USACE / NAVFAC / AFCESA / NASA UFGS-22 15 26.00 20 (April 2006)
-------------------------------
Preparing Activity: NAVFAC Replacing without change
UFGS-15212N (August 2004)
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated January 2009
SECTION 22 15 26.00 20
HIGH AND MEDIUM PRESSURE COMPRESSED AIR PIPING
04/06
NOTE: This guide specification covers the requirements for non-breathing air
compressed air systems inside of buildings with pressures up to 34,470 kPa
(gage) 5000 psig.
Edit this guide specification for project specific requirements by adding, deleting,
or revising text. For bracketed items, choose applicable items(s) or insert
appropriate information.
Remove information and requirements not required in respective project, whether
or not brackets are present.
Comments and suggestions on this guide specification are welcome and should
be directed to the technical proponent of the specification. A listing of technical
proponents, including their organization designation and telephone number, is
on the Internet.
Recommended changes to a UFGS should be submitted as a Criteria Change Request
(CCR).
NOTE: Project requirements may require supplemental information added to the
paragraphs contained herein.
PART 1 GENERAL
1.1 REFERENCES
NOTE: This paragraph is used to list the publications cited in the text of
the guide specification. The publications are referred to in the text by basic
designation only and listed in this paragraph by organization, designation,
date, and title.
Use the Reference Wizard's Check Reference feature when you add a RID outside
of the Section's Reference Article to automatically place the reference in the
Reference Article. Also use the Reference Wizard's Check Reference feature
to update the issue dates.
References not used in the text will automatically be deleted from this section
of the project specification when you choose to reconcile references in the
publish print process.
The publications listed below form a part of this specification to the extent referenced. The publications are
referred to within the text by the basic designation only.
[AIR-CONDITIONING, HEATING AND REFRIGERATION INSTITUTE (AHRI)AHRI 520(2004) Performance Rating of Positive Displacement Condensing Units][AMERICAN WELDING SOCIETY (AWS)AWS D1.1/D1.1M(2008) Structural Welding Code - SteelAWS Z49.1(2005) Safety in Welding, Cutting and Allied Processes][ASME INTERNATIONAL (ASME)ASME B1.20.1(1983; R 2006) Pipe Threads, General Purpose (Inch)ASME B16.11(2005) Forged Fittings, Socket-Welding and ThreadedASME B16.20(2007) Metallic Gaskets for Pipe Flanges - Ring-Joint, Spiral Wound, and JacketedASME B16.34(2004) Valves - Flanged, Threaded and Welding EndASME B16.39(1998; R 2006) Standard for Malleable Iron Threaded Pipe Unions; Classes 150, 250, and 300ASME B16.9(2007) Standard for Factory-Made Wrought Steel Buttwelding FittingsASME B31.1(2007; Addenda 2008) Power PipingASME B36.10M(2004) Standard for Welded and Seamless Wrought Steel PipeASME B40.100(2005) Pressure Gauges and Gauge AttachmentsASME B46.1(2002) Surface Texture (Surface Roughness, Waviness and Lay)ASME BPVC SEC IX(2007; Addenda 2008) Boiler and Pressure Vessel Code; Section IX, Welding and Brazing QualificationsASME BPVC SEC VIII D1(2007; Addenda 2008) Boiler and Pressure Vessel Code; Section VIII, Pressure Vessels Division 1 - Basic Coverage][ASTM INTERNATIONAL (ASTM)ASTM A 106/A 106M(2008) Standard Specification for Seamless Carbon Steel Pipe for High-Temperature ServiceASTM A 182/A 182M(2008a) Standard Specification for Forged or Rolled Alloy-Steel Pipe Flanges, Forged Fittings, and Valves and Parts for High-Temperature ServiceASTM A 193/A 193M(2008b) Standard Specification for Alloy-Steel and Stainless Steel Bolting Materials for High-Temperature ServiceASTM A 194/A 194M(2008b) Standard Specification for Carbon and Alloy Steel Nuts for Bolts for High-Pressure or High-Temperature Service, or BothASTM A 269(2008) Standard Specification for Seamless and Welded Austenitic Stainless Steel Tubing for General ServiceASTM A 312/A 312M(2008a) Standard Specification for Seamless, Welded, and Heavily Worked Austenitic Stainless Steel PipesASTM A 351/A 351M(2006) Standard Specification for Castings, Austenitic, Austenitic-Ferritic (Duplex), for Pressure-Containing PartsASTM A 380(2006) Standard Practice for Cleaning, Descaling, and Passivation of Stainless Steel Parts, Equipment, and SystemsASTM A 403/A 403M(2007a) Standard Specification for Wrought Austenitic Stainless Steel Piping FittingsASTM A 53/A 53M(2007) Standard Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded and SeamlessASTM B 127(2005) Standard Specification for Nickel-Copper Alloy (UNS N04400) Plate, Sheet, and StripASTM B 164(2003; R 2008) Standard Specification for Nickel-Copper Alloy Rod, Bar, and WireASTM B 165(2005) Standard Specification for Nickel-Copper Alloy (UNS N04400)* Seamless Pipe and TubeASTM B 564(2006a) Standard Specification for Nickel Alloy ForgingsASTM E 11(2004) Wire Cloth and Sieves for Testing PurposesASTM E 381(2001; R 2006) Macroetch Testing Steel Bars, Billets, Blooms, and Forgings][MANUFACTURERS STANDARDIZATION SOCIETY OF THE VALVE AND FITTINGS INDUSTRY (MSS)MSS SP-58(2002) Standard for Pipe Hangers and Supports - Materials, Design and ManufactureMSS SP-69(2003; R 2004) Standard for Pipe Hangers and Supports - Selection and ApplicationMSS SP-71(2005) Standard for Gray Iron Swing Check Valves, Flanged and Threaded EndsMSS SP-80(2008) Bronze Gate, Globe, Angle and Check ValvesMSS SP-89(2003) Pipe Hangers and Supports - Fabrication and Installation Practices][NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA)NEMA ICS 2(2000; Errata 2002; R 2005; Errata 2006) Standard for Industrial Control and Systems: Controllers, Contractors, and Overload Relays Rated Not More than 2000 Volts AC or 750 Volts DC: Part 8 - Disconnect Devices for Use in Industrial Control EquipmentNEMA ICS 6(1993; R 2006) Standard for Industrial Controls and Systems EnclosuresNEMA MG 1(2007; Errata 2008) Standard for Motors and Generators][NATIONAL FLUID POWER ASSOCIATION (NFLPA)NFLPA T3.12.3 R2(1992) Pressure Regulator - Industrial Type][PIPE FABRICATION INSTITUTE (PFI)PFI ES 22(2002; R 2006) Color Coding of Piping Materials][SHEET METAL AND AIR CONDITIONING CONTRACTORS' NATIONAL ASSOCIATION (SMACNA)SMACNA 1650(1998; Addendum 2000) Seismic Restraint Manual Guidelines for Mechanical Systems - Second Edition][SOCIETY OF AUTOMOTIVE ENGINEERS INTERNATIONAL (SAE)SAE AMS7276(2001; Rev G) Rings, Sealing Fluorocarbon (FKM) Rubber High-Temperature Fluid Resistant Low Compression Set 70 to 80SAE AS4841(1995; R 2005) Fittings, 37 Degree Flared, Fluid ConnectionSAE AS4842(1995; R 2004) Fittings and Bosses, Pipe Threaded, Fluid ConnectionSAE AS4842/1(1995; R 2007) Fittings, 37 Degree Flared to Pipe Threaded, Fluid ConnectionSAE AS4843(1995; R 2007) Fittings, Beaded, Fluid ConnectionSAE AS4843/1(1995; R 2007) Fittings, Beaded to 37 Degree Flared, Fluid ConnectionSAE AS4843/2(1995; R 2007) Fittings, Beaded to Pipe Threaded, Fluid ConnectionSAE AS4875(1995; R 2007) Fittings, Straight Threaded Boss or Flanged to 37 Degree Flared, Fluid ConnectionSAE AS4875/1(1995; R 2007) Fittings, Straight Thread Boss or Flanged to 37 Degree Flared, Fluid ConnectionSAE AS4875/2(1995; R 2007) Fittings, Flanged to Beaded, Fluid ConnectionSAE J514(2004) Hydraulic Tube Fittings][THE SOCIETY FOR PROTECTIVE COATINGS (SSPC)SSPC SP 10(2007) Near-White Blast Cleaning][U.S. DEPARTMENT OF DEFENSE (DOD)MIL-C-15726(Rev F; Am 1) Copper-Nickel Alloy, Sheet, Plate, Strip, Bar, Rod, and WireMIL-T-16420(Rev K; Am 1) Tube, Copper-Nickel Alloy, Seamless and Welded (Copper Alloy Numbers 715 and 706)MIL-V-24109(Rev A) Valve, Globe, Angle, Quick Change Cartridge Trim, High Pressure (H.P.) Hydraulic and Pneumatic (Sizes 1/8 - 1-1/4 Inches)][U.S. GENERAL SERVICES ADMINISTRATION (GSA)FS A-A-1689(Rev B) Tape, Pressure-Sensitive Adhesive, (Plastic Film)FS A-A-58092(Basic) Tape, Antiseize, PolytetrafluoroethyleneFS A-A-60001(Basic) Traps, SteamFS QQ-B-654(Rev A; Notice 1) Brazing Alloys, SilverFS WW-S-2739(Basic) Strainers, Sediment: Pipeline, Water, Air, Gas, Oil, or Steam][U.S. NATIONAL ARCHIVES AND RECORDS ADMINISTRATION (NARA)29 CFR 1910.219Mechanical Power Transmission Apparatus]1.2 RELATED REQUIREMENTS
Section 23 03 00.00 20 BASIC MECHANICAL MATERIALS AND METHODS, applies to this section, with the additions and
modifications specified herein.
1.3 SUBMITTALS
NOTE: Review submittal description (SD) definitions in Section 01 33 00 SUBMITTAL
PROCEDURES and edit the following list to reflect only the submittals required
for the project. Submittals should be kept to the minimum required for adequate
quality control.
A “G” following a submittal item indicates that the submittal requires Government
approval. Some submittals are already marked with a “G”. Only delete an existing
“G” if the submittal item is not complex and can be reviewed through the Contractor’s
Quality Control system. Only add a “G” if the submittal is sufficiently important
or complex in context of the project.
For submittals requiring Government approval on Army projects, a code of up
to three characters within the submittal tags may be used following the "G"
designation to indicate the approving authority. Codes for Army projects using
the Resident Management System (RMS) are: "AE" for Architect-Engineer; "DO"
for District Office (Engineering Division or other organization in the District
Office); "AO" for Area Office; "RO" for Resident Office; and "PO" for Project
Office. Codes following the "G" typically are not used for Navy, Air Force,
and NASA projects.
Choose the first bracketed item for Navy, Air Force and NASA projects, or choose
the second bracketed item for Army projects.
Government approval is required for submittals with a "G" designation; submittals not having a "G" designation
are [for Contractor Quality Control approval.][for information only. When used, a designation following the
"G" designation identifies the office that will review the submittal for the Government.] The following shall
be submitted in accordance with Section 01 33 00 SUBMITTAL PROCEDURES:
SD-02 Shop Drawings
High pressure compressed air system
SD-03 Product Data
Air compressor
Air dryer
Instrumentation and controls
Air receivers [and] [separators]
Desiccant air dryers
Piping and tubing
Fittings
Valves
Adapters
Pressure gages
Snubbers
Timed solenoid drain
Traps
Filters
Strainers
Unions
O-ring gaskets
Flexible connections
Hangers and supports
Valve box
Identification labels for piping
For receivers[ and separators] include Manufacturer's Data Report Form U-1 or U-1A.
SD-06 Test Reports
Non-Destructive Examination (NDE) report for welding of piping
Leak tightness test
SD-07 Certificates
Employer's record documents
Welding procedures and qualifications
SD-08 Manufacturer's Instructions
Air receivers [and] [separators]
Include recommended certification test procedure and procedure for cleaning, external painting,
and delivery preparation.
SD-10 Operation and Maintenance Data
Air compressor, Data Package 4
Air dryer, Data Package 4
Submit in accordance with Section 01 78 23 OPERATION AND MAINTENANCE DATA.
SD-11 Closeout Submittals
Posted operating instructions for air compressor
Posted operating instructions for air dryer
Posted operating instructions for compressed air systems
1.4 QUALITY ASSURANCE
NOTE: The SMACNA Seismic Restraint Manual referenced in the paragraph below
shall be applied to locations subject to significant risk of seismic induced
loads. The degree to which this manual is to be used for contract drawings
and specifications shall be determined by the designer of record in coordination
with the NAVFAC Engineering Field Division's Mechanical Design Branch.
