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Six common faults of water pump and Solutions
Source:未知|Popularity:0|release date:2020-05-15 14:34:13
Common faults and solutions of water pump are explained by Sanchang pump as follows:
1. Unable to start
First, check the power supply: whether the connector is firmly connected; whether the switch contacts closely; whether the fuse is blown; whether the three-phase power supply is lack of equality. In case of open circuit, poor contact, fuse fusing and phase loss, the cause shall be found out and repaired in time. Secondly, check whether it is the mechanical failure of the pump itself. The common reasons are: the packing is too tight or the impeller and the pump body are blocked by debris; the pump shaft, bearing and leakage reducing ring are rusted; the pump shaft is seriously bent, etc. Troubleshooting: loosen the packing, dredge the water diversion channel; dismantle the pump body to remove debris and rust; dismantle the pump shaft for correction or replace it with a new one.
2. Auxiliary power motor overheated
There are four reasons. First, the power supply: the voltage is too high or too low. Under the specific load, if the voltage variation range is more than + 9% to - 5% of the rated value, the motor will overheat; if the three-phase voltage of the power supply is asymmetric, the imbalance degree between the three-phase voltage of the power supply is more than 5%, the winding will be overheated; if the phase loss operation, experience shows that more than 85% of the agricultural motor is burned due to the phase loss operation If yes, the motor shall be equipped with phase loss protection device. The second is the reason of water pump: the motor is overloaded for a long time, which causes the motor temperature to be too high; the motor is started too frequently and rated as short-time or intermittent working system to work continuously. The starting times shall be limited, the thermal protection shall be selected correctly and used according to the rated value on the motor. The third is the reason of the motor itself: the connection method is wrong, the delta shape is wrongly connected to the Y shape, which makes the temperature of the motor rise rapidly; the stator winding has inter phase short circuit, inter turn short circuit or local grounding, when the motor is light, it is locally overheated, and when it is serious, the insulation is burnt out; the squirrel cage rotor is broken or has defects, and the temperature of the iron core rises rapidly when the motor runs for 1 to 2 hours; if the ventilation system fails, it should be checked Check whether the fan is damaged, whether the rotation direction is correct, and whether the ventilation duct is blocked; whether the bearing is worn and the rotor is swept eccentrically makes the stator and rotor cores rub against each other to produce metal impact sound, and the core temperature rises rapidly, in serious cases, the motor smokes or even the coil is burnt. Fourth, the working environment: the motor winding is affected by damp or dust, oil and other adhesion on the winding, resulting in reduced insulation. The insulation resistance of the motor shall be measured, cleaned and dried; the ambient temperature is too high. When the ambient temperature is over 35 ℃, the air inlet temperature is high, which will cause the motor temperature to be too high. Therefore, it is necessary to improve its working environment. Such as setting up awning and sunshade. Note: in case of failure due to electricity, electricians with professional qualification certificate shall be invited for maintenance. People with half knowledge shall not conduct maintenance blindly to prevent personal injury accidents.
3. Water pump heating
Causes: the bearing is damaged; the clearance between the rolling bearing or bracket cover is too small; the pump shaft is bent or the two shafts are not concentric; the tape is too tight; the oil is insufficient or the oil quality is not good; the balance hole on the impeller is blocked and the impeller is out of balance, which increases the thrust to one side. Troubleshooting: replace the bearing; remove the back cover and add gasket between the bracket and the bearing seat; investigate the concentricity of the pump shaft or adjust the concentricity of the two shafts; properly loosen the tightness of the tape; add clean butter, which accounts for about 60% of the clearance in the bearing; remove the blockage in the balance hole.
4. Insufficient flow
This is because: the power speed is not matched or the belt slips, making the speed low; the installation angle of the axial flow pump blade is too small; the head is insufficient, the pipeline is too long or the pipeline has a right angle bend; the suction head is too high; the bottom valve, pipeline and impeller are partially blocked or the impeller is damaged; the water leakage of the outlet pipe is serious. Troubleshooting: restore the rated speed, remove the belt oil dirt, adjust the belt tightness; adjust the blade angle, reduce the installation position of the water pump, shorten the pipeline or change the curvature of the pipeline; seal the air leakage of the water pump, compress the packing; remove the blockage, replace the impeller; replace the leakage reduction ring, and block the water leakage.
5. Unable to absorb water
The reason is that there is air in the pump body or air accumulated in the water inlet pipe, or the bottom valve is not closed tightly, the filling of the vacuum pump is seriously leaking, and the gate valve or flap valve is not closed tightly. Troubleshooting: first, put the water pressure up, and then fill the pump body with water, and then start the machine. At the same time, check whether the check valve is tight and whether the pipeline and joint have air leakage. If air leakage is found, apply lubricating oil or blending paint on the joint after disassembly, and tighten the screws. Check the oil seal ring of the water pump shaft. If it is seriously worn, replace it with a new one. Water or air leaks in the pipeline. The nut may not be tightened tightly during installation. If the leakage is not serious, the place with air or water leakage can be coated with cement, or the cement slurry mixed with asphalt oil can be coated. Temporary repairs can be done with wet mud or soft soap. If there is water leakage at the joint, the nut can be tightened with a wrench. If there is serious water leakage, it is necessary to dismantle it again and replace the cracked pipe; reduce the lift and press the pipe orifice of the water pump into the water for 0.5m.
6. Violent vibration
The main reasons are as follows: the electric rotor is unbalanced; the coupling is not well combined; the bearing is worn and bent; the rotating parts are loose and cracked; the pipeline support is not firm and so on. It can be adjusted, repaired, reinforced, straightened and replaced respectively.
