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USACE / NAVFAC / AFCESA / NASA UFGS-02552 (August 2004)
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NAVFACMasterFormatTM 2004 - 33 63 16
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UFGS-02552N (August 2001)
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated 23 June 2005
Latest change indicated by CHG tags
Section Table of Contents
SECTION 02552
EXTERIOR SHALLOW TRENCH STEAM DISTRIBUTION
08/04
PART 1 GENERAL
1.1 REFERENCES
1.2 SYSTEM DESCRIPTION
1.3 SUBMITTALS
1.4 QUALITY ASSURANCE
1.4.1 Certification of Welder's Qualifications
PART 2 PRODUCTS
2.1 PIPE
2.1.1 [Steam] [Hot Water] Pipe
2.1.2 Condensate Pipe
2.1.3 Buried Steel Piping to Cooling Well or Drain
2.2 FITTINGS
2.2.1 Threaded Fittings
2.2.2 Socket-Welding Fittings
2.2.3 Buttwelding Fittings
2.2.4 Eccentric Reducing Fittings
2.2.5 Flanges and Unions
2.2.6 Gaskets, Bolts, Nuts, and Washers
2.3 VALVES
2.3.1 Valves for [Steam] [Hot Water] Service
2.3.2 Valves for Condensate Service
2.4 PIPING ACCESSORIES
2.4.1 Pipe Hangers and Supports
2.4.2 Strainers
2.4.3 Traps
2.4.4 Gages
2.4.5 Pipe Sleeves
2.4.6 Escutcheon Plates
2.4.7 Electronic Steam Flow Meters
2.4.8 Steam Flow Meters
2.4.9 Guided Slip Tube Expansion Joints
2.4.10 Flexible Ball Expansion Joints
2.4.11 Bellows Expansion Joints
2.5 MANHOLE DRAINERS (EJECTORS)
2.6 CONCRETE MANHOLES
2.7 NAMEPLATES
2.8 SHALLOW CONCRETE TRENCH
PART 3 EXECUTION
3.1 INSTALLATION
3.2 PIPING
3.3 FIELD QUALITY CONTROL
3.3.1 Inspections
3.3.2 Piping Tests
3.4 FIELD PAINTING
3.5 CONNECTIONS TO EXISTING SYSTEMS
SECTION 02552
EXTERIOR SHALLOW TRENCH STEAM DISTRIBUTION
NOTE: This guide specification covers the requirements for
exterior shallow
trench heat distribution systems including concrete trench, manholes, piping,
pipe anchors, pipe supports, interface with each manhole, and the watershed
to aboveground piping.
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).
Use of electronic communication is encouraged.
Brackets are used in the text to indicate designer choices or locations where
text must be supplied by the designer.
NOTE: System design must conform to Unified Facilities Criteria (UFC) 3-430-09N,
"Exterior Mechanical Utility Distribution."
NOTE: Following information shall be shown on project drawings:
1. Only drawings (not specifications) shall indicate capacity, efficiency,
dimensions, details, plan view, sections, elevations, and location of equipment;
and space required for equipment maintenance.
2. Configuration, slope, and sizes for concrete trench and for each piping
system.
3. Location, sizes, and type of each valve and each trap.
4. Details of expansion joints and expansion loops for piping.
5. Capacity, sizes, bypass valves, and piping for steam flow meters and pressure
regulating valves.
6. Scale ranges for pressure gages and thermometers.
7. Whether piping is run in shallow concrete trenches, aboveground on pedestals
or poles, on piers, under piers, in trenches on piers, or in manholes.
8. Details, sections, and elevations of shallow concrete trenches and manholes,
piping within trenches and manholes, and piping aboveground.
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.
