UFC 4-390-01
23 July 2003
c)
McCarty, R.D. Hydrogen:
Its Technology and
Implications. CRC Press, Inc., 1975.
d)
NASA Hydrogen Safety Handbook.
e)
Standard for Purged Enclosures for Electrical
Equipment in Hazardous (Classified) Areas. NFPA 496,
National Fire Protection Association, 1989.
f)
Standard for Gaseous Hydrogen Systems at Consumer
Sites.
NFPA 50A, National Fire Protection Association, 1989.
B.8.2.2
Components of Fluids Pressurized Systems.
B.8.2.2.1 Pumps. Pump selection should be based upon the system
fluid, the operating pressure and the flow capacity that is
required. Once these operating parameters have been determined,
pump selection is determined by an overlay of system and pump
curves. Pumps should be located to maximize the net positive
suction head and to minimize air entrainment into the system.
Pumps should be equipped with one pressure relief valve per each
stage. Each stage of a pump should be provided with a
temperature gauge for monitoring bearing temperature and with a
pressure gauge. When pumping potentially contaminated fluids, a
filter should be provided upstream of the pump to remove debris
that could cause pump/system inefficiencies (e.g., cracked
impeller, build-up in suction and discharge piping). The filter
should be placed in an easily accessible location for ease of
maintenance.
When installing pumps, consideration should be given to
minimizing the effects of vibrations when choosing foundation
mountings and piping connections. Consult with the
manufacturer's recommendations for installation.
When high flow and low-pressure conditions are needed,
centrifugal pumps should be considered for use. If these pumps
are used in series, ensure that each pump is rated for the proper
inlet pressure (i.e., the inlet pressure will increase for each
consecutive pump).
When low flow and high-pressure conditions are needed, positive
displacement pumps should be considered for use. This type of
pump should also be considered when pumping high viscous fluids
(i.e., if the viscosity is the same as or greater than SAE-30
motor oil (at room temperature)). Positive displacement pumps
may also be used for metering flow. Some examples are external
gear pumps and sliding vane pumps.
B.8.2.2.2 Valves. Valves should be selected based upon the
system fluid, operating pressure and flow capacity that are
required. Valves produced to a commercial or military standard
are acceptable as long as the design pressure of the valve meets
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