MIL-HDBK-1022A
6.5.2.1
Locations. Provide valves in product piping systems
to control flow and to permit isolation of equipment for
maintenance or repair. Provide additional valves at required
locations necessary to conduct a valid hydrostatic test.
Provide manually operated valves, except where motor operators
are specifically authorized by applicable standard drawings or
technical specifications. As a minimum requirement, provide
block valves at the following locations:
a) On each branch line at the point of connection to
the main product pipeline or header.
b) On the product pipeline or header just before the
line leaves a pumping station.
c) On the inlet and outlet connection of each line
strainer, filter/separator, meter, automatic valve, and other
equipment that requires periodic servicing. One inlet valve
and one outlet valve may be used to isolate more than one
piece of adjacent equipment which are connected in series.
d) On the upstream and downstream side of each line
blind at connections to cross country pipelines.
e) On each main distribution pipeline immediately
downstream of the branch connection to each existing or future
operating storage facility served by the pipeline.
f) At intermediate points of approximately 10 miles
(16 km) in cross country distribution pipelines to facilitate
isolation of a section of the line for maintenance and repair.
g) On each side of water crossing exceeding 100 feet
(30 m) in width, and near the shoreline of a submerged sea
pipeline.
h) Do not use gate valves in fueling systems, except
where pipeline is piggable and absolute shut-off is not
required such as item (d) above.
i) At critical points where pipes cross under
runways, taxiways, and roadways.
j) For low-point drains and high-point vents.
113
Previous Page
