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 a 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.
2.5.9.1
Sleeves in Masonry and Concrete
Provide steel pipe sleeves. Sleeves are not required where drain, waste,
and vent (DWV) piping passes through concrete floor slabs located on grade.
Core drilling of masonry and concrete may be provided in lieu of pipe
sleeves when cavities in the core-drilled hole are completely grouted
smooth.
2.5.9.2
Sleeves Not in Masonry and Concrete
Provide 0.55 mm 26 gage thick galvanized steel sheet pipe sleeves.
2.5.10
Escutcheon Plates
Provide one piece or split hinge metal plates for piping entering floors,
walls, and ceilings 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.
2.6
HEAT TAPE
Provide UL listed parallel conduction type heat tape, with electrical
characteristics indicated, and adjustable thermostat for outdoor
aboveground winterized piping. The heat trace system shall meet
requirements of the NFPA 70, Section 427. The tape shall not be affected
by direct sunlight, ambient temperature, operating temperature, rain, or
salt laden atmosphere.
2.6.1
Heat Tape Construction
Provide flexible, parallel circuit construction consisting of a continuous
self-limiting resistance, conductive inner core material between two
parallel copper bus wires, designed for cut-to-length at the job site and
for wrapping around valves and complex fittings. Self-regulation shall
prevent overheating and burnouts even where the cable overlaps itself.
a.
Provide end seals for ends of circuits.
Wire at the ends of
circuits are not to be tied together.
b.
Provide sufficient cable, as recommended by the manufacturer, to
keep the pipe surface at 1.1 degrees C 34 degrees F minimum during
winter outdoor design temperature as indicated, but not less than
the following:
(1) 80 mm 3 inch pipe and smaller with 25 mm one inch thick
insulation, 4 watts/0.3 m 4 watts/feet.
(2) 100 mm 4 inch pipe and larger 38 mm 1.5 inch thick insulation,
8 watts/0.3 m 8 watts/feet of pipe.
SECTION 15741N
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