaining this information for other pressures. A. Materials (1) Pipe • Iron pipe is a commonly used material for compressed air piping. It is durable and

moderately priced; however, it is subject to rust and scale, has a rough interior and requires threaded or welded joints (for 4 inch diameter and larger). Threaded joints are prone to leakage and also cause turbulence and friction which result in pressure drops. Galvanized iron pipe is an option that will reduce the rust and scale problems.

• Stainless steel is an excellent choice due to its smooth interior surface that does not rust or scale, but it is very expensive.

• Copper piping is often the best choice. Its smooth interior creates less pressure drop due to friction. Since it will not rust or scale there will be less contamination of



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the air. It is lighter and easier to install and change than iron. Because it is soldered and not threaded, it is less likely to leak. Overall, despite having a higher cost per foot than iron pipe, copper is often more economical when labor, air quality, leaks and pressure drop are considered. Kaeser suggests using silver solder. Soft solder should not be used with piston compressors (including boosters) due to the increased pressure and temperature.

• Kaeser does not recommend the use of PVC or ABS (plastics) because some synthetic lubricants degrade plastics, which may lead to pipe rupture. Also, air traveling through a plastic pipe may accumulate a significant static electric charge that could discharge at the point of use when an employee touches the air-driven tool.

Regardless of the type of piping material used, it must be rated for at least your maximum working pressure and meet all applicable codes. (2) Miscellaneous • Use couplings (connections, elbows, etc.) of the same material and pressure rating.

Seal threaded joints with a high quality pipe sealant in order to minimize leaks. • Minimize “T”s and right angles in order to reduce friction losses. Use rounded

elbows whenever possible. • Where “T”s are used, pipe the main flow through the head of the “T” and use the

stem to feed the bypass, air drop, etc. • Full-bore ball valves are recommended wherever valves are required. Ball valves

should be placed to facilitate future expansion of compressed air system (e.g., multiple compressors, more points of use).

• Use braces to secure piping to walls, floor, or ceiling to prevent movement of piping and stressing of pipe joints (which causes leakage).

B. At the Compressor • Discharge piping should be at least the same diameter as the compressor discharge

outlet. (See Figure 10-1) • A flexible pipe/hose connection between rigid air piping and compressor discharge

outlet is highly recommended in order to protect the aluminum discharge flange. (See Figure 10-1)

• A full-bore ball valve should be installed immediately after the flexible hose connection to isolate and maintain stored pressure downstream when compressor is serviced (See Figure 10-1). On large compressors (400 hp and higher) a high performance butterfly valve may be a less expensive and more convenient option. Also, an appropriate means of blow-down is required between the compressor and the isolation valve.

• Install an additional fitting (e.g. “Chicago” or “Dixon”) to allow temporary connection of mobile or backup compressor for uninterrupted air flow during maintenance/repair service. Figure 10-1 shows one possible location for this backup fitting. You may choose to place this fitting downstream of air treatment equipment in order to service



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the entire system at once. If so, you will need an alternate means to dry and filter the backup air in accordance with your needs.

Figure 10-1. Discharge Piping

union

braided (flex) pipe

shut-off valve

Chicago fitting forback up compressor

U Always open and close these valves slowly to avoid injury and equipment damage.

C. Air Treatment Piping Piping should enter receiver tanks low and exit high to promote maximum moisture separation and prevent accumulated condensate from migrating downstream. Kaeser filters are designed to allow quick access to the filter cartridges without disconnecting any piping. Do not run piping at heights that will put them out of reach or too close to the floor. Doing so will make filter replacement and proper installation of drain traps difficult. Refer to page 6 of the Compressed Air Filters Instruction Manual for dimensional information on your filters. To ensure ease of filter cartridge replacement, allow enough space under the filter to remove the filter bowl. This will eliminate the need to disconnect the entire filter from the inlet and outlet piping just to change filter elements. Mount KFS, KPF, and KOR filters so that inlet and outlet connections are horizontal and the filter bowls are vertical (as shown in Figure 8-1). Since separated and coalesced liquids drain by gravity downward inside the filters to the filter sump (and into the drain trap), the vessel must be mounted nearly plumb vertically, so that drainage will not be impeded.

U Ensure that the filter heads are installed so that air flows through the filter in the proper direction (as shown on the filter head).



