A. Failure phenomenon: The self-balancing wear-resistant multi-stage pump does not absorb water, the pointer of the pressure gauge and the vacuum gauge vibrates violently, or the vacuum gauge is in a high vacuum.
Cause Analysis:
1. The pump is not filled enough;
2. Air leakage in the suction pipe or meter;
3. The bottom valve is not opened;
4. The suction pipe is blocked;
5. The water absorption height is too large;
Solution:
1. Water injection and deflation;
2. Tighten the screw buckle;
3. Repair or replace the bottom valve;
4. Clean the suction pipe;
5. Lower the water absorption height.
B. Failure phenomenon: The self-balancing wear-resistant multi-stage pump pressure gauge is under pressure, but there is no water or the flow is too small.
Self-balancing wear-resistant multi-stage pump
Cause Analysis:
1. The flow channel is blocked, or the bottom valve is partially blocked;
2. The pump speed is lower than the specified value;
3. The total head of the system is higher than the design head of the pump;
4. Gas enters the pump;
5. The pump steering is wrong;
6. The parts are worn and the internal leakage is too large;
Solution:
1. Clean the flow channel or remove foreign matter in the bottom valve;
2. Increase the pump speed to increase the number of pump stages or reduce pipeline losses;
3. Block the air intake part;
4. Re-wiring the motor;
5. Replace worn parts.
C. Failure phenomenon: The current of the self-balancing wear-resistant multi-stage pump motor is too large.
Cause Analysis:
1. The total head of the system is much lower than the design head of the pump;
2. The pipeline is broken and running water;
3. The outlet gate valve is not closed when starting;
4. The pump shaft and the motor shaft are not concentric;
5. Friction between the rotating part and the fixed part;
6. Bearing wear;
7. The rotor is unbalanced, causing vibration;
8. The voltage is too low;
Solution:
1. Close the gate valve to adjust, or reduce the number of pump stages;
2. Stop the pump and deal with the pipeline;
3. Close the gate valve and restart;
4. Re-align to avoid system force acting on the pump;
5. Disassemble the pump and re-adjust;
6. Replace the bearing;
7. Disassemble the rotor for static and dynamic balance testing;
8. Increase the voltage.
D. Failure phenomenon: The stuffing box leaks too much, the stuffing heats up and smokes, and the packing life is short.
Cause Analysis:
1. The pump shaft and the motor shaft are not concentric;
2. The shaft is bent;
3. The shaft sleeve at the packing is damaged, or the packing is installed improperly, or the packing type is wrong;
4. There are impurities between the packing and the shaft sleeve;
Solution:
1. Re-alignment;
2. Disassemble and correct the shaft;
3. Grind or replace the shaft sleeve, or reinstall the packing, evenly compress it, or replace the packing;
4. Replace the packing.
E. Failure phenomenon: self-balancing wear-resistant multi-stage pump vibrates or is noisy.
Cause Analysis:
1. Cavitation occurs in the pump;
2. The flow channel is blocked, or the bottom valve is partially blocked;
3. The pipeline is broken and running water;
4. The outlet valve opens and starts;
5. The pump and motor shafts are not concentric, or the shaft is bent;
6. Insufficient foundation rigidity;
7. There is friction between the rotating part and the fixed part;
8. Impeller defect;
9. Too much or too little grease in the bearing;
10. Bearing wear or dirt inside;
Solution:
1. Reduce the geometric installation height of the pump and reduce the resistance of the suction pipe;
2. Clean the flow channel or clean the bottom valve;
3. Stop pump processing pipeline;
4. Close the gate valve and restart;
5. Re-align, or overhaul, or change the shaft;
6. Reinforce the foundation;
7. Disassemble and re-adjust the pump;
8. Replace the impeller;
9. Add proper amount of grease;
10. Replace or clean the bearings, and pay attention to sealed bearings.
F. Failure phenomenon: bearing heating.
Cause Analysis:
1. The pump shaft is not concentric with the motor shaft, or the shaft is bent;
2. Friction between rotating parts and fixed parts;
3. The bearing is damaged, or there is dirt or water in the bearing;
4. Too much or too much grease in the bearing;
Solution:
1. Re-align, or overhaul or change the shaft;
2. Disassemble and re-adjust the pump;
3. Add proper amount of grease;
4. Replace or clean the bearings, and pay attention to sealed bearings.
G. Trouble phenomenon: The joint surface leaks in the middle section and other places.
Cause Analysis:
1. Insufficient or uneven tightening force of the bolts on the bars;
2. The manufacturing accuracy (roughness, runout or perpendicularity) of the part does not meet the design requirements, or the residual stress causes the part to deform;
3. The bonding surface is unclean or damaged;
Solution:
1. Re-tighten the through bars;
2. Disassemble the pump for inspection;
3. Overhaul the joint surface.