| ASME INTERNATIONAL (ASME) |
| |
| ASME B16.11 | | (2002) Forged Fittings, Socket-Welding and Threaded |
| |
| ASME B16.20 | | (2000) Metallic Gaskets for Pipe Flanges - Ring-Joint,
Spiral Wound, and Jacketed |
| |
| ASME B16.3 | | (1998) Malleable Iron Threaded Fittings |
| |
| ASME B16.34 | | (1996) Valves Flanged, Threaded, and Welding
End |
| |
| ASME B16.39 | | (1998) Malleable Iron Threaded Pipe Unions |
| |
| ASME B16.5 | | (2003) Pipe Flanges and Flanged Fittings |
| |
| ASME B16.9 | | (2003) Factory-Made Wrought Steel Buttwelding
Fittings |
| |
| ASME B31.1 | | (2004) Power Piping |
| ASTM INTERNATIONAL (ASTM) |
| |
| ASTM A 106 | | (2002a) Seamless Carbon Steel Pipe for High-Temperature
Service |
| |
| ASTM A 193/A 193M | | (2004c) Alloy-Steel and Stainless Steel Bolting
Materials for High-Temperature Service |
| |
| ASTM A 194/A 194M | | (2004a) Carbon and Alloy Steel Nuts for Bolts
for High Pressure or High Temperature Service
or Both |
| |
| ASTM A 36/A 36M | | (2004) Carbon Structural Steel |
| |
| ASTM A 53 | | (1999b) Pipe, Steel, Black and Hot-Dipped, Zinc-Coated,
Welded and Seamless |
| |
| ASTM A 615/A 615M | | (2004b) Deformed and Plain Billet-Steel Bars
for Concrete Reinforcement |
| |
| ASTM C 920 | | (2002) Elastomeric Joint Sealants |
| |
| ASTM D 229 | | (2001) Rigid Sheet and Plate Materials Used
for Electrical Insulation |
| MANUFACTURERS STANDARDIZATION SOCIETY OF THE VALVE AND FITTINGS INDUSTRY (MSS) |
| |
| MSS SP-58 | | (2002) Pipe Hangers and Supports - Materials,
Design and Manufacture |
| |
| MSS SP-69 | | (2002) Pipe Hangers and Supports - Selection
and Application |
| |
| MSS SP-70 | | (1998) Cast Iron Gate Valves, Flanged and Threaded
Ends |
| |
| MSS SP-71 | | (1997) Gray Iron Swing Check Valves, Flanged
and Threaded Ends |
| |
| MSS SP-80 | | (2003) Bronze Gate, Globe, Angle and Check Valves |
| |
| MSS SP-85 | | (2002) Cast Iron Globe & Angle Valves, Flanged
and Threaded Ends |
1.2 SYSTEM DESCRIPTION
Provide [new and modify existing] exterior [steam and condensate] [hot water] piping system of shallow concrete
trench type, complete and ready for operation. [Provide piping to and including main steam pressure regulating
valves, bypass valves, safety-relief valves, and high pressure traps within each building.] Design pressure
and temperature ratings of system components shall be for [working pressure of 1034 kPa (gage) 150 psig steam
at 186 degrees C 366 degrees F and 862 kPa (gage) 125 psig condensate at 121 degrees C 250 degrees F] [hot water
at 232 degrees C 450 degrees F].
1.3 SUBMITTALS
NOTE: Review submittal description (SD) definitions in Section 01330 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
01330
01330
01330 SUBMITTAL PROCEDURES:
SD-02 Shop Drawings
Piping system[; G][; G, [_____]]
Pipe hangers and supports[; G][; G, [_____]]
Manholes[; G][; G, [_____]]
Shallow concrete trench[; G][; G, [_____]]
SD-03 Product Data
Pipe
Valves[; G][; G, [_____]]
Strainers[; G][; G, [_____]]
Pipe hangers and supports
Traps
Gages
Steam flow meters[; G][; G, [_____]]
Expansion joints[; G][; G, [_____]]
Manhole drainers[; G][; G, [_____]]
Sealant
SD-07 Certificates
Certification of welder's qualifications
SD-10 Operation and Maintenance Data
Manhole drainers, Data Package 2; [; G][; G, [_____]]
Steam flow meters, Data Package 2; [; G][; G, [_____]]
Submit in accordance with Section
01781
01781
01781 OPERATION AND MAINTENANCE DATA.
1.4 QUALITY ASSURANCE
1.4.1 Certification of Welder's Qualifications
Submit prior to site welding. Certification shall not be more than one year old.
PART 2 PRODUCTS
2.1 PIPE
[Steam piping includes piping upstream of steam traps. Condensate piping includes piping downstream of steam
traps.]
2.1.1 [Steam] [Hot Water] Pipe
a. ASTM A 53: Type E (electric-resistance welded, Grade A or B) or Type S (seamless, Grade
A or B), black steel. Provide Weight Class STD (Standard) for welding end connections. Provide
Weight Class XS (Extra Strong) for threaded end connections.
b. ASTM A 106: Grade A or B, black steel, Schedule No. 40 for pipe sizes through 250 mm 10
inches, and minimum pipe wall thickness of 9.50 mm 0.375 inch for pipe sizes 300 mm 12 inches
and larger for welding end connections. Provide Schedule No. 80 for threaded end connections.
