[Methanol Technical Version] Equipment Questions, July 24

Common faults of water pumps include: no water supply, insufficient or interrupted water output, high starting load, vaporization, and so on.

Symptom 1: The water pump will not start. First, check the power supply: ensure that the connections are secure； Are the switch contacts secure? ； Is the fuse blown? ； Check whether there is a phase imbalance in the three-phase power supply. In the event of an open circuit, poor contact, blown fuse, or missing phase, the cause should be identified and repairs carried out promptly. Secondly: check whether it is a mechanical fault of the water pump itself. Common causes: The packing is too tight, or debris has accumulated between the impeller and the pump casing, causing a blockage ； The pump shaft, bearings, and leak reduction rings are rusted ； Severe bending of the pump shaft, etc. Exclusion method: Relax the filler and clear the water guide channel ； Disassemble the pump body to remove debris and rust ； Remove the pump shaft to correct it or replace it with a new one. Condition 2: Insufficient flow. Cause: Usually due to air leakage in the suction pipe or the bottom valve ； The water inlet is blocked ； The submersible valve is not deep enough in the water ； The water pump speed is too low ； The sealing ring or impeller is excessively worn ； Excessive water absorption height, etc. Exclusion method: Check the suction pipe and bottom valve to block the source of air leakage ； Clear the silt or blockages at the water inlet ； The submersed depth of the bottom valve must be more than 1.5 times the diameter of the inlet pipe; increase the submersed depth of the bottom valve ； Check the power supply voltage, increase the pump speed, and replace the seal ring or impeller ； Lower the installation position of the water pump, or replace it with a high-head water pump. Symptom 3: Inability to draw in water. Causes: Air in the pump chamber or air accumulation in the water inlet pipe, a poorly sealed bottom valve, insufficient water filling, severe leakage from the vacuum pump’s packing, or poorly closed gate valves or check valves. Exclusion method: 1. First increase the water pressure, then fill the pump body with water, and finally turn it on. At the same time, check whether the check valve is airtight and whether there are any air leaks in the pipes and connections; if leaks are found, disassemble them, apply lubricant or sealant to the connections, and tighten the screws. 2. Check the oil seal ring of the water pump shaft; if it is severely worn, replace it with a new one. 3. Leaks in the pipes or air leaks. Perhaps the nut wasn’t tightened properly during installation. If the leakage is not severe, cement can be applied to the area where air or water is leaking, or a cement slurry mixed with asphalt oil can be used. For temporary repairs, some wet mud or soft soap can be applied. If there is leakage at the joint, the nut can be tightened using a wrench; if the leakage is severe, the assembly must be disassembled again and the cracked pipe replaced ； Reduce the head by submerging the pump outlet 0.5m underwater. Symptom 4: The water pump does not deliver water. Cause: The pump body and suction pipe are not filled with water ； The dynamic water level is below the pump’s filter pipe ； Rupture of the suction pipe, etc. Exclusion method: Rule out bottom valve failure, fill with water ； Lower the installation position of the water pump so that the filter pipe is below the dynamic water level, or wait until the dynamic water level rises above the filter pipe before pumping water ； Repair or replace the suction pipe. Symptom 5: Severe vibration or noise from the pump body. Cause: The pump is not installed properly or is installed too high ； Damage to the motor ball bearing ； The water pump shaft is bent, or it is not aligned or parallel to the motor shaft. Solution: Securely install the water pump or reduce its installation height ； Replace the motor ball bearing ； Correct the bent pump shaft or adjust the relative position of the pump and the motor. Symptom 6: Excessive power consumption. Cause: The pump speed is too high ； The water pump shaft is bent, or the water pump shaft is not aligned or parallel to the motor shaft ； The head of the water pump selected is not appropriate ； The water pump is sucking in sediment or blockages ； Damage to the motor’s ball bearings, etc. Solution: Check the circuit voltage and reduce the pump speed ； Correct the main shaft of the water pump or adjust the relative position between the water pump and the motor ； Choose a pump with an appropriate head ； Remove sediment or blockages ； Replace the ball bearings of the motor. Symptom 7: Overheating of the drive shaft or motor bearings. Causes: Lack of lubricant or damaged bearings, etc. Solution: Add lubricant or replace the bearing. The above situations are common causes of the \"problems\" with water pumps, but they are not the only causes. When dealing with such faults in practice, it is necessary to conduct a thorough analysis based on the specific situation, following the principle of addressing external issues first before dealing with internal ones; blind actions should be avoided.

No water supply, insufficient or interrupted water output, excessive starting load, vaporization, etc.

1. The water pump will not start. II. Insufficient flow rate III. Inability to draw water in IV. Pump does not discharge water V. Severe vibration or noise from the pump body VI. Excessive power consumption VII. Overheating of the drive shaft or motor bearings

1. The water pump will not start. II. Insufficient flow rate III. Inability to draw water in IV. The water pump does not discharge water V. Severe vibration or noise from the pump body VI. Excessive power consumption VII. Overheating of the drive shaft or motor bearings

No water supply, failure to start, low flow rate, vibration or abnormal noises, bearing overheating, water leakage, etc

The water pump will not start； Insufficient traffic ； Can’t draw in water ； The water pump is not delivering water ； Severe vibration or noise from the pump body ； Excessive power consumption ； Overheating of the drive shaft or motor bearings

　1. Overheating of the auxiliary drive motor; 2. Insufficient flow rate; 3. Water pump overheating; 4. Failure to start; 5. Inability to draw water in; 6. Severe vibration

No water supply, insufficient or interrupted water output, excessive starting load, vaporization, etc.

No water supply, insufficient or interrupted water output, high starting load, vaporization, and so on.