MIL-HDBK-1022A
station. Use programmable logic controllers (PLC) where
multiple pumps supply header loading multiple trucks or cars
to obtain desired flow rate to each loading station.
3.7.3.3
Pipeline Pumps. For pumps over 150 horsepower (112
kW), provide protective shutdown devices with alarm at central
supervisory control station in the event of the following:
a) High pump case temperature due to blocked
discharge.
b) Excessive pump vibration.
c) Mechanical seal or packing gland failure.
d) High discharge pressure or loss of discharge
pressure.
e) Excessive motor vibration.
f) High motor winding temperature.
g) Electrical interlocks which will prevent starting
a pump if certain key valve settings are not correct and which
will cause a pump shutdown if a key valve setting is changed.
h) Loss of pump suction pressure.
i) High bearing temperature and/or loss of cooling
water flow.
3.7.4
Temperature Controls. Provide temperature controls
at all fuel oil heaters to control the outlet oil temperature
within safe limits. Use controls in which each consists of a
sensing element in the fuel outlet line which activates a
thermostatic valve or switch in the heating medium supply
connection to the heater. Use a self-actuating control valve
that requires no external power for closure. Use a manually
adjustable set point for each temperature variable over the
desired temperature range. Provide a bypass around the
control valve with a V-port globe or ball valve for manual
operation.
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