Provide all work specified in this section, including design, materials, fabrication, assembly, erection, installation,
and examination, inspection and testing of compressed air systems in conformance with ASME B31.1, ASME BPVC SEC VIII D1
[and ASME BPVC SEC IX] [ ASME BPVC SEC IX and SMACNA 1650], as modified and supplemented by this specification
section and accompanying drawings. In ASME B31.1, ASME BPVC SEC VIII D1 and ASME BPVC SEC IX, the advisory provisions
shall be considered mandatory, as though the word "shall" had been substituted for "should" wherever it appears;
reference to the "authority having jurisdiction" and "owner" shall be interpreted to mean the Contracting Officer.
1.4.1 Equipment Data
Submit the following data for equipment listed for "Operation and Maintenance Instructions, Parts and Testing."
a. Name and address of authorized branch or service department.
b. Characteristic curves.
c. Following applicable data completely filled in:
Manufacturer and model number [_____]
Operating speed [_____]
Capacity [_____] (CMS) (CFM)
Type of bearings in unit [_____]
Type of lubrication [_____]
Type and adjustment of drive [_____]
Capacity of tank [_____]
Electric motor: Manufacturer, frame and type [_____]
Motor speed [_____] rad/sec RPM
Current characteristics and kW HP of motor [_____]
[_____] Thermal cut-out switch: Manufacturer, type and model [_____]
Starter: Manufacturer: Type and model [_____]
1.4.2 High Pressure Compressed Air System
Show location, length, and type of welds or brazes, and indicate welding and brazing procedures to be used, preheat,
postweld heat treatment, and nondestructive welding and brazing testing required.
1.4.3 Laboratory Test Reports and Material Control
Laboratory Test Reports and Material Control for high Pressure Compressed Air Systems:
1.4.3.1 Laboratory Test Reports
Furnish the following laboratory test reports for pipe, tube, fittings, valves, and other pressure containing
components (except pressure gages) for each heat and lot of material.
a. Full chemical analyses.
b. Physical properties.
c. Etch test per ASTM E 381 as modified for the alloy to verify pipe and tube are seamless
and free of defects.
1.4.3.2 Material Control
Where more than one type of corrosion resistant alloy (stainless steel and copper-nickel or nickel-copper for
example) is to be installed at project site, the Contractor shall implement and maintain a material control system
with markings and/or tags to identify positively each piece as to the type of metal.
1.4.4 Welding Requirements
NOTE: The drawings should be checked to ensure that any supplementary information
required by the welding and Non-Destructive Examination (NDE) paragraphs has
been shown and that there is not conflict between the project drawings and the
specifications.
NOTE: Drawings must indicate, or test of the project specifications must specify,
the tensile strength, elongation, shear strength, size, length, type, and location
of the welds, as necessary.
Provide all welding work specified in this section for compressed air piping systems and in conformance with
ASME B31.1, as modified and supplemented by this specification section and the accompanying drawings. The welding
work includes: qualification of welding procedures, brazing procedures, welders, brazers, welding operators,
brazing operators, inspection personnel, nondestructive examination personnel, maintenance of welding records,
and examination methods for welds.
1.4.4.1 Butt Welded Joints
Butt welded joints shall be full penetration joints. Butt welded joints in systems with working pressures over
2068 kPa (gage) 300 psig shall be full penetration welds with consumable inserts or backing rings.
1.4.5 Employer's Record Documents
Submit to the ROICC for his review and approval the following documentation. This documentation and the subject
qualifications shall be in compliance with ASME B31.1.
a. List of qualified welding procedures that is proposed to be used to provide the work specified
in this specification section.
b. List of qualified welders, brazers, welding operators, and brazing operators that are proposed
to be used to provide the work specified in this specification section.
c. List of qualified weld inspection personnel that are proposed to be used to provide the
work specified in this specification section.
1.4.6 Welding Procedures and Qualifications
Determine performance qualification in accordance with ASME B31.1 and as specified.
1.4.6.1 Specifications and Test Results
Submit copies of the welding procedure
specifications and procedure qualification test results for each type of welding required. Approval of any
procedure does not relieve the Contractor of the responsibility for producing acceptable welds. Submit this
information on the forms printed in ASME BPVC SEC IX or their equivalent.
1.4.6.2 Certification
Before assigning welders or welding operators to the work, submit a list of qualified welders, together with
data and certification that each individual is performance qualified as specified. Do not start welding work
prior to submitting welder, and welding operator qualifications. The certification shall state the type of welding
and positions for which each is qualified, the code and procedure under which each is qualified, date qualified,
and the firm and individual certifying the qualification tests.
1.4.6.3 Renewal of Qualification
Requalification of a brazer or brazing operator shall be required under any of the following conditions:
a. When a brazer or brazing operator has not used the specific brazing process for a period
of 6 months.
b. There is specific reason to question his ability to make brazes that will meet the requirements
of the specifications.
1.4.7 Experience for Installation and Testing
Experience for Installation and Testing Of [Medium] [and] [High] Pressure Air System: Install and test [medium]
[and] [high] pressure air piping and equipment in accordance with ASME B31.1 and only with competent personnel
specially trained and experienced in installation and testing of [medium] [and] [high] pressure air systems.
The supervisors and personnel performing installation and testing shall have had previous experience in the satisfactory
installation and testing of at least two [medium] [and] [high] pressure air systems. Submit data substantiating
this experience to the Contracting Officer for approval prior to performing any work. Supervisors and personnel
with experience not acceptable to the Contracting Officer will be prohibited from working on these systems.
Experience data shall include the following.
a. Name of employee
b. Employer
c. List educational background and specialized training on installation and testing [medium]
[and] [high] pressure systems, including safety precautions.
d. List at least two installations of each type of system worked on and installed and tested
satisfactorily.
(1) Type of system and operating or design pressure; for medium pressure 869 to 2751 kPa (gage)
126 to 399 psig; for high pressure 2758 kPa (gage) 400 psig and higher.
(2) Company or owner.
(3) Location.
(4) Name, address, and phone number of a person who can be contacted for verification at the
installation.
e. If registered engineer, give the state in which registration is held, and branch of engineering.
An engineer is required to supervise safety during testing of medium and high pressure air systems.
1.4.8 Qualification of Pressure Vessel (Receiver) Inspectors
State Certification of Competency and active commission from the National Board of Boiler and Pressure Vessel
Inspectors (NBBI), Columbus, Ohio.
1.4.9 Training
Where special cleaning, flushing, material control, testing, and other special requirements are used on a contract,
such as required for high pressure compressed air systems, conduct formal training programs for employees on
the special requirements. Maintain records on such training which shall be available for inspection by the Contracting
Officer. Certify that employees have satisfactorily completed the required training prior to performing work
on the contract.
1.5 SAFETY PRECAUTIONS
1.5.1 Temperature Restriction
NOTE: The designer shall assure that the piping design temperature is not exceeded,
especially for high pressure systems. Provide aftercoolers and high temperature
shutdown devices as required for safe operation of the systems.
Compressors or other equipment shall not discharge compressed air to the piping systems above [38] [_____] degrees
C [100] [_____] degrees F unless approved by the Contracting Officer. Aftercoolers or other devices shall be
provided to comply with the temperature restriction.
1.5.2 Rotating Equipment
Fully guard couplings, motor shafts, gears and other exposed rotating or rapidly moving parts in accordance with
OSHA 29 CFR 1910.219. Provide rigid and suitably secured guard parts readily removable without disassembling
guarded unit.
1.5.3 Welding and Brazing
Safety in welding, cutting, and brazing of pipe shall conform to AWS Z49.1.
PART 2 PRODUCTS
2.1 HIGH PRESSURE AIR COMPRESSOR
NOTE: Prepare section for cooling water and include in project specification.
See Section 24 64 26 for piping and equipment which may be useful.
NOTE: Select aftercooler for 38 degrees C 100 degrees F discharge or design
special piping for higher temperature discharge. Paragraphs entitled "High
Pressure Air Piping for 34,470 kPa (gage) at 38 degrees C 5000 psig at 100 degrees
F System," and "High Pressure Air Piping for 20,682 kPa (gage) at 38 degrees
C 3000 psig at 100 degrees F System" are rated for 38 degrees C 100 degrees
F.
2758 to 34,470 kPa (gage)400 to 5000 psig system, multi-cylinder, multi-stage, [air] [water] cooled, reciprocating,
[belt][direct]-driven, base-mounted type, rated for continuous duty at [20,682] [_____] kPa (gage) [3,000] [_____]
psig and capacity indicated. Mount compressor, motor, controls, and instruments on a welded steel base plate.
[Provide means to adjust V-belt tension.] Provide splash lubricated compressor not to exceed 105 rad/sec 1000
rpm, or pressure lubricated compressor not to exceed 188 rad/sec 1800 rpm. Provide three phase squirrel cage
induction motor not exceeding 188 rad/sec 1800 rpm, with voltage characteristics as indicated, and open drip-proof
enclosure. Crankshaft and connecting rods shall be steel. Frame (crankcase), cylinders, and cylinder heads
shall be close grain cast iron. Fully enclose frame. Provide automatic unloaders to permit the compressor to
start unloaded. Provide [air] [water] cooled coolers after every stage of compression to cool discharge air
to within [4] [-7] [_____] degrees C [40] [20] [_____] degrees F of ambient air temperature. Provide automatic
condensate drains to drain condensate during operation and when the compressor stops. Conform to NEMA MG 1for
motor and NEMA ICS 2 and NEMA ICS 6 for controls.
2.1.1 Controls
NOTE: Select the first paragraph for only start-stop control or the second
paragraph and subparagraphs for dual control.
[Start-stop control compressors by means of pressure switches [and arrange for a lead compressor and a lag compressor].
[Lead] compressor shall start when the pressure falls to [17,235] [_____] kPa (gage) [2,500] [_____] psig and
stop when the pressure reaches [20,682] [_____] kPa (gage) [3,000] [_____] psig. [Lag compressor shall start
when the pressure falls to [13,788] [_____] kPa (gage) [2,000] [_____] psig and stop when the pressure reaches
[20,682] [_____] kPa (gage) [3,000] [_____] psig.] When both compressors stop at cutout pressure, the lead
and lag positions of compressors shall be interchanged automatically by means of an electric alternator.]
[Regulate compressor by dual control. Dual system shall consist of a combination of constant speed control and
an automatic start-and-stop control by automatic or manual selector switch.]
NOTE: Include "Start-and-Stop Control" and "Constant Speed Control" below only
for "Dual Control" option.
2.1.1.1 Start-and-Stop Control
When set for start-and-stop control, motor shall stop automatically when discharge pressure reaches maximum pressure
setting and start automatically when discharge pressure falls to minimum setting. Cylinders shall unload during
periods of motor shutdown.
2.1.1.2 Constant Speed Control
Compressor shall operate continuously at constant speed. Provide means to automatically load and unload compressor
at preset minimum and maximum pressure settings, respectively. Provide means for automatic release of pressure
within cylinders when the unit is operating without load. Also provide means for manual or automatic unloading
of cylinders during starting of unit. Equip compressor with a timed control to stop compressor after a 10-minute
unloaded period if air is not used.
2.1.2 Safety Controls
Provide safety controls to shutdown [each] compressor on high discharge air temperature or low oil pressure for
pressure lubricated compressor and low oil level for splash lubricated compressor. Set high temperature shutdown
at [54] [_____] degrees C [130] [_____] degrees F. Indicate each shutdown condition by a light on the compressor
control panel.
2.1.3 Accessories
Provide pressure gages and relief valves on intercoolers and on the aftercoolers. Provide [totally enclosed
belt guards,] discharge check valves, and pressure switches.
2.1.4 Noise
84 dBA maximum sound level one meter from compressor unit.
2.2 HIGH PRESSURE COMPRESSED AIR DRYER
Include component equipment, inter-connecting piping, wiring and controls, mounted in a cabinet and requiring
only the connection to utilities. Degrease dryer cabinet, prime coat, and finish coat with baked enamel. Contractor
shall furnish integral components whether specifically required by this specification or not. Air shall leave
the dryer at a temperature of [_____] degrees C F and a dew point of [_____] degrees C F, based on an inlet temperature
of [38] [_____] degrees C [100] [_____] degrees F. Pressure drop shall not exceed [21] [_____] kPa [3] [_____]
psi. Provide complete internal tubing, wiring, and piping, such that only connections to air inlet and outlet,
to refrigerant compressor contactor, and to condensate drain are necessary.