The above situation is the common cause of pump failure, not all of them. In practice, to deal with the failure, we should follow the principle of "first outside, then inside", and never operate blindly.
1. Unable to start
First, check the power supply: whether the connector is firmly connected; whether the switch contacts closely; whether the fuse is blown; whether the three-phase power supply is lack of equality. In case of open circuit, poor contact, fuse fusing and phase loss, the cause shall be found out and repaired in time. Secondly, check whether it is the mechanical failure of the pump itself. The common reasons are: the packing is too tight or the impeller and the pump body are blocked by debris; the pump shaft, bearing and leakage reducing ring are rusted; the pump shaft is seriously bent, etc. Troubleshooting: loosen the packing, dredge the water diversion channel; dismantle the pump body to remove debris and rust; dismantle the pump shaft for correction or replace it with a new one.
2. Auxiliary power motor overheated
There are four reasons. First, the power supply: the voltage is too high or too low. Under the specific load, if the voltage variation range is more than + 9% to - 5% of the rated value, the motor will overheat; if the three-phase voltage of the power supply is asymmetric, the imbalance degree between the three-phase voltage of the power supply is more than 5%, the winding will be overheated; if the phase loss operation, experience shows that more than 85% of the agricultural motor is burned due to the phase loss operation If yes, the motor shall be equipped with phase loss protection device. The second is the reason of water pump: the motor is overloaded for a long time, which causes the motor temperature to be too high; the motor is started too frequently and rated as short-time or intermittent working system to work continuously. The starting times shall be limited, the thermal protection shall be selected correctly and used according to the rated value on the motor. The third is the reason of the motor itself: the connection method is wrong, the delta shape is wrongly connected to the Y shape, which makes the temperature of the motor rise rapidly; the stator winding has inter phase short circuit, inter turn short circuit or local grounding, when the motor is light, it is locally overheated, and when it is serious, the insulation is burnt out; the squirrel cage rotor is broken or has defects, and the temperature of the iron core rises rapidly when the motor runs for 1 to 2 hours; if the ventilation system fails, it should be checked Check whether the fan is damaged, whether the rotation direction is correct, and whether the ventilation duct is blocked; whether the bearing is worn and the rotor is swept eccentrically makes the stator and rotor cores rub against each other to produce metal impact sound, and the core temperature rises rapidly, in serious cases, the motor smokes or even the coil is burnt. Fourth, the working environment: the motor winding is affected by damp or dust, oil and other adhesion on the winding, resulting in reduced insulation. The insulation resistance of the motor shall be measured, cleaned and dried; the ambient temperature is too high. When the ambient temperature is over 35 ℃, the air inlet temperature is high, which will cause the motor temperature to be too high. Therefore, it is necessary to improve its working environment. Such as setting up awning and sunshade. Note: in case of failure due to electricity, electricians with professional qualification certificate shall be invited for maintenance. People with half knowledge shall not conduct maintenance blindly to prevent personal injury accidents.
3. Water pump heating
Causes: the bearing is damaged; the clearance between the rolling bearing or bracket cover is too small; the pump shaft is bent or the two shafts are not concentric; the tape is too tight; the oil is insufficient or the oil quality is not good; the balance hole on the impeller is blocked and the impeller is out of balance, which increases the thrust to one side. Troubleshooting: replace the bearing; remove the back cover and add gasket between the bracket and the bearing seat; investigate the concentricity of the pump shaft or adjust the concentricity of the two shafts; properly loosen the tightness of the tape; add clean butter, which accounts for about 60% of the clearance in the bearing; remove the blockage in the balance hole.
4. Insufficient flow
This is because: the power speed is not matched or the belt slips, making the speed low; the installation angle of the axial flow pump blade is too small; the head is insufficient, the pipeline is too long or the pipeline has a right angle bend; the suction head is too high; the bottom valve, pipeline and impeller are partially blocked or the impeller is damaged; the water leakage of the outlet pipe is serious. Troubleshooting: restore the rated speed, remove the belt oil dirt, adjust the belt tightness; adjust the blade angle, reduce the installation position of the water pump, shorten the pipeline or change the curvature of the pipeline; seal the air leakage of the water pump, compress the packing; remove the blockage, replace the impeller; replace the leakage reduction ring, and block the water leakage.
5. Unable to absorb water
The reason is that there is air in the pump body or air accumulated in the water inlet pipe, or the bottom valve is not closed tightly, the filling of the vacuum pump is seriously leaking, and the gate valve or flap valve is not closed tightly. Troubleshooting: first, put the water pressure up, and then fill the pump body with water, and then start the machine. At the same time, check whether the check valve is tight and whether the pipeline and joint have air leakage. If air leakage is found, apply lubricating oil or blending paint on the joint after disassembly, and tighten the screws. Check the oil seal ring of the water pump shaft. If it is seriously worn, replace it with a new one. Water or air leaks in the pipeline. The nut may not be tightened tightly during installation. If the leakage is not serious, the place with air or water leakage can be coated with cement, or the cement slurry mixed with asphalt oil can be coated. Temporary repairs can be done with wet mud or soft soap. If there is water leakage at the joint, the nut can be tightened with a wrench. If there is serious water leakage, it is necessary to dismantle it again and replace the cracked pipe; reduce the lift and press the pipe orifice of the water pump into the water for 0.5m.
6. Violent vibration
The main reasons are as follows: the electric rotor is unbalanced; the coupling is not well combined; the bearing is worn and bent; the rotating parts are loose and cracked; the pipeline support is not firm and so on. It can be adjusted, repaired, reinforced, straightened and replaced respectively.
The above situation is the common cause of pump failure, not all of them. In practice, to deal with the failure, we should follow the principle of "first outside, then inside", and never operate blindly.