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Use full-bore ball valves to isolate all air treatment items to facilitate routine maintenance without loss of compressed air. In applications where air quality is critical and the user cannot afford to shut down the compressed air system, each filter should have bypass piping with a redundant filter. The bypass must have ball valves to isolate it. With this configuration, the user may bypass filters during filter cartridge changes or other filter maintenance without compromising air quality. D. Distribution Piping Piping should be of sufficient diameter to minimize friction loss and allow for future expansion. Friction loss is related both to the type of pipe used (refer back to Materials) and the length of pipe. The chart in Appendix A may be used for estimating pressure drop. It is based on a pipe run of 1000 feet. Note that pressure drop is proportional to the length of piping, so a pipe run of only 500 feet will have half the pressure drop, for example. Airdrops to points of use should be fed from a loop system (rather than a dead end system). This effectively reduces air travel distances and ensures stable pressure to all points of use. Also, individual airdrops should exit the main pipe from the top so that condensed moisture will not enter the line. See Figure 10-2 below. Figure 10-2. Loop Distribution System

Avoid exposing air lines to freezing temperatures. If the air lines will be exposed to freezing temperatures, use a desiccant or membrane dryer.



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Figure 10-3 shows an individual airdrop to a point of use. Note that the air is piped from the top of the main line to minimize moisture at the point of use. Figure 10-3. Point Of Use Piping

Quick releasefitting for tool

Drip leg w/valve

Up and over piping reducesmoisture carry over

Filter, Regulator,& Lubricator(FRL)

Ballvalve

11. START-UP Prior to start-up, it is the installer’s responsibility to check that the equipment is installed in accordance with any specific instructions provided with each piece of equipment and that it meets all applicable federal, state, and local codes. The Kaeser representative who conducts the Start-Up will provide and complete the Compressor and Dryer Start-up Form, which includes the Installation Check List, Pre-Start-up Check List, and Dryer Start-up Check List. These will be retained for future reference and customer assistance. The customer will receive a copy of the entire form. In rare cases (such as very remote or overseas installations) when a Kaeser representative cannot attend the Start-Up, the form will be provided to the customer upon request and a Kaeser representative will assist the customer in completing the form via telephone or correspondence, if so desired. Equipment that is started after an extended shut-down period should be treated as a new start-up.



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12. PREVENTIVE MAINTENANCE All mechanical and electrical equipment requires varying degrees of attention to ensure that it operates efficiently. Since most customers rely heavily upon an uninterrupted supply of compressed air, it is sensible for them to invest in preventative maintenance rather than suffer costly downtime and repairs. It is highly recommended to establish a normal daily maintenance routine to ensure proper operation of all parts of your compressed air system. Regular preventive maintenance will ensure optimal performance and longer equipment life. Each system component (compressor, filter, dryer, drain trap, and CMS) has a service manual or guide with specific instructions on maintenance procedures and intervals. Follow all recommended maintenance procedures. Taking the few minutes each day to perform these checks will maintain the quality of your compressed air and your air driven tools, reducing the costs associated with repairs and lost production.

U Caution: Compressed air can be dangerous. Extreme care should be exercised at all times. Prior to performing any maintenance or service, system pressure must be vented at all points to ensure human safety. High pressure air should never be directed at anyone.. Valves should be opened and closed slowly to prevent damage to separators, filters, and controls caused by sudden surges of pressurized air.

In addition to the daily checks by your plant personnel, an effective preventive maintenance program should include regular professional servicing. Standard services are usually performed every 2,000 service hours, but may be recommended more often depending on the usage and operating environment.

U Lack of proper maintenance may invalidate any warranty claims if failures are directly related to a failure to perform routine preventive maintenance. A preventive maintenance contract with your local Kaeser distributor is a means of having this work carried out properly.



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13. REGULATIONS/HEALTH & SAFETY Installation should be conducted in a safe manner in accordance with OSHA and appropriate local regulations. Qualified technicians must perform electrical work in a safe manner using UL approved materials and properly insulated tools. A competent local authority should also inspect the work prior to starting equipment.

All pressure vessels must meet ASME and other appropriate local standards. The compressed air system must be installed so that normal operation poses no threat to worker health or safety. The system must be sufficiently ventilated so that it poses no heat threat to persons nearby. By design, rotary screw compressors are quiet; however, their operating environments may not be. Hearing protection must be worn in accordance with OSHA standards. Where applicable, prominently display signs warning of noise hazards. Compressor operating noise levels are listed in Kaeser service manuals. Condensate must be disposed of in accordance with local, state, and federal environmental regulations. Follow OSHA recommendations for electrical lock-out/tag-out and compressed air blow-down precautions. Kaeser offers other free guides filled with useful information about compressors and compressed air systems:

• Air Compressor Guide • Compressed Air System Guide • Compressed Air Treatment Guide • Energy Savings Guide

For these or other information, contact your local Kaeser representative.



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LOSS OF AIR PRESSURE DUE TO FRICTION (in psi in 1,000 ft. of pipe, *100-psi gauge initial pressure)

Cu.Ft free

air per min

Equivalent Cu.Ft.

compressed air per min

Nominal diameter, in.