2.1.2 Condensate Pipe
a. ASTM A 53: Type E (electric-resistance welded, Grade A or B) or Type S (seamless, Grade
A or B); black steel, Weight Class XS (Extra Strong).
b. ASTM A 106: Grade A or B, black steel, Schedule No. 80.
2.1.3 Buried Steel Piping to Cooling Well or Drain
Provide direct buried steel condensate pipe and fittings with exterior coal tar epoxy painting system.
2.2 FITTINGS
2.2.1 Threaded Fittings
ASME B16.11, or ASME B16.3, Class [150 for steam, Class 300 for condensate] [300 for hot water].
2.2.2 Socket-Welding Fittings
ASME B16.11.
2.2.3 Buttwelding Fittings
ASME B16.9. Provide same material and weight as piping in which fittings are installed. Backing rings shall
conform to ASME B31.1 and be compatible with materials being welded.
2.2.4 Eccentric Reducing Fittings
ASME B16.9. Provide same material and weight as piping in which fittings are installed.
2.2.5 Flanges and Unions
a. Flanges: ASME B16.5, Class [150 or Class 300 as required] [300 for hot water].
b. Unions: ASME B16.39, Class [150 for steam, Class 250 for condensate] [300 for hot water].
2.2.6 Gaskets, Bolts, Nuts, and Washers
a. Gaskets: Provide gaskets suitable for the intended service. Provide spiral wound, non-asbestos
gasket with centering ring per ASME B16.20.
b. Bolts: ASTM A 193/A 193M, Grade B7. Extend a minimum of two full threads beyond the nut
with the bolts tightened to the required torque.
c. Nuts: ASTM A 194/A 194M, Grade 7, with Teflon coated threads.
d. Washers: Provide steel flat circular washers under bolt heads and nuts.
e. Electrically Isolating (Insulating) Gaskets for Flanges: Provide ASTM D 229 electrical
insulating material of 1000 ohms minimum resistance. Provide one piece factory cut insulating
gaskets between flanges. Provide silicon-coated fiberglass insulating sleeves between bolts
and holes in flanges; bolts may have reduced shanks of a diameter not less than diameter at
root of threads. Provide 3.20 mm 0.125 inch thick high-strength insulating washers next to
flanges and provide stainless steel flat circular washers over insulating washers and under
bolt heads and nuts. Provide bolts 13 mm 0.5 inch longer than standard length to compensate
for thicker insulating gaskets and washers under bolt heads and nuts.
2.3 VALVES
Provide with stems in the horizontal position or not greater than 45 degrees above the horizontal position.
Valves shall have flanged end connections, except sizes smaller than 65 mm 2.5 inches may have union end connections,
or threaded end connections with a union on one side of valve.
2.3.1 Valves for [Steam] [Hot Water] Service
Valves [upstream of steam traps] shall be steel body for minimum working pressure of ASME Class [150] [300 for
hot water].
a. Gate Valves, Globe Valves, Angle Valves, and Check Valves: ASME B16.34, steel body, minimum
of ASME Class [150] [300 for hot water]. Provide swing check valves.
b. Steam Pressure Regulating Valves: Steel body, minimum of ASME Class 150, except as modified
herein. Valve seats and disc shall be of replaceable heat-treated stainless steel. Valves
shall be single seated; seat tight under dead end conditions, and move to the closed position
in the event of pressure failure of the operating (controlling) medium. Provide strainer in
inlet from external operating (controlling) medium. Valves shall be controlled by pilot valve
with strainer at inlet from external pressure sensing piping. Valves shall be internally or
externally steam traced for freeze protection. Valves shall be piston operated type or spring
loaded diaphragm operated type with stainless steel springs.
c. Safety-Relief Valve: Minimum of ASME Class [150] [300 for hot water], with test lever.
Valves shall have steel [or copper alloy] body with flanged inlet and outlet connections or
threaded connections attached to threaded ASME Class [150] [300 for hot water] flanges. Valves
shall be ASME rated for capacity indicated.
