WARNING:
Lock out driver power to prevent electric shock, accidental start-up and physical injury.
WARNING:
When installing in a potentially explosive environment, ensure that the motor is properly certi-
fied.
4.4.4
Lubricating lines to stuffing box
Lubricating liquid must be flowing to the stuffing box before the pump is started. Both mechanical seals
and packing require lubrication for continuous service.
4.4.5 Priming
The pump must be completely primed before operation.
WARNING:
Pumps must be fully primed at all times during operation.
4.4.6 Water hammer
Water hammer is a high pressure surge within a closed pipe system, created by rapid change in the flow
rate. Changes in the flow rate occur when there are sudden changes in pump speed. The most common
cause is the sudden opening or closing of a valve or flow control device.
Extensive damage to the pump and pipeline is a result of water hammer.
4.4.7 Freezing
If the pump is exposed to below freezing temperatures, the liquid should be drained during idle periods.
4.5 Locating problems
4.5.1 Conditions leading to insufficient or no discharge
•
Insufficient speed.
•
Excessive discharge head
•
Insufficient NPSH.
•
Worn pump components
•
Incorrect direction of rotation
•
Incomplete pump priming
•
Impeller or discharge pipe clogged
•
Pumpage viscosity too high
4.5.2 Conditions leading to excessive power consumption
•
Excessive speed.
•
Pump operating at high horsepower area of the pump curve (off design point)
4.5 Locating problems
24
Model JC Installation, Operation and Maintenance Instructions