2.2.1 Construction
Heat sink type dryer consisting of a mechanical refrigeration system equipped with an automatic temperature shutdown
switch to prevent freezing, a large aluminum granule heat sink to allow a minus 16 degrees C 4 degree F automatic
temperature control, regenerative air to air exchanger, and main compressed air cooling exchanger. Refrigeration
system shall cool thermal mass heat sink which shall, in turn, lower compressed air temperature to dry air.
A direct air to refrigerant gas heat exchanger is not acceptable. Dryer shall have no internal traps or filters
and shall have large internal air passages to minimize pressure drop.
2.2.2 Air Circuit
Include the following:
a. Regenerative heat exchanger: ASTM A 269, Type 304L seamless stainless steel tube construction,
inlet compressed air to outlet compressed air heat exchanger designed to reduce cooling load
at design conditions minus 7 degrees C 20 degrees F by inlet air precooling.
b. Main heat exchanger: ASTM A 269, Type 304L seamless stainless steel tube construction,
single-pass, designed for minimum air pressure drop with air in the tubes surrounded by aluminum
granules.
c. Separator: Fabricated of ASTM A 269, Type 304L seamless stainless steel in accordance with
ASME B31.1. Code stamp is not required. Provide moisture separator, low velocity type, incorporating
change of air flow direction to prevent moisture carryover.
d. Dryer operating pressure: [20,682] [34,470] [_____] kPa (gage) [3,000] [5,000], [_____]
psig working pressure.
e. Drain line: Provide drain line to exterior of dryer with [condensate trap] [or] [automatic
drain valve].
f. Exterior piping connections: Provide with square ends.
2.2.3 Refrigeration System
Include the following:
a. Compressor: AHRI 520. Hermetic reciprocating compressor equipped with automatic start-stop
control, inherent motor protection, crankcase oil strainer, and suction screen. Refrigerant
shall be R-22.
b. Dryer controls: Capable of automatic 0 to 100 percent capacity control with an automatic
control expansion valve with sensing bulb to control capacity, with automatic shutdown switch
sensor located at point of lowest temperature to prevent freezing.
c. Air cooled condenser.
2.2.4 Instrumentation and Controls
Provide control panel in dryer cabinet containing:
a. Indicators:
(1) Inlet air pressure gage
(2) Discharge air pressure gage
(3) Inlet air temperature gage
(4) Main exchanger temperature gage
(5) Refrigeration compressor suction pressure gage
(6) Refrigeration compressor discharge pressure gage
(7) Power interruption light
(8) High temperature light
(9) Power on light
b. Electrical relays: Locate in an enclosed portion of panel, accessible for easy servicing.
c. Controls and interlocks:
(1) Condenser fan
(2) Compressor across the line contactor
(3) Thermostatic control switch
2.3 HIGH PRESSURE AIR RECEIVERS [AND] [SEPARATORS]
NOTE: Do not permit field welding on high pressure air receivers unless controls
over welding processes and nondestructive testing required by the military specification
can be implemented in the field.
ASME BPVC SEC VIII D1, constructed and stamped, seamless, forged, [20,682] [34,470] kPa (gage) [3,000] [5,000]
psig design working pressure, minimum safety factor of 4, corrosion allowance of [1.60] [_____] mm [1/16] [_____]
inch, straight thread, 0-ring sealed, forged steel inlet, outlet, and drain plugs, straight or angle connection
as indicated or required. [Capacity] [Capacities] as indicated. After heat treatment, examine exterior of vessel
by liquid penetrant or magnetic particle test; no defects are permitted. Furnish certified (non-destructive
examination) NDE report for high pressure air receiver. After hydrostatic testing at the factory, clean the
flask to oil-free condition. Abrasive blast interior and exterior to near white condition in accordance with
SSPC SP 10. Vacuum clean surfaces to remove dust and debris. Check surfaces with black light to ensure there
is no oil. Apply 2 or 3 coats of epoxy coating 0.20 mm 8 mils minimum dry film thickness, with white finish
coat for the interior and gray finish coat for the exterior. Provide certification of factory tests. Securely
support receiver and equip with pressure gage, drain valve, and ASME BPVC SEC VIII D1 and ASME BPVC SEC IX code
stamped pressure relief valve set as indicated and piped to discharge in a safe manner. Piping shall conform
to [20,682] [34,470] kPa (gage) [3,000] [5,000] psig standards. Provide each receiver with internal or external
blowdown and drain line with manual valve in accessible location, or with extension stem, discharging through
a visible open sight drain. Do not manifold cylinder drain piping together. Attachment welds to receiver [and
separator] shall not be permitted. Register vessel with NBBI and mark registration number on vessel.
2.4 MEDIUM PRESSURE AIR COMPRESSOR
NOTE: Prepare section for cooling water and include in project specification.
See Section 24 64 26 for piping and equipment which may be useful.
869 to 2751 kPa (gage)126 to 399 psig system. [Multi-stage] [Two-stage] [Single-stage], [air] [water] cooled
reciprocating, [belt] [direct] driven type, suitable for supplying compressed air at pressures indicated. Provide
compressor with ball or roller type bearing, pressure lubricated, thermal overload protection as required by
NEMA, pressure switch, inlet filter-mufflers, vibration isolators, intercoolers, aftercooler, and flexible connectors.
Provide safety control for shutdown and alarm on high discharge air temperature or low oil pressure. Capacity
and operating pressure as indicated on drawings. Mount compressor and motor on a base plate [and set on the
receiver. Design receiver for additional load of compressor and motor].
2.4.1 Receiver
Build receiver (tank) of welded steel, in accordance with ASME BPVC SEC VIII D1, Unfired Pressure Vessels, for
[2751] [_____] kPa (gage) [399] [_____] psig working pressure at [232] [_____] degrees C [450] [_____] degrees
F, complete with pressure gage, ASME BPVC SEC VIII D1 and ASME BPVC SEC IX code stamped safety valve, check valve,
shut-off valve on tank outlet, and automatic tank drain on tank. Provide tank with steel supports and bolt to
a concrete foundation. Capacity as indicated.
2.4.2 Motor and Starter
Provide motor and starter 40 degrees C 72 degrees F ambient temperature rise, continuous duty, drip-proof type
motor, ball bearings, for operation with current of voltage, phase, and cycle indicated on the electrical drawings.
Motor of such capacity that brake horsepower required by driven equipment at normal rated capacity will not exceed
nameplate rating of motor. Provide each motor with automatic, fully enclosed, magnetic starter. Conform to
NEMA MG 1 for motor and NEMA ICS 2and NEMA ICS 6 for starter and controls.
2.4.3 Controls
NOTE: Select the first paragraph for only start-stop control or the second
paragraph and subparagraphs for dual control.
[Provide start-and-stop control. Motor shall stop automatically when discharge pressure reaches maximum pressure
setting and start automatically when discharge pressure falls to minimum setting. Cylinders shall unload automatically
during periods of motor shutdown.]
[Regulate compressor by dual control. Dual system shall consist of a combination of constant speed control and
an automatic start-and-stop control by automatic or manual selector switch.]
NOTE: Include "Start-and-Stop Control" and "Constant Speed Control" below only
for the "Dual Control" option.
2.4.3.1 Start-and-Stop Control
When set for start-and-stop control, motor shall stop automatically when discharge pressure reaches maximum pressure
setting and start automatically when discharge pressure falls to minimum setting. Cylinders shall unload during
periods of motor shutdown.
2.4.3.2 Constant Speed Control
Compressor shall operate continuously at constant speed. Provide means to automatically load and unload compressor
at preset minimum and maximum pressure settings, respectively. Provide means for automatic release of pressure
within cylinders when the unit is operating without load. Also provide means for manual or automatic unloading
of cylinders during starting of unit. [Equip compressor with a timed control to stop compressor after a 10-minute
unloaded period if air is not used.]
2.4.4 Intercoolers and Aftercoolers
Provide intercoolers between all intermediate stages of multi-stage compressors and provide aftercoolers with
compressors. Intercoolers for air-cooled compressors shall be the tube-and-fin type. Intercoolers for water-cooled
compressors shall be the shell-and-tube type, except that tube-and-fin type may be used when the intercooler
is supported by the compressor frame or attached to the compressor. Air or water cooled intercoolers may be
the integral cast type when compressor is 19 kW 25 hp or less. Aftercoolers shall be of the water-cooled shell-and-tube
type or air-cooled tube-and-fin type. Water-cooled aftercoolers and intercoolers shall be of sufficient capacity
to cool the compressed air to within minus 9 degrees C and minus 7 degrees C 15 degrees F and 20 degrees F, respectively,
of the temperature of the water entering the coolers. Air-cooled intercoolers and aftercoolers shall have sufficient
capacity to cool the compressed air to within minus 7 degrees C 20 degrees F of the ambient temperature under
the atmospheric conditions indicated. Provide water-cooled intercoolers and aftercoolers with sight-flow indicator
to visually observe the flow of water to the cooler. The pressure drop of compressed air through the cooler
shall not exceed 7 kPa one psi. Provide intercoolers and aftercoolers with a moisture separator and drain trap
to remove the condensed moisture and oil from the air leaving the cooler.
2.4.4.1 Shell-and-Tube
Floating-head type consisting of a removable and cleanable nest of corrosion-resistant tubes within a steel shell.
Air may pass either through the tubes or the shell.
2.4.4.2 Tube-and-Fin
Copper, aluminum, copper-aluminum, or copper-alloy construction. Fins shall be securely bonded to the tubing.
Provide tube-and-fin coolers with a fan for circulation of the cooling air. The fan shall be adequately guarded
for safety and be driven either from the compressor crankshaft or by an independent electric motor.
2.4.5 Noise
84 dBA maximum sound level one meter from compressor unit.
2.5 MEDIUM PRESSURE Air receivers [and] [separators]
ASME BPVC SEC VIII D1, labeled and rated for [1896] [_____] kPa (gage) [275] [_____] psig, equipped with required
valves and trimmings, including gage and automatic drain valve and ASME BPVC SEC VIII D1 and ASME BPVC SEC IX
pressure safety relief valve. Pressure as indicated. [Sandblast exterior and interior to SSPC SP 10, near-white.
Lining shall be a factory applied 0.20 mm 8 mil minimum epoxy coating.] Exterior finish shall be [standard factory
finish] [two coats of rust inhibitor primer and one coat epoxy enamel].
2.6 MEDIUM PRESSURE COMPRESSED AIR DRYERS
NOTE: Make changes for medium pressure systems and insert the desired operating
pressure. Normally used for under 944 scms 2000 scfm capacity systems. CAUTION:
ASSURE CORRECT SYSTEM PRESSURE IS SPECIFIED.
Provide medium pressure compressed air dryers of the mechanical refrigeration type, equipped with an automatic
temperature shutdown switch to prevent freezing, a regenerative air to air exchanger (in capacity sizes above
5 to 28 scms 10 or 60 scfm as standard with the manufacturer), and a main compressed air cooling exchanger.
Refrigeration system shall cool compressed air to dry the air. Dryer shall have no internal traps or filters
and shall have pressure drop not greater than [21 kPa] [_____ kPa] [3 psi] [_____ psi] [indicated]. Air shall
leave the dryer at a temperature of [_____] degrees C F and dew point of [_____] degrees C F, based on an inlet
temperature of [38] [_____] degrees C [100] [_____] degrees F. Provide internal tubing, wiring, and piping complete,
such that only connections to air inlet and outlet, to refrigerant compressor contactor, and to condensate drain
are necessary.
2.6.1 Air Circuit
a. Regenerative heat exchanger: Inlet compressed air to outlet compressed air heat exchanger
(in capacity sizes above 5 to 28 scms 10 or 60 scfm as standard with the manufacturer) designed
to reduce cooling load at design conditions minus 7 degrees C 20 degrees F by inlet air precooling.
b. Main heat exchanger: Single-pass, with air in the tubes, heat sink, direct expansion, or
flooded cooler type.
c. Separator: Fabricated in accordance with ASME B31.1; code stamp not required; moisture
separator low velocity type incorporating change of air flow direction to prevent moisture carryover.
d. Dryer operating pressure: [1896] [_____] kPa (gage) [275] [_____] psig working pressure.
e. Drain line: Provide with exterior mounted condensate trap to facilitate servicing.