2.3.2 Valves for Condensate Service
Valves downstream of steam traps shall be for minimum working pressures of ASME Class 125.
a. Gate Valves: MSS SP-80, except sizes 65 mm 2.5 inches and larger shall conform to MSS SP-70
.
b. Globe and Angle Valves: MSS SP-80, except sizes 65 mm 2.5 inches and larger shall conform
to MSS SP-85.
c. Check Valves: MSS SP-80, except sizes 65 mm 2.5 inches and larger shall conform to MSS SP-71
. Provide swing check valves.
2.4 PIPING ACCESSORIES
2.4.1 Pipe Hangers and Supports
Provide MSS SP-58 and MSS SP-69, Type 46, of the adjustable type, except as specified or indicated otherwise.
Tack-welded Type 39 pipe covering protection saddles to steel pipe for insulated piping. Provide steel support
rods. Finish of rods, nuts, bolts, washers, hangers, and supports shall be hot-dip galvanized after fabrication.
Rollers, bases, and saddles may be painted with two coats of aluminum or light gray paint rated for use on hot
metal surfaces up to 232 degrees C 450 degrees F in lieu of hot-dip galvanized. Axles for rollers shall be stainless
steel. Miscellaneous metal shall conform to ASTM A 36/A 36M, hot-dip galvanized after fabrication.
2.4.2 Strainers
Construct of steel in accordance with ASME B16.5 for minimum of ASME Class [150] [300 for hot water]. Provide
stainless steel strainer element with perforations of [0.40 mm0.016 inch for steam, 0.80 mm 0.031 inch for steam
mixed with condensate, and] 1.20 mm 0.047 inch for [condensate (hot water)] [hot water]. Provide blow-off outlet
with pipe nipple, gate valve, and discharge pipe nipple.
2.4.3 Traps
Steel body, internals of stainless steel, minimum of ASME Class 150, and of the types indicated.
2.4.4 Gages
Provide single style pressure gage with 115 mm 4.5 inch dial, brass or aluminum case, bronze tube, gage cock,
pressure snubbers, and syphon. Provide scale range for the intended service.
2.4.5 Pipe Sleeves
Provide where piping passes entirely through walls and floors. Provide sleeves of sufficient length to pass
through entire thickness of walls and floors. Provide 25 mm one inch minimum clearance between exterior of piping
or pipe insulation, and interior of sleeve or core-drilled hole. Firmly pack space with mineral wool insulation.
Seal space at both ends of sleeve or core-drilled hole with plastic waterproof cement which will dry to a firm
but pliable mass, or provide mechanically adjustable segmented elastomeric seal. In fire walls and fire floors,
seal both ends of sleeves or core-drilled holes with UL listed fill, void, or cavity material.
a. Sleeves in Masonry and Concrete Walls and Floors: Provide hot-dip galvanized steel, ductile-iron,
or cast-iron sleeves. Core drilling of masonry and concrete may be provided in lieu of sleeves
when cavities in the core-drilled hole are completely grouted smooth.
b. Sleeves in Other Than Masonry and Concrete Walls and Floors: Provide 26 gage galvanized
steel sheet.
2.4.6 Escutcheon Plates
Provide split hinge type metal plates for piping entering walls and floors in exposed spaces. Provide polished
stainless steel plates or chromium-plated finish on copper alloy plates in finished spaces. Provide paint finish
on metal plates in unfinished spaces.
2.4.7 Electronic Steam Flow Meters
Meter shall be for minimum working pressure of ASME Class [150] [300]. Meter shall include an orifice plate,
pressure transmitter, indicator, and totalizer. Provide meter for measuring steam flow in kg per second pounds
per hour. Meter shall be for installation and operation in horizontal position.
a. Orifice Plate: Provide differential producing type orifice plate with circular hole for
insertion into steam piping between two ASME B16.5 Class 300 welding neck orifice flanges.
Orifice plate shall be Type 304 stainless steel. Furnish a dimensional report and flow versus
differential curve with accuracy of plus or minus one percent over a 5 to 1 flow range. Orifice
flanges shall have at least two radially-drilled and tapered holes for metering and two jack
screws.
b. Pressure Transmitter: Provide solid state electronic type differential pressure transmitter.
Transmitter shall utilize Type 316 stainless steel dual opposed rupture-proof bellows converted
to produce a 4 to 20 mA dc output. Transmitter shall have a flow range of 0 to 0.40 kg per
second 3000 pounds per hour of steam flow with accuracy of plus or minus 2 percent of full scale
over a 5 to 1 flow range. House transmitter in a weatherproof enclosure designed for wall mounting.