1/2 3/4 1 1 1/4 1 1/2 2 2 1/2 3 3 1/2 4 4 1/2 5 6 8 10 12 10 1.28 6.50 0.99 0.28 20 2.56 25.9 3.90 1.11 0.25 0.11 30 3.84 58.5 9.01 2.51 0.57 0.26 40 5.12 . . . . 16.0 4.45 1.03 0.46 50 6.41 . . . . 25.1 6.96 1.61 0.71 0.19

60 7.68 . . . . 36.2 10.0 2.32 1.02 0.28 70 8.96 . . . . 49.3 13.7 3.16 1.40 0.37 80 10.24 . . . . 64.5 17.8 4.14 1.83 0.49 0.19 90 11.52 . . . . 82.8 22.6 5.23 2.32 0.62 0.24

100 12.81 . . . . . . . . 27.9 6.47 2.86 0.77 0.30

125 15.82 . . . . . . . . 48.6 10.2 4.49 1.19 0.46 150 19.23 . . . . . . . . 62.8 14.6 6.43 1.72 0.66 0.21 175 22.40 . . . . . . . . . . . . 19.8 8.72 2.36 0.91 0.28 200 25.62 . . . . . . . . . . . . 25.9 11.4 3.06 1.19 0.37 0.17 250 31.64 . . . . . . . . . . . . 40.4 17.9 4.78 1.85 0.58 0.27

300 38.44 . . . . . . . . . . . . 58.2 25.8 6.85 2.67 0.84 0.39 0.20 350 44.80 . . . . . . . . . . . . . . . . 35.1 9.36 3.64 1.14 0.53 0.27 400 51.24 . . . . . . . . . . . . . . . . 45.8 12.1 4.75 1.50 0.69 0.35 0.19 450 57.65 . . . . . . . . . . . . . . . . 58.0 15.4 5.98 1.89 0.88 0.46 0.25 500 63.28 . . . . . . . . . . . . . . . . 71.6 19.2 7.42 2.34 1.09 0.55 0.30

600 76.88 . . . . . . . . . . . . . . . . . . . . 27.6 10.7 3.36 1.56 0.79 0.44 700 89.60 . . . . . . . . . . . . . . . . . . . . 37.7 14.5 4.55 2.13 1.09 0.59 800 102.5 . . . . . . . . . . . . . . . . . . . . 49.0 19.0 5.89 2.77 1.42 0.78 900 115.3 . . . . . . . . . . . . . . . . . . . . 62.3 24.1 7.6 3.51 1.80 0.99

1,000 128.1 . . . . . . . . . . . . . . . . . . . . 76.9 29.8 9.3 4.35 2.21 1.22

1,500 192.3 . . . . . . . . . . . . . . . . . . . . . . . . 67.0 21.0 9.8 4.9 2.73 2.51 0.57 2,000 256.2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37.4 17.3 8.8 4.9 2.72 0.99 0.24 2,500 316.4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58.4 27.2 13.8 8.3 4.2 1.57 0.37 3,000 384.6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84.1 39.1 20.0 10.9 6.0 2.26 0.53 3,500 447.8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58.2 27.2 14.7 8.2 3.04 0.70 0.22

4,000 512.4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69.4 35.5 19.4 10.7 4.01 0.94 0.28 4,500 576.5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45.0 24.5 13.5 5.10 1.19 0.36 5,000 632.8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55.6 30.2 16.8 6.3 1.47 0.44 0.17 6,000 768.8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80.0 43.7 24.1 9.1 2.11 0.64 0.24 7,000 896.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59.5 32.8 12.2 2.88 0.87 0.33

8,000 1,025 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77.5 42.9 16.1 3.77 1.12 0.46 9,000 1,153 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54.3 20.4 4.77 1.43 0.57

10,000 1,280 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67.1 25.1 5.88 1.77 0.69 11,000 1,410 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30.4 7.10 2.14 0.83 12,000 1,540 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36.2 8.5 2.54 0.98

13,000 1,668 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42.6 9.8 2.98 1.15 14,000 1,795 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49.2 11.5 3.46 1.35 15,000 1,923 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56.6 13.2 3.97 1.53 16,000 2,050 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64.5 15.0 4.52 1.75 18,000 2,310 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81.5 19.0 5.72 2.22

20,000 2,560 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23.6 7.0 2.74 22,000 2,820 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28.5 8.5 3.33 24,000 3,080 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33.8 10.0 3.85 26,000 3,338 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39.7 11.9 4.65 28,000 3,590 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46.2 13.8 5.40 30,000 3,850 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53.0 15.9 6.17

* For longer or shorter lengths of pipe, the friction loss is proportional of the length, i.e., for 500 ft. one-half of the above; for 4,000 ft., four times the above, etc.

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