2.6.2 Refrigeration System
a. Refrigeration compressor: AHRI 520. Hermetic, semi-hermetic, or open reciprocating type
equipped with automatic start-stop or unloading capacity control; standard components include
inherent motor protection, crankcase oil strainer, and suction screen. Refrigerant shall be
R-22.
b. Dryer controls: Capable of automatic 0 to 100 percent capacity control. Refrigeration
controls shall maintain pressure dew point within the specified range without freezing of condensate.
Controls shall include such devices as capillary tube, expansion valve, suction pressure regulator,
thermostat, or other approved devices as standard with the manufacturer. Dryer shall have automatic
shutdown switch sensor located at point of lowest temperature to prevent freezing.
c. Refrigerant dryer and suction line strainer.
d. Air-cooled condenser, with condenser fan and motor.
2.6.3 Instrumentation and Control
Include control panel in dryer cabinet containing:
a. Indicators for the following services: Inlet air pressure gage, discharge air pressure
gage, inlet air temperature gage, main exchanger temperature gage, refrigeration compressor
suction pressure gage, refrigeration compressor discharge pressure gage, green "Power On" light,
power interruption light, and high temperature light.
b. Electrical relays: Locate in an enclosed portion of the panel, accessible for ease of servicing.
c. Controls and interlocks: To maintain required compressed air dew point and to cycle air-cooled
condenser with refrigeration compressor [while maintaining head pressure control with low ambient
temperature].
2.7 MEDIUM PRESSURE COMPRESSED AIR DRYER (CHILLED WATER TYPE)
NOTE: Edit for medium pressure systems and insert the operating pressure.
Chilled water air dryers are usually provided for 944 scms 2000 scfm and larger
capacities. CAUTION: Specify correct system pressure. If specification is
edited to use a dryer with direct heat exchange between air and refrigerant,
assure that air is not used for breathing since refrigerant leakage into the
compressed air may be hazardous to personnel; warning signs may be required.
Provide medium pressure compressed air dryer of the mechanical refrigerator type, with closed chilled water system,
regenerative air to air exchanger, and main compressed air to water heat exchanger. Refrigeration system shall
produce chilled water which, in turn, circulates through air-water exchanger to dry the air. Provide internal
tubing, wiring and piping complete, such that only connections to air inlet and outlet, to pump contactor, to
refrigerant compressor contactor, to condensate drain, and to air cooled condenser need be provided. Dryer shall
be suitable for a compressed air operating pressure of [1896] [_____] kPa (gage) [275] [_____] psig, with air
leaving temperature of [_____] degrees C F and dew point of [_____] degrees C F at rated pressure.
2.7.1 Air Circuit
a. Regenerative heat exchanger: Air to air exchanger, with inlet air passing through tubes
and outlet air in shell, designed to reduce cooling load at design conditions by precooling
inlet air minus 7 degrees C 20 degrees F.
b. Main heat exchanger: Shell and tube construction, single-pass, with air in tubes and water
in shell, designed for minimum air pressure drop, flanged connections, tubes rolled into tube
sheets, and ASME BPVC SEC VIII D1 and ASME BPVC SEC IX Code stamped.
c. Separator: Fabricated of carbon steel to ASME BPVC SEC VIII D1and ASME BPVC SEC IX Code
and stamped.
d. Drain: With condensate trap.
2.7.2 Chilled Water Circuit
a. Circulating pump: Single stage, mechanical seals, electric motor driven with line shut-off
valves.
b. Liquid cooler: Direct expansion, refrigerant in tubes, water in shell, designed for 2068
kPa (gage) 300 psig working pressure, removable tube bundle, ASME BPVC SEC VIII D1 and ASME BPVC SEC IX
Code stamped and insulated with foam type insulation.
c. Expansion tank: With sight glass, vent, and fill cock.
d. Flow switch: To shut down refrigeration compressor on loss of chilled water flow.
2.7.3 Refrigeration System
a. Refrigeration compressor: AHRI 520. Hermetic or semihermetic reciprocating type, with
183 rad/sec 1750 rpm motor, integral capacity control, oil pressure pump, oil scavenger pump,
full-flow oil filter, oil sight glass, inherent motor protection, crankcase heater, suction
and discharge service valve, crankcase oil strainer, Monel suction screen, and hot gas bypass
capacity control below last step of unloading. Refrigerant shall be R-22.
b. Accessories: Include a discharge line muffler, sight glass, refrigerant dryer, solenoid
valve, thermostatic expansion valve, and suction line strainer.
c. Air-cooled condenser: As indicated. Complete air-cooled condenser factory-fabricated and
assembled unit consisting of coils, fans, and electric-motor drive. Base capacity at design
conditions on minus 7 degrees C 20 degrees F temperature differential between entering air and
condensing refrigerant. Saturated refrigerant condensing temperature not over 40 degrees C
105 degrees F. Base entering dry bulb outside air temperature on [32] [_____] degrees C [90]
[_____] degrees F. Do not take subcooling into account in determining compressor and condenser
capacities. Air-cooled condenser may be used for refrigerant storage in lieu of a separate receiver,
provided that condenser storage capacity is 20 percent in excess of fully charged system. [Provide
head pressure control during low ambient temperature.]
2.7.4 Instrumentation and Control
Provide a control panel on the dryer containing:
a. Pressure gages (114 mm4 1/2 inches diameter) for the following services:
(1) Inlet air
(2) Condenser water inlet
(3) Refrigeration compressor suction
(4) Refrigeration compressor oil pressure
(5) Outlet air
(6) Condenser water outlet
(7) Refrigeration compressor discharge
b. Electrical relays: Locate in an enclosed portion of the panel, accessible from front of
panel.
c. Start-stop buttons and green running indicating light.
d. Controls and interlocks
(1) 115-volt control transformer
(2) Circulating pump across the line contactor
(3) Compressor across the line contactor
(4) Condenser water pressure safety switch
(5) Freeze protection safety switch
(6) Pump-out relay with normally open and normally closed contacts
(7) Oil safety switch
(8) Four stage thermostatic control
(9) Refrigerant dual pressure switch
2.7.5 Temperature Indicators
a. Air inlet
b. Air outlet
c. Chilled water in
d. Chilled water out
e. Dew point
2.8 DESICCANT AIR DRYERS
Chamber of welded steel, [_____] kPa (gage) psig working pressure, ASME labeled conforming to ASME BPVC SEC VIII D1
, with flanged or threaded fittings, and [manual] [automatic] drain valve. Manufacturer's recommended desiccant
in tablet form which will not nest or cake. Contractor shall provide a supply of desiccant for initial operations
in unbroken shipping containers equal to not less than four charges of desiccant for the dryer.
2.9 HIGH PRESSURE (HP) AIR PIPING AND ACCESSORIES
NOTE: The high pressure air system materials listed are tentative suggestions.
The designer shall calculate required minimum wall thicknesses for pipe and
tube in accordance with ASME B31.1 and verify adequacy of the materials listed.
Select material for corrosion resistance required in the service environment.
Allowance for corrosion or fabrication, factor "A" in ASME B31.1, paragraph
104.1, shall be selected by the designer. If carbon steel is selected as the
piping material, special attention should be given to the corrosion allowance
for the higher pressures such as 20,682 kPa (gage) 3000 psig and 34,470 kPa
(gage) 5000 psig systems since commercial sizes per ASME B36.10M would not permit
selection of large corrosion allowance factors.
2.9.1 HP Air Piping and Tubing
HP air piping and tubing for 34,470 kPa (gage) at 38 degrees C 5000 psig at 100 degrees F system shall conform
to the following:
a. Stainless steel pipe: ASTM A 312/A 312M, seamless stainless steel, annealed Type [304L]
[316L], Schedule 160 up to 25 mm one inch IPS, double extra strong (XXS) for 32 to 65 mm 1 1/4
to 2 1/2 inches IPS [,larger sizes shall be special as indicated]. Wall thickness "schedule"
and "weight" designations shall conform to ASME B36.10M. Fittings for pipe 40 mm 1 1/2 inches
IPS and smaller: ASTM A 403/A 403M, ASME B16.11, forged stainless steel, Type [304L] [316L],
socket welding, Class 6000 for 6 to 25 mm 1/4 to one inch IPS, Class 9000 for 32 and 40 mm 1
1/4 and 1 1/2 inches IPS. Fittings for pipe 50 to 65 mm 2 to 2 1/2 inches IPS: ASTM A 403/A 403M
, ASME B16.9, butt welding, seamless wrought stainless steel Type [304L] [316L], double extra
strong (XXS).
b. Nickel-copper pipe: ASTM B 165, seamless, annealed, Schedule 160 up to 25 mm one inch IPS,
double extra strong (XXS) for 32 to 80 mm 1 1/4 to 3 inches IPS, [,larger sizes shall be special
as indicated.] Wall thickness "schedule" and "weight" designations shall conform to ASME B36.10M
. Fittings 40 mm 1 1/2 inches IPS and smaller: ASME B16.11, forged nickel-copper ASTM B 564
, socket welding, Class 6000 for 6 to 25 mm 1/4 to one inch IPS, Class 9000 for 32 and 40 mm
1 1/4 and 1 1/2 inches IPS. Fittings for pipe 50 mm 2 inches IPS and larger: ASME B16.9, butt
welding, seamless wrought 70-30 nickel-copper, double extra strong (XXS), 50 to 80 mm 2 to 3
inches IPS.
NOTE: Use only one type of fitting for the entire project.
c. Stainless steel tubing: ASTM A 269, stainless steel, Type [304] [304L] [316], seamless,
annealed, with wall thicknesses as specified below. Fittings for tubing: stainless steel,
Type [304] [304L] [316], conforming to [SAE AS4841,] [SAE AS4842,][SAE AS4842/1,][SAE AS4843
,][SAE AS4843/1,][SAE AS4843/2,][SAE AS4875][SAE AS4875/1,][SAE AS4875/2,][SAE J514,] flared
type, suitable for 34,470 kPa 5000 psi service. Fittings shall have a minimum burst strength
of 138 MPa (gage) 20,000 psig; furnish laboratory burst test reports. Do not use flareless
fittings or bite type fittings. Do not weld tubing.
MINIMUM WALL THICKNESS FOR STAINLESS STEEL TUBING
Size (mm O.D.) Thickness (mm)
10 1.47
15 2.11
16 2.41
20 3.05
MINIMUM WALL THICKNESS FOR STAINLESS STEEL TUBING
Size (Inches O.D.) Thickness (Inches)
3/8 .058
1/2 .083
5/8 .095
3/4 .120
d. Copper-nickel tube: MIL-T-16420, Composition 70-30, temper-annealed, Type I - seamless
Class 6000 (41,364 kPa (gage)6000 psig working pressure), Grade 2 (material with heat identification),
IPS outside diameter sizes. Fittings 40 mm 1 1/2 inches IPS and smaller: ASME B16.11, MIL-C-15726
, forged copper-nickel, socket welding, except that body wall thickness shall not be less than
the minimum wall thickness for the size listed in MIL-T-16420 for Class 6000, and the average
socket wall thickness shall be 1.25 times, and the minimum socket wall 1.09 times the minimum
wall thickness for that size listed in MIL-T-16420 for Class 6000. Fittings 50 to 80 mm 2 to
3 inches IPS: ASME B16.9, butt welding, seamless wrought 70-30 copper-nickel, with minimum wall
thickness as listed for that size in MIL-T-16420 for Class 6000.
2.9.2 High Pressure Air Piping
High pressure air piping for 20,682 kPa (gage) at 38 degrees C 3000 psig at 100 degrees F system shall conform
to the following:
a. Stainless steel pipe: ASTM A 312/A 312M, seamless stainless steel, annealed Type [304L]
[316L], Schedule 80 up to 25 mm one inch IPS, Schedule 160 32 to 150 mm 1 1/4 to 6 inches IPS.
Wall thickness "schedule" and "weight" designations shall conform to ASME B36.10M. Fittings
for pipe 40 mm 1 1/2 inches IPS and smaller: ASTM A 403/A 403M, ASME B16.11, forged stainless
steel, Type [304L], [316L], socket welding, Class 3000 for 6 to 25 mm 1/4 to one inchIPS, Class
6000 for 32 and 40 mm 1 1/4 and 1 1/2 inchesIPS. Fittings for pipe 50 to 150 mm 2 inches to
6 inchesIPS: ASTM A 403/A 403M, ASME B16.9, butt welding, seamless wrought stainless steel Type
[304L] [316L], Schedule 160.