Bellows body shall be rated for not less than 6894 kPa (gage) 1000 psig. Power requirements
are 120 volts ac. Provide transmitter complete with condensate reservoirs, steel three-valve
manifold for isolation and nulling, and blowdown valves.
c. Indicator: Provide electric indicator to continuously indicate steam flow by means of a
4 to 20 mA dc electrical input signal. Indicator shall have pivot and jewel suspension and
a mirrored scale with uniform graduations over a steam flow range of 0 to 0.40 kg per second
3000 pounds per hour.
d. Totalizer: Provide totalizer that linearizes a 4 to 20 mA dc electrical input signal into
digital signal scaled in kg pounds of steam flow, displays totalized steam flow on a six-digit
nonresettable counter, and transmits each totalizer count to the output.
e. Output: An isolated, 500 volt minimum, ac or dc switch closure rated at 50 volts dc or
40 volts RMS ac, one ampere minimum capacity. Duration of closure shall be not less than 0.04
second or more than 0.06 second.
2.4.8 Steam Flow Meters
NOTE: Meters can have (a) six-dial counter, or (b) pressure compensated six-dial
counter, or (c) remote totalizer, or (a) and (c). Meters cannot have (a) and
(b), or (b) and (c).
Meter shall be for minimum working pressure of ASME Class [150] [300] with steel pressure chambers [or ASME Class
250 with cast-iron pressure chambers]. Provide meter in horizontal pipe between two ASME B16.5 welding neck
flanges. Provide rotary type meter for flow integration. Working parts shall be stainless steel or brass.
Steam flow shall cause rotation of a rotor assembly at a speed directly proportional to rate of steam flow, as
controlled by a damping liquid. Rotational speed of rotor assembly shall be reduced by gearing in damping liquid
chamber. Final drive to exterior counter shall be by driving magnets; stuffing box shall not be allowed. Counter
shall be enclosed in dust-tight cast-aluminum housing attached to, but easily removable from, meter. For steam
pipe main sizes 100 mm 4 inches and smaller, provide meter directly in steam piping. For steam pipe main sizes
larger than 100 mm 4 inches, provide meter in shunt bypass piping with two ASME B16.5 Class 300 welding neck
orifice flanges in steam pipe main. In shunt bypass piping, provide two flanged gate valves calibrated by meter
manufacturer. In steam pipe main, provide 3.20 mm 0.125 inch thick stainless steel orifice plate sized to suit
meter capacity between two ASME B16.5 Class 300 welding neck orifice flanges. [Provide six-dial counter with
electrical contactor to transmit signal to data terminal cabinet (DTC) for indicating steam flow in kg pounds
.] [Provide pressure compensated six-dial counter to automatically and continuously correct steam flow meter
readings for steam pressure variations.] [Provide remote totalizer for recording steam flow in kg pounds.]
2.4.9 Guided Slip Tube Expansion Joints
Internally-externally guided type, injected semiplastic type packing, with service outlets. Joints shall be
for minimum working pressure of ASME Class [150] [300]. Provide single or double slip tube type as indicated.
Provide flanged or buttwelding end connections as indicated.
2.4.10 Flexible Ball Expansion Joints
Provide chromium plated steel balls capable of 360 degree rotation plus 15-degree angular flex movement. Provide
pressure molded composition gaskets for continuous operation temperature of 274 degrees C 525 degrees F. Joints
shall be designed for minimum working pressure of ASME Class [150] [300]. Provide flanged or buttwelding end
connections as indicated.
2.4.11 Bellows Expansion Joints
Type 304 stainless steel corrugated bellows, reinforced with rings, internal sleeves, and external protective
covers or externally pressurized joints. Provide limit stops to limit total movement in both directions. Cold
set joints to compensate for temperature at time of installation. Joints shall withstand 10,000 cycles over
a 20 year period. Joints shall be for minimum working pressure of ASME Class [150] [300]. Provide single or
double bellows expansion joint as indicated. Provide first pipe alignment guide no more than four pipe diameters
from expansion joints; provide second pipe alignment guide no more than 14 pipe diameters from the first guide.
Provide flanged or buttwelding end connections as indicated.
