MIL-HDBK-1022A
c) In all cases, ensure the effective screen area is
not less than three times the cross sectional area of the
pipe.
3.6.7
Surge Suppressors. Every effort should be made to
control hydraulic surge or shock to acceptable limits by the
design of the piping system rather than by the use of surge
suppressors. Where this is not possible or becomes extremely
impractical, a surge suppressor(s) may be incorporated. Use
the diaphragm or bladder type equipped with a top-mounted
liquid-filled pressure gauge, isolation valve, and drain.
Locate surge suppressors as close as possible to the point of
shutoff that is expected to cause the shock. Provide wafer
check valve at the bottom with adjustable pin steps to permit
controlled bleed back of the surge suppresser without
rebounding.
3.6.8
Pumps
3.6.8.1
Design Requirements. Design pumps to deliver the
full range of operating conditions anticipated at any facility
with flow rates as presented in Section 2 of this handbook.
Ensure pumps develop sufficient head to overcome the friction
and static head losses in the system at the rated flow.
Consider the specific gravity, temperature, viscosity, vapor
pressure, corrosive, and solvent properties of the fuel. If a
range is given for the specific gravity, etc., in par. 2.3,
use the larger value for the purpose of calculations. For any
single grade of fuel, connect pumps in parallel. Select
according to the type most suitable for the particular
application. Do not use positive displacement or
reciprocating pumps for product issue or pipeline transfer.
Provide enough pumps to allow the system to operate at full
capacity with the largest pump out-of-service.
3.6.8.2
Centrifugal Pumps. Use API Std 610 centrifugal
pumps to pump from aboveground tanks with continuously flooded
suctions.
3.6.8.3
Vertical Turbine Pumps. Use API Std 610 vertical
turbine pumps to pump from underground tanks. Do not use
horizontal transfer pumps in a pit alongside the underground
tank as an alternative.
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