and outside walls.
3.1.1.8
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 threaded
end valve. [Place unions or flanges no farther apart than 30 meters 100
feet.] [Place unions or flanges as indicated.] Use unions on piping
smaller than 50 mm 2 inches in diameter, and use flanges on piping 50 mm 2
inches and larger in diameter. Provide 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.
Dielectric fittings shall utilize a non-metallic filler which will prevent
current flow. The spacer shall be suitable for the pressure and
temperature of the service. The fittings shall otherwise conform to the
requirements of paragraph entitled "Fittings."
3.1.1.9
Traps and Connections
Traps shall be of the type and capacity for the service and shall be
properly supported and connected. Except for thermostatic traps in pipe
coils, radiators, and convectors, install traps with a dirt pocket and
strainer between it and the piping or apparatus it drains. When necessary
to maintain in continuous service apparatus or piping which is to be
drained, provide a three-valve bypass so that the trap may be removed and
repaired and condensate may drain through the throttled bypass valve.
Provide a check valve on the discharge side of the trap whenever the trap
is installed for lift or operating against a back pressure, or discharges
into a common return line. When a thermodynamic trap is used, a check
valve is not required or recommended. Provide test connections on the
discharge side of the high and medium pressure traps when they are
specifically required. The test connection shall include a 15 mm 1/2 inch
globe valve with uncapped nipple.
3.1.1.10
Connections for Future Equipment
Locate capped or plugged outlets for connections to future equipment as
indicated.
3.1.2
Valves
3.1.2.1
General
Install valves in conformance with ASME B31.1, ASME BPVC SEC VIII D1, and
as required herein, at the locations indicated and elsewhere as required
for the proper functioning of the system. Use gate valves unless otherwise
directed. Install stop valves in the supply lines equipped or located so
as to permit operation from floor level, or provided with safe access in
the form of walkways or ladders. Install valves in positions accessible
for operation and repair. Provide gate valves 200 mm 8 inches and larger
with globe-valved bypass in accordance with MSS SP-45.
3.1.2.2
Globe Valves
Install globe valves so that the pressure shall be below the disk.
Install
globe valves with the stems horizontal on steam and exhaust lines.
SECTION 15183N
Page 27
Previous Page