2.5 MANHOLE DRAINERS (EJECTORS)
Provide automatic type drainers to operate on 862 kPa (gage) 125 psig steam supply. Drainer shall operate when
water level rises sufficiently in the sump and shall pump water from the sump. When water level is lowered by
pumping action, pumping action shall stop until water again gathers in sump. Provide each drainer with controls
to accomplish above sequence of operation. Drainer shall be constructed of stainless steel or corrosion-resistant
copper and bronze. Piping from manhole drainers shall be ASTM A 53, Weight Class XS (Extra Strong), hot-dip
galvanized steel pipe with ASME B16.11 or ASME B16.3 Class 300, hot-dip galvanized threaded fittings. Provide
steam pressure regulating valve assembly for manhole drainers for operation on steam system above 862 kPa (gage)
125 psig.
2.6 CONCRETE MANHOLES
Provide under this section as specified in Section
03300N
03300N
03300N CAST-IN-PLACE CONCRETE, except as modified herein.
Concrete shall be of
30 MPa 4000 psi minimum 28 day compressive strength, air-entrained admixture (
133 grams
per cubic meter3.6 ounces per cubic yard), with water-reducing admixture (
814 grams per cubic meter22 ounces
per cubic yard), reinforced with deformed steel bars. Construct manhole sides by one monolithic pour. Cast-iron
steps with non-slip surfaces and spaces
300 to 400 mm 12 to 16 inches apart on centers shall be firmly embedded
in concrete walls for access to bottom of manholes. Provide top of manhole as indicated.
2.7 NAMEPLATES
Provide laminated plastic nameplates for equipment, gages, thermometers, and valves. Nameplates shall be melamine
plastic, 3.20 mm 0.125 inch thick, black with white center core. Surface shall be matte finish. Corners shall
be square. Accurately align lettering and engrave into the white core. Minimum size of nameplates shall be
25 by 65 mm 1 by 2.5 inches. Lettering shall be minimum of 6.40 mm 0.25 inch high normal block style. Key the
nameplates to a chart and schedule for each system to identify its function. Frame charts and schedules under
glass, and locate where directed near each system. Furnish two copies of each chart and schedule.
2.8 SHALLOW CONCRETE TRENCH
a. Cast-in-Place Concrete: Provide concrete as specified in Section
03300N
03300N
03300N CAST-IN-PLACE CONCRETE,
except as modified herein. Concrete shall be 30 MPa 4000 psi minimum 28 day compressive strength,
air entrained admixture (133 grams per cubic meter3.6 ounces per cubic yard), with water-reducing
admixture (814 grams per cubic meter22 ounces per cubic yard), reinforced with ASTM A 615/A 615M
deformed steel bars.
b. Precast Concrete: Provide as specified in Section
03410
03410
03410 PRECAST[ PRESTRESSED] STRUCTURAL
CONCRETE, except as modified herein. Concrete shall be 30 MPa 4000 psi minimum 28 day compressive
strength, air-entrained.
c. Gasket Material: Provide neoprene pad, not less than 50 mm 2 inch wide by 6.40 mm 0.25
inch thick, between concrete trench covers and concrete trench wall tops.
d. Backing Rods: Provide compressible, nonshrinkable, nonreactive with joint sealant and nonabsorptive
type such as upholstery cord, cotton, jute, or plastic rod, all free of oils or bitumens.
e. Separating Tape: Provide polyethylene or polyester tape, 0.08 mm 3 mil minimum thickness
or masking tape, rubber tape, or other barrier sheet, nonreactive, nonabsorptive, adhesive-back
tape, 3.20 mm 0.12 inch wider than normal width of the joint.
f. Dowel Bars: Provide ASTM A 615/A 615M including supplementary requirements (S1), Grade
40 or 60 for plain billet-steel concrete reinforcement bars. Coat sliding portion of each bar
with lacquer resisting primer. Remove burrs and projections from the bars. Fit the outer end
of the sliding portion of each dowel with a tight-fitting metal sleeve which conforms to manufacturer's
recommendation for the dowel bars.
g. Exterior Sealant: ASTM C 920, Type S or Type M, Class 25. Provide Grade NS, Use NT, sealant
for joints in vertical surfaces. Provide Grade P, Use T, sealant for joints in horizontal surfaces.
PART 3 EXECUTION
3.1 INSTALLATION
Installation of exterior heat distribution system including equipment, materials, workmanship, fabrication, assembly,
erection, examination, inspection, and testing shall be in accordance with ASME B31.1, except as modified herein.
