right-of-way to accommodate pipe expansion cannot be identified and expansion
joints are required, they must be specified and located with installation
details noted on the drawings.
d) Provide a log of soil conditions along the piping right-of-way
which gives, as a minimum, soil type, soil resistivity and pH, bearing
strength and unstable conditions, and indicate corrective work required.
show pipe elevation, floor elevation, building wall construction, and existing
Underground. Use only approved and certified conduit systems for
steam, condensate and HTW, and procure and install in accordance with the
requirements of NFGS-02694, NFGS-02697, and NFGS-02698, respectively. The
Federal Agency Committee for Underground Heat Distribution Systems approves
and certifies the various types of conduit systems, i.e., drainable and
dryable (pressure testable), sectionalized, prefabricated (non-pressure
testable), and poured-in-place granular insulation type conduit systems.
Concrete shallow trench systems may be used only if the soil characteristics
set forth in NFGS-02693 are met. In this case, design and specify the system
in accordance with NFGS-02693.
Insulation. Evaluate insulation for all piping systems with the
potential for significant thermal losses. These include steam, condensate,
HTW, MTW, LTW, and CHW piping. Use NFGS-15250, Insulation of Mechanical
Systems, for CHW, LTW and special applications requiring insulation of fuel
gas and compressed air piping systems. Use NFGS-02696 for above-grade steam,
HTW, MTW, LTW, and condensate return piping systems. (Alternately, NFGS-15250
may be used for these above-grade piping systems.) Use aluminum jackets and
organic felt as specified in NFGS-15250 and NFGS-02696. Use NFGS-02694 for
not contain asbestos.
Miscellaneous Criteria. Anchor or guy exterior distribution
systems to withstand the wind velocity specified for design of structures,
refer to MIL-HDBK-1002/2, Loads.