suitable for the application, construction and size pipe involved.
2.6.6
Control Valve
Unless otherwise indicated, valves shall be indicating type in accordance
with NFPA 13. Valves 65 mm 2-1/2 inch and larger shall be flanged outside
screw and yoke (OS&Y) type.
2.6.7
Check Valve
Check valves 100 mm 4 inches and larger shall be flanged, swing type, cast
or ductile iron body and cover, cast or ductile iron clapper with
replaceable EPDM rubber facing. Valves shall be suitable for either
vertical or horizontal mounting and equipped with a removable handhole
cover. The direction of flow shall be indicated by an arrow cast in the
valve body. The valve body shall include plugged pipe thread connections
for a 50 mm 2 inch drain.
2.7
ABOVEGROUND PIPING SYSTEMS FOR AFFF CONCENTRATE
2.7.1
Pipe
Pipe shall be standard weight stainless steel conforming to ASTM A 312/A
312M, Grade TP 304L.
2.7.2
Fittings
Seamless socket weld type or flanged type fittings shall conform to ASTM A
403/A 403M, Grade WP 304L, and shall be compatible with the pipe. Grooved
type fittings and couplings shall be of Type 316 Stainless Steel conforming
to ASTM A 351/A 351M.
2.7.3
Pipe Hangers
Hangers shall be listed in UL Fire Prot Dir or FM P7825a and be of the type
suitable for the application, construction and size pipe involved.
2.7.4
Control Valves
Valve shall be indicating type with full port ball and operating handle
that indicates the on/off position of the valve. Unit shall be socket weld
or flanged type. Valve body and ball shall be of 316 stainless steel
complying with ASTM A 351/A 351M. The valve handle shall be provided with
a suitable and substantial means for securing the valve open with a
key-operated locking device.
2.8
ALARM CHECK VALVE ASSEMBLY
**************************************************************************
NOTE: Specify 1724 kPa (250 psi) rated valve for
applications where the working pressure exceeds, or
may exceed, 1207 kPa (175 psi).
**************************************************************************
Alarm check valve assembly shall be of the variable pressure type rated for
working pressures of [1207 kPa 175 psi] [1724 kPa 250 psi]. Assembly
shall be provided with standard trimmings including pressure gauges,
retarding chamber, alarm line vent, testing bypass, and necessary pipe,
fittings, and accessories required for a complete installation. Valve trim
SECTION 13955A
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