NOTE: Use only one type of fitting for the entire project.
b. Stainless steel tubing: ASTM A 269, stainless steel, Type [304] [304L] [316], seamless,
annealed, with minimum wall thicknesses as specified below. Fittings for tubing: stainless
steel, Type [304] [304L] [316], conforming to [SAE AS4841,] [SAE AS4842,][SAE AS4842/1,][SAE AS4843
,][SAE AS4843/1,][SAE AS4843/2,][SAE AS4875,][SAE AS4875/1,][SAE AS4875/2,] [SAE J514,] flared
type, suitable for 20,682 kPa 3000 psi service. Fittings shall have a minimum burst strength
of 139 MPa 20,000 psig; furnish laboratory burst test reports. Do not use flareless fittings
or bite type fittings. Do not weld tubing. Brazed 20,682 kPa 3000 psi tubing fittings may
be used where flared fitting connections are not required for equipment. Use FS QQ-B-654, Grade
V, brazing alloy where tubing or fitting or both tubing and fitting are stainless steel.
MINIMUM WALL THICKNESS FOR STAINLESS STEEL TUBING
Size (mm O.D.) Thickness (mm)
10 1.47
15 2.11
16 2.41
20 3.05
MINIMUM WALL THICKNESS FOR STAINLESS STEEL TUBING
Size (Inches O.D.) Thickness (Inches)
3/8 .058
1/2 .083
5/8 .095
3/4 .120
c. Copper-nickel tube: MIL-T-16420, Composition 70-30, temper-annealed, Type I - seamless,
Class 3300 (22,750 kPa (gage)3300 psig working pressure), Grade 2 (material with heat identification).
Fittings, Brazing: bronze or copper-nickel, silver brazed ends, rated for not less than 20,682
kPa 3000 psi working pressure. Limit brazed joints to required connections to existing piping.
Use welded joints for new and existing piping to the maximum extent practical. Fittings, welding,
40 mm 1 1/2 inches IPS and smaller: ASME B16.11, MIL-C-15726, forged copper-nickel, socket
welding, except that body wall thickness shall not be less than the minimum wall thickness for
the size listed in MIL-T-16420 for Class 3300, and the average socket wall thickness shall be
1.25 times, and the minimum socket wall 1.09 times the minimum wall thickness for that size
listed in MIL-T-16420 for Class 3300; however, for 6 mm 1/4 inch IPS, ASME B16.11, Class 3000
dimensions may be used when approved by the Contracting Officer. Fittings, welding, 50 to 80
mm 2 to 3 inches IPS: ASME B16.9, butt welding, seamless wrought 70-30 copper-nickel, with minimum
wall thickness as listed for that size in MIL-T-16420 for Class 3300.
2.9.3 Globe and Angle Valves
MIL-V-24109, bronze body.
2.9.4 Needle Valves
MIL-V-24109, bronze body, except provide needle valve cartridges in lieu of shutoff valve cartridges.
2.9.5 Safety Valves
ASME BPVC SEC VIII D1 and ASME BPVC SEC IX Code stamped safety valve, [Type [304L] [316L] stainless steel,] [70-30
copper-nickel,] [70-30 nickel-copper,] [bronze,] [carbon steel,] with 0-ring seal union thread piece ends as
provided for MIL-V-24109 valves; factory set and sealed.
2.9.6 Pressure Reducing Valves
NFLPA T3.12.3 R2, nominal pressure rating of [2758] [10,341] [20,680] [41,364] kPa (gage) [400] [1500] [3000]
[6000] psig, body of [stainless steel,] [bronze,] [aluminum bronze,] [naval brass,] outlet pressure and capacity
as indicated, shock and vibration test not required, allowance lists not required.
2.9.7 Adapters
Provide suitable tailpiece adapters for installation of valves conforming to MIL-V-24109 and for other components
with similar union end connections. Tailpieces shall match pipe material: [Type 304L or 316L stainless steel,]
[70-30 nickel-copper,] [70-30 copper-nickel,] socket welding type for 40 mm 1 1/2 inches IPS and smaller. Tailpieces
for tubing: [brazed O.D. type suitable for 20,682 kPa 3000 psi]. Provide thread piece adapters for O-ring union
installation of components made of material different from pipe or where welded joint installation is not suitable.
2.9.8 Pressure Gages (High Pressure)
Pressure gages for high pressure systems shall conform to ASME B40.100, for air, with a scale approximately twice
the system working pressure, nonshatterable safety glass, and pressure blowout back to prevent glass from flying
out in case of an explosion. Gages: [90] [114] mm [3 1/2] [4 1/2] inches in diameter with a steel case and
tubing and an accuracy of one percent full scale in middle half section of scale and 1 1/2 percent of full scale
value in first and last 1/4 sections of scale. Do not fasten bourdon tube pressure-sensitive elements with low-melting-point
solder. Print on gage faces in red letters "USE NO OIL." Provide pressure snubbers or equalizer in pressure
gage installations on inflow side of a gage valve. Mount gage branches vertically on top of an air line to avoid
branch flow of condensate and dirt. Connect a gage to an air line or component through an equalizer, gage valve
(slow-opening needle type), and branch with provision for bleed-off.
2.9.9 Snubbers (or Equalizers)
[Type 304L or Type 316L stainless steel] [70-30 copper-nickel] [70-30 nickel-copper] body with a rated working
pressure not less than system design pressure. Snubber element: sintered stainless steel or other approved
type.
2.9.10 Timed Solenoid Drain
Packaged solenoid drain with 6 mm, [20,682] [34,470] kPa (gage) 1/4 inch, [3000] [5000] psig, direct acting,
normally closed solenoid valve, solid state timer, drain cycle adjustable from zero to 50 minutes, valve open
duration adjustable from one to 14 seconds, power on light, valve open light, operation on 115 or 230 VAC, and
housed in NEMA [1] [_____] enclosure.
2.9.11 Compressed Air Filters
Provide high pressure compressed air filter, single cartridge type, designed for operating pressures not less
than the system design pressure. Filter housing of [Type [304L] [316L] stainless steel] [70-30 copper-nickel]
[70-30 nickel-copper] construction. Provide a cellulose cartridge filter of graded density construction capable
of removing liquids and solids of 5 microns and larger. Provide filter with a bottom drain and [manual drain
valve] [timed solenoid drain].
2.9.12 Strainers
Y-pattern type with [cast stainless steel body, ASTM A 351/A 351M CF8M (Type 316), CF8 (Type 304), CF3 (Type
304L) or CF3M (Type 316L,] [70-30 copper-nickel,] [70-30 nickel-copper,] [forged alloy steel body ASTM A 182/A 182M
, Grade F-22,] rated for the system design working pressure, with 20-mesh Monel or stainless steel screen. Net
strainer area not less then 2.5 times the inlet connection area.
2.9.13 Unions
O-ring seal type compatible with union ends of MIL-V-24109 valves, material and end preparation compatible with
pipe and fittings.
2.9.14 O-Ring Gaskets
SAE AMS7276.
2.9.15 Hangers and Supports
Provide pipe hangers and supports conforming to MSS SP-58, MSS SP-69, and ASME B31.1, except as specified or
indicated otherwise. Hangers for high pressure air lines shall be rigid or braced and sufficiently strong to
prevent "whipping" of a pipe if a break occurs while the line is under pressure. Furnish zinc plated pipe hangers
and supports except for copper plated inserts for copper piping. Provide tubing supports of U-shaped steel bolts
and nuts firmly secured to adequately support structures such as walls, columns, floors, or brackets. Clips
shall fit closely around piping but shall have sufficient clearance to permit longitudinal movement of piping
during normal expansion and contraction. Provide supports at valves, fittings, branch lines, outlets, changes
in direction, equipment, and accessories.
2.10 MEDIUM PRESSURE COMPRESSED AIR PIPING AND ACCESSORIES
NOTE: Components are listed based on operation at maximum temperature of 66
degrees C 150 degrees F. Class 300 steam rated components have water-oil-gas
(WOG) ratings above 2758 kPa (gage) at 66 degrees C 400 psig at 150 degrees
F. If higher operating temperatures are expected, change component descriptions
to higher ratings as required after reviewing appropriate component specification.
Medium pressure compressed air piping and accessories 869 to 2751 kPa (gage) at 66 degrees C 126 to 399 psig
at 150 degrees F shall conform to the following:
2.10.1 Pipe
ASTM A 53/A 53M or ASTM A 106/A 106M, seamless carbon steel, Schedule 40, black.
2.10.2 Fittings, Size 50 Millimeters 2 Inches and Larger
ASME B16.9, carbon steel, butt welding, Schedule 40, or ASME B46.1, carbon steel welding neck flanges, Class
300, ASME B46.1, flanged fittings, carbon steel, Class 300, gaskets ASME B16.20, spiral wound metallic, Class
300, bolts ASTM A 193/A 193M, Grade B7, and nuts, ASTM A 194/A 194M, Grade 7. Butt welded joints shall be full
penetration consumable insert or backing ring type.
2.10.3 Fittings, Size 40 Millimeters 1 1/2 Inches and Smaller
ASME B16.11, forged carbon steel, Class 3000 socket welding or Class 2000 threaded. Seal weld threaded joints
not required to disassemble piping for maintenance. Joints may also be butt welded or flanged, as specified
for sizes 50 mm 2 inches and larger.
2.10.4 Flat-faced Steel Flanges
Where connections are made to Class 250 cast iron flanges with steel flanges, use only flat-faced Class 300 steel
flanges.
2.10.5 Unions
ASME B16.39, Class 2 (3447 kPa (gage)500 psig WOG, cold, non-shock).
2.10.6 Valves
2.10.6.1 Globe and Angle Valves
Sizes 50 mm 2 inches and smaller, bronze, MSS SP-80, Type 3 (Metallic Disc, Renewable Seat), Class 300, threaded
ends, or carbon steel, ASME B16.34, Class 300, threaded ends. Sizes larger than 50 mm 2 inches, ASME B16.34,
carbon steel, tapered disk, Class 300, flanged ends.
2.10.6.2 Check Valves
ASME B16.34 or MSS SP-71, Class 300, steel, lift or swing type.
2.10.6.3 Pressure Reducing Valves
NFLPA T3.12.3 R2, with nominal pressure rating of not less than inlet system pressure indicated. Provide pressure
reducing valves capable of being adjusted to specified flow and pressure, and suitable for intended service.
Provide pilot valve for dome loaded type if required for proper operation.
2.10.6.4 Safety Valves
ASME BPVC SEC VIII D1 and ASME BPVC SEC IX, Code stamped safety valve, bronze body with bronze trim, for unfired
pressure vessels, threaded or flanged connection; factory set and sealed.
2.10.7 Pressure Gages
ASME B40.100, Accuracy Grade A, for air, with steel or brass case, and nonshatterable safety glass, and a pressure
blowout back to prevent glass from flying out in case of an explosion. Gages shall have a 90 mm 3 1/2 inch minimum
diameter dial and a dial range of approximately twice working pressure.
2.10.8 Pipe Hangers and Supports
MSS SP-58, MSS SP-69, and ASME B31.1, except as specified or indicated otherwise. Provide zinc plated pipe hangers
and supports. Provide tubing supports of U-shaped steel bolts and nuts firmly secured to adequately support
structures such as walls, columns, floors, or brackets. Clips shall fit closely around piping but shall have
sufficient clearance to permit longitudinal movement of piping during normal expansion and contraction. Provide
supports at valves, fittings, branch lines, outlets, changes in direction, equipment, and accessories.
2.10.9 Strainers
FS WW-S-2739, Class 250, Style Y, simplex type, with 20-mesh Monel or stainless steel screen.
2.10.10 Traps
FS A-A-60001, to drain water and other liquids from system. Type of traps, as indicated, and rated working pressure
not less than system operating pressure.
2.10.11 Flexible Connections
Vibration isolation, wire braid reinforced corrugated metal hose type, line-sized, with bronze end connections,
suitable for pressure indicated. Length as recommended by manufacturer but not less than [457] [_____] mm [18]
[_____] inches.
2.10.12 Tetrafluoroethylene Tape
FS A-A-58092 for screw-jointed pipe.
2.11 SLEEVES
2.11.1 Floor Slabs, Roof Slabs, and Outside Walls Above and Below Grade
Galvanized-steel pipe having an inside diameter at least 15 mm 1/2 inch larger than the outside diameter of the
pipe passing through it. Provide sufficient sleeve length to extend completely through floors, roofs, and walls,
so that sleeve ends are flush with finished surfaces except that ends of sleeves for floor slabs shall extend
15 mm 1/2 inch above finished floor surface. Sleeves located in waterproofed construction shall include flange
and clamping ring.
