In the process of maintenance, the diagnosis of fire pump faults is usually a key step. The following are several common faults and their elimination measures for everyone to diagnose fire pump faults.
1. No liquid provided, insufficient supply of liquid or insufficient pressure
1) The pump has not been filled with water or has not been properly vented
Solution: Check if the pump casing and inlet pipeline are completely filled with liquid.
2) The speed is too low
Solution: Check if the wiring of the motor is correct, if the voltage is normal, or if the steam pressure of the turbine is normal.
3) The system head is too high
Elimination measures: Check the water head of the system (especially friction loss).
4) The suction distance is too high
Solution: Check the existing net pressure head (inlet pipelines that are too small or too long can cause significant friction losses).
5) Impeller or pipeline blockage
Solution: Check for any obstacles.
6) Wrong rotation direction
Solution: Check the direction of rotation.
7) Air generation or leakage in the inlet pipeline
Solution: Check for air pockets and/or air leaks in the inlet pipeline.
8) The packing or seal in the stuffing box is worn, causing air to leak into the pump casing
Solution: Check the packing or seal and replace it as needed, check if the lubrication is normal.
9) Insufficient suction head when pumping hot or volatile liquids
Solution: Increase the suction head and consult with the manufacturer.
10) The bottom valve is too small
Solution: Install the bottom valve of the correct size.
11) Insufficient immersion depth of bottom valve or inlet pipe
Solution: Consult the manufacturer for the correct immersion depth. Eliminate eddy currents with baffles.
12) The clearance between the impeller is too large
Solution: Check if the gap is correct.
13) Damaged impeller
Solution: Check the impeller and replace it as required.
14) The diameter of the impeller is too small
Solution: Consult the manufacturer for the correct impeller diameter.
15) The position of the pressure gauge is incorrect
Solution: Check if the position is correct and inspect the outlet nozzle or pipeline.
2. The fire pump will shut down after running for a while
1) The suction distance is too high
Solution: Check the existing net pressure head (inlet pipelines that are too small or too long can cause significant friction losses).
2) Impeller or pipeline blockage
Solution: Check for any obstacles.
3) Air generation or leakage in the inlet pipeline
Solution: Check for air pockets and/or air leaks in the inlet pipeline.
4) The packing or seal in the stuffing box is worn, causing air to leak into the pump casing
Solution: Check the packing or seal and replace it as needed. Check if the lubrication is normal.
5) Insufficient suction head when pumping hot or volatile liquids
Solution: Increase the suction head and consult with the manufacturer.
6) Insufficient immersion depth of bottom valve or inlet pipe
Solution: Consult the manufacturer for the correct immersion depth and use a baffle to eliminate eddy currents.
7) The sealing gasket of the water pump casing is damaged
Solution: Check the condition of the sealing gasket and replace it as required.
3. The power consumption of the fire pump is too high
1) Wrong rotation direction
Solution: Check the direction of rotation.
2) Damaged impeller
Solution: Check the impeller and replace it as required.
3) Rotating components bite to death
Solution: Check if the clearance between internal worn parts is normal.
4) Axis bending
Solution: Straighten the shaft or replace it as required.
5) The speed is too high
Solution: Check the winding voltage of the motor or the steam pressure delivered to the turbine.
6) The water head is lower than the rated value. Too much liquid is being pumped
Solution: Consult with the manufacturer. Install throttle valve and cut impeller.
7) The liquid is heavier than expected
Solution: Check the specific gravity and viscosity.
8) The packing box is not filled correctly (insufficient packing, not properly inserted or run in, too tight packing)
Solution: Check the packing and reload the packing box.
9) Incorrect lubrication of bearings or wear of bearings
Solution: Check and replace as required.
10) The running clearance between the wear-resistant rings is incorrect
Solution: Check if the gap is correct. Replace the wear-resistant ring of the water pump casing and/or impeller as required.
11) The stress on the pipeline on the pump casing is too high
Solution: Eliminate stress and consult with the manufacturer. After stress relief, check the alignment.
By following these fault diagnosis and maintenance measures, you can ensure that your fire pump system is always ready to respond effectively in case of emergencies. Proactive maintenance and regular inspections are key to ensuring the reliability and efficiency of fire pumps.
