- 17 -
- 17 -
Operation
2. Operation
1. Fully close a discharge valve and fully open a suction valve.
2. Prime the pump.
• If the pump is in flooded suction system, fully open both discharge and suction valves.
• If the pump is other than flooded suction system, prime the suction piping as well as the pump.
3. Check rotating direction of the motor.
• Close a discharge valve. Power the motor for a quick moment (within a second) in order to check the
rotation direction. A correct direction is shown with an "arrow" mark on the pump (Clockwise seen from
motor fan side).
• Check if the motor fan smoothly stops when it is powered off.
NOTE: If the motor does not stop smoothly, check rotating parts.
4. Air elimination
• Before full operation, eliminate the air in the pump.
• Fully open the valve on the air bleed piping. Run the pump for one second and repeat it 3 to 5 times for
air elimination.
• After the air elimination, fully close the discharge valve.
NOTE:
In case air bleed piping is not equipped, repeat the momentary run several times
with a discharge valve open.
5. Starting operation
• Start the pump with a discharge valve fully closed. Stop the closed-discharge operation within one minute.
• Confirm that discharge pressure rises to the shut off pressure.
• Gradually open discharge valve to obtain the specified pressure (capacity).
NOTE: Pay attention to the over-load caused by an excessively opened valve.
Precautions on operation
1. Check for loose bolts on the pump. Retighten the rear casing support mounting bolts by the specified
torque of 85N•m.
2. When the pump keeps running in negative rotation, the pump breaks.
3. Closed-discharge operation should be within one minutes.
4. Make sure that a flow rate is always equal to or more than the minimum one. The operation below the mini-
mum flow can reduce the lubricant and cooling functions on the sliding parts. This could lead to failure.
Minimum discharge capacity is 50 /min.
3. Shutdown
1. Slowly close a discharge valve.
Quick closing by a solenoid valve may cause water hammer and damages the pump. Be sure to slowly
close any discharge valve.
2. Switch off and stop the pump.
Check that the pump stops smoothly. If the pump stops roughly, inspect it.
NOTE:
When leave the pump stopped for a long period,
take a countermeasure against
freezing for the prevention of freeze in the pump and piping. In case a blackout inter-
rupts the pump operation, switch off the pump and close discharge valves.