2.11.2 Partitions
Galvanized sheet steel, 26 gage or heavier, of sufficient length to completely extend through partition thickness
with sleeve ends flush with partition finished surface.
2.12 VALVE BOX
Provide rectangular concrete design with words "Compressed Air" cast or otherwise marked on the cover. Size
shall be large enough for removal of valve without removing box. Provide valve box for areas as follows:
a. Roads and traffic areas: Heavy Duty, cast iron cover
b. Other areas: Standard duty, heavy steel plate or concrete cover
2.13 IDENTIFICATION LABELS FOR PIPING
Labels for pipes 20 mm 3/4 inch O.D. and larger shall bear printed legends to identify contents of pipes and
arrows to show direction of flow. Except that of pipes smaller than 20 mm 3/4 inch O.D., labels shall have color
coded backgrounds to signify levels of hazard in accordance with PFI ES 22. Legends and type and size or characters
shall also conform to PFI ES 22. Labels shall be made of plastic sheet in conformance with FS A-A-1689 with
pressure-sensitive adhesive suitable for the intended applications or they may be premolded of plastic to fit
over specific pipe outside diameters 20 mm 3/4 inch and larger. For pipes smaller than 20 mm 3/4 inch O.D.,
furnish brass identification tags 40 mm 1 1/2 inches in diameter with legends in depressed black-filled characters.
2.14 BURIED UTILITY WARNING AND IDENTIFICATION TAPE
Polyethylene plastic tape manufactured specifically for warning and identification of buried utility lines.
Tape shall be of the type provided in rolls, 152 mm 6 inches minimum width, color codes for compressed air (gray)
with warning and identification imprinted in bold black letters continuously and repeatedly over entire tape
length. Warning and identification shall be "CAUTION BURIED COMPRESSED AIR LINE BELOW" or similar wording.
Code and letter coloring shall be permanent, unaffected by moisture and other substances contained in trench
backfill material.
2.15 FRESH WATER
Fresh water for cleaning, flushing, and testing shall be clean and potable.
2.16 BASIC PIPING AND COMPONENT MATERIALS
Conform to the following where material is specified by generic type and no specification is listed.
2.16.1 Stainless Steel
Austenitic type, annealed, ASTM A 182/A 182M.
2.16.2 Nickel-Copper
70-30 nickel-copper, annealed, ASTM B 164, alloy N04400, ASTM B 127.
2.16.3 Copper-Nickel
70-30 copper-nickel, soft temper, MIL-C-15726.
2.16.4 Other Materials
For materials where no specification is listed above, conform to material specifications listed in ASME B31.1
or ASME BPVC SEC VIII D1.
2.17 SOURCE QUALITY CONTROL
Test air compressors and compressed air dryers at the factory to assure proper operation. Certify satisfactory
accomplishment of tests.
PART 3 EXECUTION
3.1 INSTALLATION
Install materials and equipment as indicated and in accordance with manufacturer's recommendations.
3.1.1 Excavation and Backfilling
Section 31 00 00 EARTHWORK.
3.1.2 Corrosion Protection
Provide corrosion protection for buried steel [and corrosion resistant steel] piping in accordance with Section
09 97 13.28 PROTECTION OF BURIED STEEL PIPING AND STEEL BULKHEAD TIE RODS.
3.1.3 Piping
Provide Non-Destructive Examination (NDE) report for welding of piping. Unless specifically stated to the contrary,
fabrication, assembly, welding, and brazing shall conform to ASME B31.1 for all piping of the air system. Piping
shall follow the general arrangement shown. Cut piping accurately to measurements established for the work.
Work piping into place without springing or forcing, except where cold-springing is specified. Piping and equipment
within buildings shall be entirely out of the way of lighting fixtures and doors, windows, and other openings.
Locate overhead piping in buildings in the most inconspicuous positions. Do not bury or conceal piping until
it has been inspected, tested, and approved. Where pipe passes through building structure, pipe joints shall
not be concealed, but shall be located where they may be readily inspected and building structure shall not be
weakened. Avoid interference with other piping, conduit, or equipment. Except where specifically shown otherwise,
vertical piping shall run plumb and straight and parallel to walls. Piping connected to equipment shall be installed
to provide flexibility for vibration. Adequately support and anchor piping so that strain from weight of piping
is not imposed on the equipment.
3.1.3.1 Fittings
NOTE: Delete bending of medium or high pressure pipe when not included in project.
Use long radius ells where appropriate to reduce pressure drops. Pipe bends in lieu of fittings may be used
for piping where space permits. Pipe bends shall have a uniform radius of at least five times the pipe diameter
and must be free from any appreciable flattening, wrinkling, or thinning of the pipe. Mitering of pipe to form
elbows, notching straight runs to form full sized tees, or any similar construction shall not be used. Make
branch connections with welding tees, except factory made forged welding branch outlets or nozzles having integral
reinforcements conforming to ASME B31.1 may be used.
a. Bending of High Pressure Pipe: Prior to bending pipe for high pressure systems, the Contractor
shall submit for approval written fabrication and inspection procedures and calculations showing
the required minimum wall thickness of pipe after bending. Only cold bending shall be permitted.
The fabrication procedure shall indicate the required pipe wall thickness prior to bending,
equipment to be used, set up and bending procedures, and inspection and acceptance criteria.
Inspection shall include verification of minimum wall thickness by ultrasonic or other methods
if deemed necessary by the Contracting Officer. No wrinkles or other contour irregularities
will be permitted in the bent pipe. Check flattening in accordance with ASME B31.1. Include
required dimensional checks in inspection procedures and acceptable values tabulated for each
pipe size to be bent. Qualified personnel shall perform nondestructive examinations required
in accordance with qualified procedures.
3.1.3.2 Clearances for Welding
Provide clearances from walls, ceilings, and floors to permit the installation of joints. The clearances shall
be at least 150 mm 6 inches for pipe sizes 100 mm 4 inches and less, 250 mm 10 inches for pipe sizes over 100
mm 4 inches, and sufficient in corners. However, the specified clearances shall not waive requirements for welders
to be qualified for the positions to be welded.
3.1.3.3 Cleaning
NOTE: Special cleaning requirements are mainly intended for high pressure systems.
Special cleaning should also be considered for medium pressure systems over
1724 kPa (gage) 250 psig which may be subject to dieseling explosions when oil
contamination is present. Objective cleaning standards are specified to simplify
inspection and acceptance in the field.
Before jointing and erection of piping or tubing, thoroughly clean interiors of pipe sections, tube, and components.
In steel pipe, loosen scale and other foreign matter by rapping sharply and expel by wire brush and swab. Blow
out both steel pipe and copper tube and components with compressed air at 690 kPa (gage) 100 psig or more. Maintain
cleanliness by closure of pipe/tube openings with caps or plugs. Before making final terminal connections, blow
out complete system with compressed air at 690 kPa (gage) 100 psig or more. Cleaning and cleanness of medium
pressure systems over 1724 kPa (gage) 250 psig and high pressure systems shall conform to the paragraph entitled
"Cleaning and Cleanness Requirements."
3.1.3.4 Changes in Pipe Size
Use reducing fittings for changes in pipe size. The use of bushings will not be permitted. In horizontal lines,
65 mm 2 1/2 inches and larger, reducing fittings shall be of the eccentric type to maintain the bottom of the
lines in the same plane.
3.1.3.5 Drainage and Flexibility
Compressed air piping shall be free of unnecessary pockets and pitched approximately one mm per 400 mm 3 inches
per 100 feet in the direction of flow to low points. Where pipes must be sloped so that condensate flows in
opposite direction to air flow, slope one mm per 200 mm 6 inches per 100 feet or greater. Provide flexibility
by use of fittings, loops, and offsets in piping. Install branches at top of a main to prevent carryover of
condensate and foreign matter.
3.1.4 Threaded Joints
Where possible use pipe with factory cut threads, otherwise cut pipe ends square, remove fins and burrs, and
cut taper pipe threads in accordance with ASME B1.20.1. Threads shall be smooth, clean, and full cut. Apply
thread tape to male threads only. Work piping into place without springing or springing or forcing. Backing
off to permit alignment of threaded joints will not be permitted. Engage threads so that not more than three
threads remain exposed.
3.1.5 Flanged Joints in High Pressure System
Install using calibrated torque wrenches or feeler gage methods to assure proper gasket compression. Calibrate
torque wrench immediately prior to use.
3.1.6 Welding and Brazing
Perform welding and brazing in accordance with qualified procedures using qualified welders and welding operators
and brazers. Do not perform welding and brazing when the quality of the completed weld or braze could be impaired
by the prevailing working or weather conditions. The Contracting Officer will determine when weather or working
conditions are unsuitable for welding. Welding of hangers, supports, and plates to structural members shall
be in accordance with AWS D1.1/D1.1M. Mark welding and brazing detail drawings to identify the welder or brazer
making the joint.
3.1.6.1 Cleaning for Welding and Brazing
Surfaces to be welded or brazed shall be free from loose scale, slag, rust, paint, oil, and other foreign material.
Joint surfaces shall be smooth and free from defects which might affect proper welding. Clean each layer of
weld metal thoroughly by wire brushing, grinding, or chipping prior to inspection or deposition of additional
weld metal. Conform to paragraph entitled "Cleaning and Cleanness Requirements" [for medium pressure systems
over 1724 kPa (gage) 250 psig] [and] [for high pressure] systems.
3.1.6.2 Stress Cracking During Brazing
For austenitic stainless steel and other material susceptible to stress corrosion cracking from molten brazing
filler metal, avoid applying stress during brazing.
3.1.6.3 Welding or Brazing of Valves
Welding or Brazing of Valves: Disassemble valves subject to damage from heat during welding or brazing and reassemble
after installation. Open valves two or three turns off the seat when not subject to heat damage during welding
or brazing; do not backseat valve.
3.1.7 Valves
Install valves in conformance with ASME B31.1 at the locations indicated and elsewhere as required for the proper
functioning of the system.
3.1.7.1 Globe Valves
Install globe valves so that the pressure will be below the disk. Install globe valves with the stems vertical.
3.1.7.2 Pressure-Reducing Valves
Provide compressed air entering each pressure-reducing valve with a strainer. Provide each pressure-reducing
valve unit with two block valves and with a globe or angle bypass valve and bypass pipe. Provide a bypass around
a reducing valve of reduced size to restrict its capacity to approximately that of the reducing valve. Provide
each pressure reducing valve unit with an indicating gage to show the reduced pressure, and a safety valve on
the lower pressure side. These requirements do not apply to small pressure regulating valves used to adjust
pressure for pneumatic equipment.
3.1.8 Hangers and Supports
NOTE: See USACE TI 809-04 "Seismic Design for Essential Buildings" (for new
designs) or TI 809-05 "Seismic Design for Existing Buildings" (for renovations),
for calculating pipe support spacing for schedules not shown. Also, space supports
for high pressure air piping to provide restraint against whipping and damage
to other piping if the high pressure line breaks; see DM 3.5, "Compressed Air
and Vacuum Systems," Section 7, "Piping Systems." Delete Table I and reference
to seismic requirements if not required.
Selection, fabrication and installation of piping hangers and supports shall conform to MSS SP-58, MSS SP-69,
and MSS SP-89 [except that spacing of the hangers and supports shall be as per Table I.] [Provide seismic restraints
for piping in accordance with SMACNA 1650.]
TABLE I. MAXIMUM SPAN FOR PIPE
__________________________________________________________________________
STD. WT. EX. STRONG
DIAMETER STEEL PIPE STEEL PIPE
MM SCHEDULE 40 SCHEDULE 80
15 1.52 1.52
__________________________________________________________________________
20 1.75 1.75
__________________________________________________________________________
25 1.98 1.98
__________________________________________________________________________
40 2.29 2.36
__________________________________________________________________________
50 2.59 2.59
__________________________________________________________________________
65 2.82 2.90
__________________________________________________________________________
80 3.125 3.20
__________________________________________________________________________
90 3.35 3.35
__________________________________________________________________________
100 3.51 3.58
__________________________________________________________________________
125 3.89 3.96
__________________________________________________________________________
150 4.19 4.27
__________________________________________________________________________
200 4.73 4.88
__________________________________________________________________________
250 5.18 5.34
__________________________________________________________________________
300 5.56 5.79
__________________________________________________________________________
TABLE I. MAXIMUM SPAN FOR PIPE
__________________________________________________________________________
STD. WT. EX. STRONG
DIAMETER STEEL PIPE STEEL PIPE
INCHES SCHEDULE 40 SCHEDULE 80
1/2 5'-0" 5'-0"
__________________________________________________________________________
3/4 5'-9" 5'-9"
__________________________________________________________________________
1 6'-6" 6'-6"
__________________________________________________________________________
1 1/2 7'-6" 7'-9"
__________________________________________________________________________
2 8'-6" 8'-6"
__________________________________________________________________________
2 1/2 9'-3" 9'-6"
__________________________________________________________________________
3 10'-3" 10'-6"
__________________________________________________________________________
3 1/2 11'-0" 11'-0"
__________________________________________________________________________
4 11'-6" 11'-9"
__________________________________________________________________________
5 12'-9" 13'-0"
__________________________________________________________________________
6 13'-9" 14'-0"
__________________________________________________________________________
8 15'-6" 16'-0"
__________________________________________________________________________
10 17'-0" 17'-6"
__________________________________________________________________________
12 18'-3" 19'-0"
__________________________________________________________________________
3.1.9 Pressure Gages
Provide pressure guages with a shut-off valve or petcock installed between the gage and the line.
