2.7.1
Underground Tanks
UL listed, [double walled] fiberglass coated steel tanks. Provide exterior
surfaces of steel tanks with a glass reinforced isophthalic polyester resin
of sufficient thickness to resist 35,000-volt Holiday test. Provide
automatic monitoring system with audible alarms to continuously monitor
leaks.
2.7.2
Tank Insulations and Jackets
Comply with Section 15080 THERMAL INSULATION FOR MECHANICAL SYSTEMS.
Separate aboveground tanks from supports with insulation.
2.8
HEAT EXCHANGERS
**************************************************************************
NOTE: Where potable fluids are not used, double
wall and vented construction provides fail-safe leak
detection without attendance by any operator. If
the operator is not present, sound alarms may not be
heard, and visual indicators may not be observed in
some cases. For many years, industrial applications
commonly use shell-and-tube or tube-in-tube heat
exchangers. In recent years, some industrial
applications use plate-and-frame heat exchangers as
options. Plate-and-frame construction requires much
less space, i.e., from one tenth to one half of the
space required by shell-and-tube construction.
Plate-and-frame heat exchangers generally have high
heat transfer rates. Electropolished stainless
steel plates may be specified to minimize fouling.
Stainless steel heat exchangers should be used in
spas due to high temperature water and high
chlorination.
**************************************************************************
ASME BPVC SEC VIII, construction with ASME label for 1034 kPa (gage) 150
psig working pressure and 2068 kPa (gage) 300 psig factory-rating pressure.
[Provide automatic monitoring system with audible alarms to continuously
monitor leaks.] [Provide relief vent with a visual indicator to detect
leaks by the change of coloring in the heat transfer fluid.]
2.8.1
Plate-and-Frame Construction
[Stainless steel] [or] [monel] plates and carbon steel frames, with baked
epoxy-enamel, and shroud. Provide stainless steel side bolts and nozzles.
Provide one piece molded [nitrile rubber] [ethylene-propylene rubber viton]
[neoprene] [or] [butyl] gaskets. Fabricate heat exchangers with design
results of heat transfer coefficients greater than 5680 watt per square
meter degree C 1,000 Btu per square foot per hour per degree F.
2.8.2
[Shell and Tube] [or] [Tube in Tube] Construction
[Double wall vented], [straight tube] [or] ["U" tube] [as indicated]. Low
temperature water [mixture] shall pass through tubes. High temperature
water [mixture] shall pass through shells. Fabricate tubes from [16 mm5/8
inch] [or] [20 mm3/4 inch] od [stainless steel] [or] [seamless No. 20 BWG
cupro-nickel (90-10)]. Provide tube bundles removable through flanged
openings.
SECTION 13610N
Page 15
Previous Page
