MIL-HDBK-1005/7A
c)
Sluice Gates. Use AWWA Standard C501, Sluice
Gates, for guidance on sluice gates.
7.4.1.2
Special Purpose Valves . Consult manufacturers for
capacities and construction of the various types, to be used as
follows:
a)
Air Valves. Use air valves to release any air
collecting at high points in filling lines.
b)
Altitude Valves. Use altitude valves for supply
lines to
elevated tanks or reservoirs. These valves are
actuated
by the water level in the tanks or reservoirs, to close
when the
tank is full and open when the level on the system
pressure
lowers. Also refer to MIL -HDBK-1008C.
c)
Float Valves. Use float valves on supply lines
to fill tanks or reservoirs and maintain their water levels.
d)
Plug Valves.
Use for control of pumping rates at
low volume.
e)
Pressure Regulating Valves. Use pressure
regulating valves to deliver water from a high to a low pressure
system wherever the pressure downstream drops below a preset
value. In addition, these valves can be fitted to open when
upstream pressure drops below downstream pressure. Pressure
regulating valves on water distribution system should be located
in accordance with MIL -HDBK-1008C.
f)
Pressure Relief Valves. Use pressure relief
valves to relieve any pressure in tanks or pipelines above a
preset value.
g)
Vacuum Valves. Use vacuum valves to admit air
into tanks or pipelines for relieving vacuums induced by a break
or a rapid opening of valves.
7.4.2
Hydrants. Refer to criteria for hydrants for
distribution systems in MIL-HDBK-1008C and AWWA Manual M17,
Installation, Field Testing, and Maintenance of Fire Hydrants.
Use hydrants conforming to AWWA Standard C502, Dry-Barrel Fire
Hydrants; or to Underwriters Laboratories' Standard UL 246,
Hydrants for Fire Protection Services .
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