3.1.10 Strainers
Provide strainers with meshes suitable for the services where indicated, or where dirt might interfere with the
proper operation of valve parts, orifices, or moving parts of equipment.
3.1.11 Equipment Foundations
Provide equipment foundations of sufficient size and weight and of proper design to preclude shifting of equipment
under operating conditions or under any abnormal conditions which could be imposed upon the equipment. Provide
foundations which meet the requirements of the equipment manufacturer, and when required by the Contracting Officer,
obtain from the equipment manufacturer approval of the foundation design and construction for the equipment involved.
Equipment vibration shall be maintained within acceptable limits, and shall be suitably dampened and isolated.
3.1.12 Equipment Installation
Install equipment strictly in accordance with these specifications, and the manufacturers' installation instructions.
Grout equipment mounted on concrete foundations before piping is installed. Install piping in a manner that
does not place a strain on any of the equipment. Do not bolt flanged joints tight unless they match properly.
Extend expansion bends adequately before installation. Grade, anchor, guide and support piping without low pockets.
3.1.13 Cleaning of System
NOTE: Special cleaning requirements are mainly intended for high pressure systems.
Special cleaning should also be considered for medium pressure systems over
1724 kPa (gage) 250 psig which may be subject to dieseling explosions when oil
contamination is present. Objective cleaning standards are specified to simplify
inspection and acceptance in the field.
Clean the various system components before final closing as the installations are completed. Remove foreign
matter from equipment and surrounding areas. [Cleaning and cleanliness shall conform to paragraph entitled "Cleaning
and Cleanliness Requirements" for pressures over 1724 kPa (gage) 250 psig.] Preliminary or final tests will
not be permitted until the cleaning is approved by the Contracting Officer.
3.1.14 Pipe Sleeves
Provide pipe sleeves where pipes and tubing pass through masonry or concrete walls, floors, roofs, and partitions.
Hold sleeves securely in proper position and location before and during construction. All sleeves shall be of
sufficient length to pass through entire thickness of walls, partitions, or slabs. Extend sleeves in floor slabs
50 mm 2 inches above the finished floor. Pack space between the pipe or tubing and the sleeve firmly with oakum
and caulk both ends of the sleeve with elastic cement.
3.1.15 Floor, Wall, and Ceiling Plates
Provide chromium-plated steel or nickel-plated cast iron plates on pipes passing through floors and partitions
of finished rooms. Provide painted cast-iron, malleable iron, or steel for other areas.
3.1.16 Flashing for Buildings
Provide flashing [as required] [in accordance with Section 07 57 13 FLASHING AND SHEET METAL] where pipes pass
through building roofs and outside walls.
3.1.17 Unions and Flanges
Provide unions and flanges where necessary to permit easy disconnection of piping and apparatus, and as indicated.
Provide a union for each connection having a screwed-end valve. [Provide unions or flanges not farther apart
than 30 meters 100 feet.] [Provide unions or flanges as indicated.] Provide unions on piping under 50 mm 2
inches in diameter, and provide flanges on piping 50 mm 2 inches and over in diameter. Install dielectric unions
or flanges between ferrous and non-ferrous piping, equipment, and fittings; except that bronze valves and fittings
may be used without dielectric couplings for ferrous-to-ferrous or non-ferrous to non-ferrous connections.
3.1.18 Painting of Piping and Equipment
Paint piping and equipment in accordance with Section 09 90 00 PAINTS AND COATINGS.
3.1.19 Identification of Piping
Identify piping in accordance with PFI ES 22. Use commercially manufactured piping identification labels. Space
identification marking on runs not farther apart than 15 meters 50 feet. Provide two copies of the piping identification
code framed under glass and install where directed.
3.1.20 Warning and Identification Tape
Coordinate installation of utility warning and identification tape with backfill operation. Provide tape above
buried lines at a depth of 200 to 305 mm 8 to 12 inches below finish grade.
3.2 CLEANING AND CLEANNESS REQUIREMENTS
NOTE: Special cleaning requirements are mainly intended for high pressure systems.
Special cleaning should also be considered for medium pressure systems over
1724 kPa (gage) 250 psig which may be subject to dieseling explosions when oil
contamination is present. Objective cleaning standards are specified to simplify
inspection and acceptance in the field.
Cleaning and cleanness requirements shall conform to ASTM A 380 and the following.
3.2.1 Substitution
The word "shall" shall be substituted for "should" in ASTM A 380.
3.2.2 Prohibited Methods and Processes
The following methods and processes shall not be used.
a. Chemical descaling (acid pickling).
b. Abrasive blasting and vapor blasting.
c. Alkaline cleaning.
d. Emulsion cleaning.
e. Chelate cleaning.
f. Acid cleaning
g. Passivation.
h. Corrosion inhibitors shall not be used.
3.2.3 Approval of Methods and Procedures
Prepare and submit written cleaning procedures for approval. Perform production cleaning in accordance with
approved procedures.
3.2.4 Tools Used on Corrosion-Resistant Alloys
Tools used on corrosion-resistant alloys such as grinding, polishing, filing, deburring, and brushing tools shall
be visually clean and shall not have been used on carbon or low alloy steels, aluminum, lead or materials containing
lead or lead components, or other low melting point materials. Wire brushes shall be 300 series stainless steel.
Unless otherwise approved, each tool shall be used on only one type of corrosion-resistant metal.
3.2.5 Cleaning Before Installation
Clean piping, components, and equipment before installation.
3.2.6 Cleaning Requirements
Clean surfaces containing no crevices or inaccessible areas by any of the procedures described herein. Clean
surfaces containing crevices by immersion in unused or redistilled acetone, ethanol, or isopropanol only.
3.2.6.1 Vapor Degreasing
Vapor degreasing may be used on surfaces containing no crevices or inaccessible areas and shall be accomplished
by the following procedures:
a. Dry all parts entering degreaser.
b. Load parts onto racks in the condensing zone so that they do not touch each other, and in
such a manner to insure complete draining of solvents.
c. Use perchloroethylene bath. Maintain bath at 121 to 127 degrees C 250 to 260 degrees F
. The bath shall contain a neutral inhibitor to prevent acid formation due to hydrolysis.
Other types of inhibitors are not permitted.
d. Change solvent when boiling point of perchloroethylene exceeds 127 degrees C 260 degrees
F. Dump solvent earlier if cleanliness standards are not attained.
e. Lower or raise parts in the degreaser at a rate not to exceed 5 mm/s 12 inches per minute
and immerse in vapor phase. Spray with clean solvent during immersion time. Keep the spray
nozzle at least 305 mm one foot below the vapor line during spraying. Allow part to remain
in vapor until condensation ceases (3 to 5 minutes). Dry parts completely before removing from
degreaser.
3.2.6.2 Degreasing by Immersion or Wiping
Degreasing of parts having no inaccessible areas or crevices may be performed by immersion in solvent or by wiping
with a clean lintless wiping cloth saturated with the solvent perchloroethylene, unused or redistilled acetone,
ethanol, or isopropanol, or Stoddard solvent for preliminary degreasing. Dry in accordance with paragraph entitled
"Drying Requirements."
3.2.6.3 Trisodium-Phosphate Detergent Cleaning (Degreasing)
Trisodium-phosphate detergent cleaning may be used on surfaces containing no crevices or inaccessible areas and
shall be accomplished as follows:
a. Remove heavy dirt by either scrubbing with a non-shedding bristle brush using a solution
of up to 112.2 mL one fluid ounce of nonionic detergent per liter gallon of tap water or immersing
the parts in a hot (approximately 71 - 88 degrees C 160 - 190 degrees F) solution consisting
of 207 to 296 mL 7 to 10 ounces of trisodium phosphate and up to 112.2 mL one fluid ounce of
the nonionic detergent per liter gallon of tap water for about 20 minutes. Agitate and use
brush as necessary.
b. Rinse parts thoroughly in hot water at a minimum of 49 degrees C 120 degree F.
c. Dry the parts in accordance with paragraph entitled "Drying Requirements."
3.2.6.4 Ultrasonic Cleaning
Cleaning methods using ultrasonic equipment may be used.
3.2.7 Drying Requirements
Accomplish drying by still or forced clean air or inert gas, drying oven, or by evacuation. When using evacuation,
exercise care to prevent evacuating-pump lubricant from entering the equipment. Check compressed air used for
drying to ensure cleanliness by blowing through a clean, white, cotton filter cloth for about 5 minutes at full
drying velocity.
3.2.8 Inspection and Acceptance Criteria for Cleanliness
Conform to ASTM A 380 and the following:
3.2.8.1 Cleanness Criteria
All surfaces of piping material, equipment, instruments, and other components which will come in contact with
compressed air shall be clean to the extent that no contamination is visible to a person with normal visual acuity
(natural or corrected) under a lighting level of at least 1076 lux 100 footcandles on the surface being inspected.
Cleanness of surface which cannot be visually inspected due to inaccessibility or geometry shall be determined
by an interpretation of the discoloration or dirt obtained by wiping with a clean, white, wet or dry cloth.
Free of contamination shall mean free of oil, dirt, metallic flakes, preservatives, paint, and any other substances
which may present a safety hazard or impair the quality of the compressed air.
3.2.8.2 Critical Surfaces
No rust shall be allowed on valve seats, orifice plates or other critical surfaces. Thin films of rust are acceptable
on other corrosion-resistant material surfaces provided there is no visible thickness or evidence of pitting
and the total area involved does not exceed one percent of the total surface area of the component in contact
with compressed air.
3.2.8.3 Carbon and Low Alloy Steels
A uniform light rust that can be removed by brushing or wiping is acceptable.
3.2.9 Maintaining Cleanness During Installation
Maintain cleanness of piping, components, and equipment during installation. Dirt and debris producing operations
shall be performed so that dirt and debris fall away from system openings; otherwise, provide covers over openings
to preclude contamination. Cap, plug, cover, or bag openings and pipe ends and secure with tape when they are
not required to be open for the performance of work. Metal caps, plugs, and covers shall be austenitic stainless
steel. Plastic items and tape shall be free of substances that can have a harmful effect on stainless steel
and other corrosion-resistant metals in the system.
3.2.10 Cleanness Verification Flushes
After installation, check the systems for cleanness by flushing with water. Perform flushing so that the minimum
velocity through any part of the system is not less than [1.1] [_____] meters [3.6] [_____] feet per second.
Pass flush water through a filter for cleanness evaluation. Filter element shall be corrosion-resistant wire
cloth with mesh size conforming to ASTM E 11, No. 20 (850 micrometers), No. 25 (710 micrometers), or No. 30 (600
micrometers). Filter area shall be sufficient to limit pressure drop so that required flushing velocity can
be attained.
3.2.10.1 Flush Acceptance Criteria
NOTE: Select flush acceptance criteria based on how critical the system is
and the volume of system to be flushed. More particles may be expected and
may be acceptable in larger systems.
The system shall be flushed until there is no more than [slight speckling] [[0.1] [0.5] [_____] cubic centimeters]
of particulates on the filter screen. There shall be no particles larger than 0.79 by 1.59 mm 1/32 by 1/16 inch
long. The flush water shall show no visual evidence of contamination such as oil particles, discoloration,
or iridescent surface film characteristic of oil.
3.2.10.2 Recleaning of Systems
Systems which fail to meet acceptance flush criteria after flushing for more than 4 hours shall be recleaned
by the Contractor at no additional cost to the Government. Prepare recleaning procedures and submit to the Contracting
Officer for approval. Remove instruments, components, and any other items that may be damaged by recleaning.
Perform recleaning by flushing with hot water at not less than 60 degrees C 140 degrees F.