Install piping straight and true to bear evenly on supports and sand bedding material. Install valves with stems
horizontal or above centerline of pipe. Provide flanges or unions at valves, traps, strainers, connections to
equipment, and as indicated.
a. Cleaning of Piping: Keep the interior and ends of new piping and existing piping affected
by the Contractor's operations, cleaned of water and foreign matter during installation by using
plugs or other approved methods. When work is not in progress, securely close open ends of
pipe and fittings to prevent entry of water and foreign matter. Inspect piping before placing
into position.
b. Demolition: Remove materials so as not to damage materials which are to remain. Replace
existing work damaged by the Contractor's operations with new work of the same construction.
3.2 PIPING
Test, inspect, and approve piping before burying, covering, or concealing. Provide fittings for changes in direction
of piping and for connections. Reducing branch connections in steel piping may be made with forged branch outlet
reducing fittings for branches two or more pipe sizes smaller than mains. Branch outlet fittings shall be forged,
flared for improved flow where attached to pipe, reinforced against external strains, and designed to withstand
full pipe bursting strength. Stab type connections will not be permitted. Jointing compound for pipe threads
shall be Teflon pipe thread paste. Pipe nipples 150 mm 6 inches long and shorter shall be Schedule 80 steel
pipe. Make changes in piping sizes through tapered reducing fittings; bushings will not be permitted.
a. Fittings and End Connections: For sizes less than 25 mm 1 inch provide threaded fittings
and end connections. For sizes 25 to 50 mm 1 to 2 inches provide threaded or socket-welding
or buttwelding fittings and end connections; provide threaded connections for threaded valves,
traps, strainers, and threaded connections to equipment. For sizes 65 mm 2.5 inches and larger
provide buttwelding fittings and end connections; provide flanged connections for flanged valves,
traps, strainers, and flanged connections to equipment.
b. Welding: ASME B31.1, metallic arc process, including qualification of welders.
c. Pipe Hangers and Supports: Provide additional hangers and supports for concentrated loads
in piping between hangers and supports, such as for valves. Support steel piping as follows:
MAXIMUM SPACING (METER)
Pipe Size 25 and
(mm) Under 40 50 80 100 150 200 250 300
Steel Piping 2.70 3.70 4.00 4.60 5.20 6.40 7.30 8.00 9.20
MAXIMUM SPACING (FEET)
Pipe Size One and
(Inches) Under 1.5 2 3 4 6 8 10 12
Steel Piping 9 12 13 15 17 21 24 26 30
3.3 FIELD QUALITY CONTROL
3.3.1 Inspections
Prior to initial operation, inspect piping system for compliance with drawings, specifications, and manufacturer's
submittals.
3.3.2 Piping Tests
Before final acceptance of the work, test each system as in service to demonstrate compliance with contract requirements.
Before insulation is applied, hydrostatically test each piping system at not less than [1551] [3447] kPa (gage)
[225] [500] psig in accordance with ASME B31.1, with no leakage or reduction in gage pressure for 2 hours.
Flush and clean piping before placing in operation. Flush piping at a minimum velocity of 2.40 meters per second
8 fps. Correct defects in work provided by Contractor and repeat tests until work is compliance with contract
requirements. Furnish potable water, electricity, instruments, connecting devices, and personnel for tests.
3.4 FIELD PAINTING
After completion of field inspections and tests, clean and paint metal surfaces exposed to weather and in manholes,
including valves, strainers, traps, flow meters, pipe flanges, bolts, nuts, washers, pipe hangers, support, expansion
joints, manhole drainers, and miscellaneous metal. Do not paint piping prior to the application of field-applied
insulation. Do not paint stainless steel or aluminum jackets. Apply paint to clean dry surfaces. Clean surfaces
to remove dust, dirt, rust, oil, and grease. Provide surfaces with two coats of enamel paint applied to a total
minimum dry film thickness of 0.05 mm 2 mils. Apply the second coat of paint after the preceding coat is thoroughly
dry. Color of finish coat shall be aluminum or light gray. Paint shall be rated for use on hot metal surfaces
up to 232 degrees C 450 degrees F and for use on surfaces exposed to weather.
3.5 CONNECTIONS TO EXISTING SYSTEMS
Notify Contracting Officer in writing at least 15 days prior to date the connections are required. Obtain approval
before interrupting service.Provide materials required to make connections into existing systems and perform
excavating, backfilling, compacting, and other incidental labor as required.
-- End of Section --