ITT Goulds 3655, Инструкции по установке, эксплуатации и обслуживанию

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5.3 Operating at reduced head
On motor driven pumps, when discharge head or pressure is allowed to drop considerably below the rat-
ed point for any length of time, the motor should be watched for heating because the pump capacity in-
creases rapidly with reduced head, as does horsepower consumption. If this condition is likely to persist,
arrangements should be made either to manually or automatically throttle the discharge valve to build up
head to a safe point.
5.4 Operating with surge conditions in line
If pump is installed with a quick closing valve in discharge line that closes when pump is running, danger-
ous pressure surges may be built up that can cause damage to the pump or line. In services of this kind,
some cushioning arrangement must be provided to protect the pumping equipment.
5.5 Operating under freezing conditions
When exposed to freezing conditions and pump is standing idle, liquid inside the pump should be
drained by removing drain plug in bottom of casing (100) and opening pipe plug at top.
5.3 Operating at reduced head
3655 Installation, Operation and Maintenance Instructions 19