3.3 CLEANING SILVERBRAZED PIPING
NOTE: All silverbrazed piping, including low pressure systems, should be cleaned
to preclude corrosion from residual brazing flux.
Clean silverbrazed piping to remove residual flux remaining in the system after fabrication. Use one of the
procedures below. The hot flush and hot recirculating flush are preferred. Minimum flow rate through any part
of the system in liters gallons per second minute shall be 0.0037 1.5 times the inside diameter of the pipe in
mm inches. For any flushing method used, the system shall be full of water so that joints are completely submerged
at all times.
3.3.1 Hot Flushing Method
Hot flush the system for one hour using heated fresh water. No part of the system shall go below 43 degrees
C 110 degrees F.
3.3.2 Hot Recirculating Flush Method
Perform hot recirculating flush for one hour. Heat water during flushing so that no part of the system falls
below 43 degrees C 110 degrees F. After completing the hot recirculating flush, flush the system with cold fresh
water for 15 minutes.
3.3.3 Cold Soak Method
Cold soak the system using fresh water at not less than 15.50 degrees C 60 degrees F for 12 hours. Following
the 12 hour soak, flush the system with fresh water at not less than 15.50 degrees C 60 degrees F for 4 hours.
3.4 FIELD QUALITY CONTROL
3.4.1 Examinations
3.4.1.1 Welding Examinations
NOTE: The paragraphs will be edited and inserted if necessary to ensure proper
implementation of the "CONTRACTOR QUALITY CONTROL PROGRAM." The specification
writer or design engineer must indicate how much quality control of welding
is needed for each project and who is to be responsible, i.e., primarily the
Contractor or the Government. Rarely will a project require 100 percent testing
of welds by NDE methods. The designer must determine the required methods and
the extent of inspection and testing and must indicate the extent in this section
of the project specifications or on the project drawings by notes, nondestructive
test symbols, or other means. Table II at the end of this section was developed
from MIL-STD MIL-STD-278, "Fabrication, Welding and Inspection, and Casting
Inspection and Repair for Machinery, Piping, and Pressure Vessels in Ships of
the United States Navy." The referenced applicable publications and Army Technical
Manual, "WELDING DESIGN, PROCEDURES AND INSPECTION," TM-5-805-7, may be used
for guidance in determining inspection and testing requirements. The specifications
or drawings must clearly indicate which joints require 100 percent NDE inspection,
which joints require random NDE inspection, and which NDE methods are to be
employed for each joint. For random inspection, the drawings must indicate
the location, number of joints, and minimum increment length of weld that will
be subject to NDE inspection without predisclosing the exact spots to be examined.
Joints not indicated to be tested by NDE methods shall be subject to visual
inspection only. In cases where the nature of the welding is such as to require
visual inspection only, the requirements for other nondestructive examinations
should be deleted from these paragraphs and from paragraph entitled "QUALIFICATION
OF INSPECTION AND NONDESTRUCTIVE PERSONNEL."
NOTE: Information based on Table II must be developed and included in each
project specification. Table must clearly define the systems to be inspected
and the type of NDE required. Revise Table II if required for the project.
[The Government will] [The Contractor shall] perform visual and nondestructive examinations to detect surface
and internal discontinuities in completed welds, and submit a Non-Destructive Examination (NDE) report meeting
the requirements specified in ASME B31.1. [The Contractor shall obtain the services of a qualified commercial
inspection or testing laboratory or technical consultant, approved by the Contracting Officer.] Visually examine
welds. Perform [radiographic,] [liquid penetrant,] [or] [magnetic particle] examination as specified in Table
II of this section. For systems operating at 6894 kPa (gage) 1000 psig or higher, all welds shall be examined.
For high pressure systems operating less than 6894 kPa (gage) 1000 psig, perform random NDE. When examination
and testing indicate defects in a weld joint, the weld shall be repaired by a qualified welder. Remove and replace
defects as specified in ASME B31.1, unless otherwise specified. Repair defects discovered between weld passes
before additional weld material is deposited. Whenever a defect is removed, and repair by welding is not required,
blend the affected area into the surrounding surface, eliminating sharp notches, crevices, or corners. After
defect removal is complete and before rewelding, examine the area by the same test methods which first revealed
the defect to ensure that the defect has been eliminated. After rewelding, reexamine the repaired area by the
same test methods originally used for that area. Any indication of a defect shall be regarded as a defect unless
reevaluation by surface conditioning [and NDE] shows that no unacceptable defects are present. The use of any
foreign material to mask, fill in, seal, or disguise welding defects will not be permitted.
3.4.1.2 Brazing Examinations
The Contractor shall perform brazing examinations.
a. Visual Examinations
Visually examine all compressed air systems as follows:
(1) Check brazed joint fit-up. Diametrical clearances shall conform to brazing procedure requirements.
(2) Check base material of pipe and fitting for conformance to the applicable drawing or specification.
(3) Check grade of brazing alloy for conformance to the brazing procedure before fit-up or
brazing.
(4) Check completed brazed joint for a complete ring of brazing alloy between the outside surface
of the pipe and the face of the fitting, and for a visible fillet.
(5) Check stainless steel and other susceptible material for evidence of stress cracks. Check
inside of joint if possible with borescope or other aids.
b. Nondestructive Examination
For high pressure compressed air systems, any fitting, copper-nickel pipe, or stainless steel tubing which is
reused after unsweating a brazed joint shall be liquid penetrant examined for cracks. Any crack detected shall
be cause for rejection of the fitting or pipe. Liquid penetrant examination shall be performed by qualified
personnel.
c. Repair of Brazed Joints
Defective joints may be repaired. However, no more than two attempts to repair by reheating and additional face
feeding of brazing filler metal will be permitted, after which the defective joint shall be unsweated, reprepared
as a new joint, examined for defects on pipe and fittings, and rebrazed. Perform required NDE.
3.4.2 Testing
NOTE: If air (pressure) drop tests are used for system acceptance, assure that
leakages at acceptable rates through valves (or other components) are not causing
pressure drop. Most hard-seated valves have some allowable leakage rate (about
10 cubic centimeters 0.0026 gal per hour of water per 25 mm one inch valve
size or 3 liters per hour 0.1 cubic feet per hourof gas per 25 mm one inch of
valve size). Delete check for cross-connection if only one type of system is
involved in project.
3.4.2.1 General Requirements, Testing
Perform testing after cleaning and acceptance of cleanness. Contractor shall provide everything required for
tests. Tests shall be subject to the approval of the Contracting Officer. Calibrate the test pressure gage with
a dead weight tester within [15] [_____] days before use and certify by initial and date on a sticker applied
to dial face. [Pressurize each piping system individually and check to assure that there are no cross-connections
between different systems prior to hydrostatic and operational tests.]
a. Supervision of Testing
For [high] [and] [medium] pressure system, an experienced registered professional engineer responsible for safety
and employed by the Contractor shall be present during testing.
3.4.2.2 Hydrostatic and Leak Tightness Tests
a. Preliminary Preparation
Remove or isolate from the system the compressor, air dryer, filters, instruments, and equipment which would
be damaged by water during hydrostatic tests and reinstall after successful completion of tests.
b. Performance of Hydrostatic Tests
NOTE: Specify or show on the drawings the design working pressure of each system
in the project.
Hydrostatically test piping systems in accordance with ASME B31.1. Vent or flush air from the piping system.
Pressurize system for 10 minutes with water at one and one-half times design working pressure, then reduce to
design working pressure and check for leaks and weeps.
c. Compressed Air Leak Tightness Test
After satisfactory completion of hydrostatic pressure test, blow systems dry with clean, oil-free compressed
air, and test with clean, dry air at design working pressure. Brush joints with soapy water solution to check
for leaks. Install a calibrated test pressure gage in piping system to observe any loss in pressure. Maintain
required test pressure for a sufficient length of time to enable an inspection of joints and connections.
d. Compressed Air Pressure Test For High Pressure Systems
For high pressure systems, compressed air at system design pressure shall then stand in a system to equalize
temperature. Pressure drop, corrected for temperature change, shall not be more than one percent in 24 hours
for a test pressure 6894 kPa (gage) 1000 psig and above, and not over 5 percent in 6 hours for test pressures
from 2758 to 6894 kPa (gage) 400 to 1000 psig. Use formula below to correct pressure for temperature change.
PF + 101.32 = (PI + 101.32)(TF + 273)/(TI + 273)
PF + 14.7 = (PI + 14.7)(TF + 460)/(TI + 460)
Where PF = Final Pressure, (kPa (gage)) (psig)
PI = Initial Pressure, (kPa (gage)) (psig)
TF = Final Temperature, (degrees C F)
TI = Initial Temperature (degrees C F)
3.4.2.3 Operational Tests
Test equipment as in service to determine compliance with contract requirements and warranty. During the tests,
test equipment under every condition of operation. Test safety controls to demonstrate performance of their
required function. Completely test system for compliance with specifications.
3.5 INSTRUCTION TO GOVERNMENT PERSONNEL
Provide [2] [_____] man-days of instruction to [2] [_____] Government personnel in accordance with Section
23 03 00.00 20 BASIC MECHANICAL MATERIALS AND METHODS for each type of compressor and compressed air dryer in
the project.
TABLE II
HP Piping (2758 kPa (Gage) Higher) Inspection Requirements 1/
Required Nondestructive Examination
---------------------------------------------------------------------------
Welded Joint
type and pipe VISUAL EXAMINATION T/PT TEST RADIOGRAPHY
size, mm Root Completed Root Completed Completed Extent
Layer Weld Layer Weld Weld of
___________________________________________________________________________
Butt 100 and X2/ X X2/ X3/ X 6.28
greater radian
---------------------------------------------------------------------------
Butt 65 to 90 X2/ X X2/ X3/ X4/5/ At least
incl 105 radian
---------------------------------------------------------------------------
Butt less X2/ X X2/ X3/ X4/5/6/ At least
than 65 1.05 radian
---------------------------------------------------------------------------
All socket X2/ X X2/ X -- --
and fillets
---------------------------------------------------------------------------
TABLE II
HP Piping (400 psig and Higher) Inspection Requirements 1/
Required Nondestructive Examination
___________________________________________________________________________
Welded Joint
type and pipe VISUAL EXAMINATION MT/PT TEST RADIOGRAPHY
size, inches Root Completed Root Completed Completed Extent
Layer Weld Layer Weld Weld of
___________________________________________________________________________
Butt 4 and X2/ X X2/ X3/ X 360 degrees
greater
---------------------------------------------------------------------------
Butt 2 1/2 X2/ X X2/ X3/ X4/5/ At least
to 3 1/2 60 degrees
incl.
---------------------------------------------------------------------------
Butt less X2/ X X2/ X3/ X4/5/6/ At least
than 2 1/2 60 degrees
---------------------------------------------------------------------------
All socket X2/ X X2/ X -- --
and fillets
---------------------------------------------------------------------------
Legend: X - Indicates that test is required.
MT Magnetic Particle Inspection
PT Liquid Penetrant Inspection
RT Radiographic Examination
NOTES:
1/ Where new welds in piping intersects existing or older welds, the latter welds shall be inspected for a distance
of 150 mm 6 inches or a distance equal to 50 percent of the pipe size diameter, whichever is less, as measured from
points of intersection. The existing or older weld and adjacent base material shall be free from cracks. Where
non-intersecting adjacent existing welds are inadvertently radiographed, only cracks shall be cause for rejection.
2/ MT/PT inspect the first or root pass of welds and when accessible, the reverse or back-chipped ground, gouged
or machined side prior to depositing metal on the reverse side. Visual examination at 5X magnification may be substituted
for MT/PT inspection. Linear discontinuities shall be unacceptable. Use 5X inspection where crevices cannot be
cleaned thoroughly.
3/ MT/PT test shall be performed only when post-weld heat treatment is required and when specified on drawing.
The test shall be conducted after heat treatment and shall include 6.28 radian 360 degrees of circumferential weld
surface and adjacent base material. Where 6.28 radian 360 degrees RT is performed after heat treatment, MT/PT is
not required, except where specified on drawing.
4/ RT of welds on piping in the horizontal fixed position shall represent a sector which was welded in the vertical
or overhead position.
5/ In lieu of 1.05 radian 60 degree RT, PT or MT may be performed on the inside of a joint where weld is
within 2 1/2 nominal pipe diameters from the open end is back welded, has backing ring removed or used consumable insert.
6/ RT is required where the working pressure exceeds 3964 kPa (gage) 575 psig. For working pressure 3964 kPa
(gage) 575 psig and below, inspection may be performed in lieu of RT.