are not acceptable.
e.
Type 20 attachments used on angles and channels shall be furnished
with an added malleable-iron heel plate or adapter.
f.
Type 24 may be used only on trapeze hanger systems or on
fabricated frames.
g.
Type 39 saddles shall be used on insulated pipe 100 mm 4 inches
and larger when the temperature of the medium is 16 degrees C 60
degrees F or higher. Type 39 saddles shall be welded to the pipe.
h.
Type 40 shields shall:
(1)
Be used on insulated pipe less than 100 mm 4 inches
(2) Be used on insulated pipe 100 mm 4 inches and larger when the
temperature of the medium is 16 degrees C 60 degrees F or less.
(3) Have a high density insert for all pipe sizes. High-density
inserts shall have a density of 144 kg per cu. meter 9 pcf or
greater.
i.
Horizontal pipe supports shall be spaced as specified in MSS SP-69
and a support shall be installed not over 300 mm 1 foot from the
pipe fitting joint at each change in direction of the piping.
Pipe supports shall be spaced not over 1.5 meters 5 feet apart at
valves. Operating temperatures of 49 degrees C 120 degrees F for
PVC pipe and 82 degrees C 180 degrees F for CPVC shall be used in
determining hanger spacing for PVC or CPVC pipe. Horizontal pipe
runs shall include allowances for expansion and contraction.
j.
Vertical pipe shall be supported at each floor, except at
slab-on-grade, and at intervals of not more than 5 meters 15 feet,
nor more than 2 meters 8 feet from end of risers, and at vent
terminations. Vertical pipe risers shall include allowances for
expansion and contraction.
k.
Type 35 guides using steel, reinforced polytetrafluoroethylene
(PTFE) or graphite slides shall be provided to allow longitudinal
pipe movement. Slide materials shall be suitable for the system
operating temperatures, atmospheric conditions, and bearing loads
encountered. Lateral restraints shall be provided as needed.
Where steel slides do not require provisions for lateral
restraint, the following may be used:
(1) On pipe 100 mm 4 inches and larger when the temperature of
the medium is 16 degrees C 60 degrees F or higher, a Type 39
saddle, welded to the pipe, may freely rest on a steel plate.
(2) On pipe less than 100 mm 4 inches, a Type 40 shield, attached
to the pipe or insulation, may freely rest on a steel plate.
(3) On pipe 100 mm 4 inches and larger carrying medium less than
16 degrees C 60 degrees F, a Type 40 shield, attached to the pipe
or insulation, may freely rest on steel plate.
l.
Pipe hangers on horizontal insulated pipe shall be the size of the
outside diameter of the insulation. The insulation shall be
SECTION 15405A
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