Analysis on the causes for 3 inch diameter submersible deep well pump not sending out water
Air exists in the inlet pipe and the pump body
1) The self-priming deep well pump is not filled with enough water before it starts. Sometimes it may seems like the pump is full enough with water as you see water spilling out from the air discharge hole. But you didn’t turn the pump shaft to exhaust all the air, leaving a small amount of air remaining in the inlet pipe or pump body.
2) The horizontal section of the inlet pipe connecting with the pump should run downward on a 0.5% slope in the direction contrary to the flow of water. The inlet of the pipe connecting with the deep well pump should be at the highest point, not completely horizontal. If the inlet pipe cocks, there will be air remaining in it, which will bring down the vacuum degree in water pipe and deep well pump, impacting suction.
3) The packing of single stage 3 inch diameter submersible deep well pump is worn out as a result of long term operation, or is too loose, leading to a large amount of water ejected out from the clearance between the packing and the pump shaft sheath. That will allow air to enter the pump through this clearance, impacting the lifting of water.
4) As the inlet pipe is always submerged under water, its wall will be corroded and hole. After the 3 inch diameter submersible deep well pump has started working, the water surface will keep dropping. When the holes are above water surface, air will enter the inlet pipe through them.
5) The bends of inlet pipe crack. Even tiny clearance at the connection between inlet pipe and water pump will be possible for air to enter the inlet pipe.
2) The horizontal section of the inlet pipe connecting with the pump should run downward on a 0.5% slope in the direction contrary to the flow of water. The inlet of the pipe connecting with the deep well pump should be at the highest point, not completely horizontal. If the inlet pipe cocks, there will be air remaining in it, which will bring down the vacuum degree in water pipe and deep well pump, impacting suction.
3) The packing of single stage 3 inch diameter submersible deep well pump is worn out as a result of long term operation, or is too loose, leading to a large amount of water ejected out from the clearance between the packing and the pump shaft sheath. That will allow air to enter the pump through this clearance, impacting the lifting of water.
4) As the inlet pipe is always submerged under water, its wall will be corroded and hole. After the 3 inch diameter submersible deep well pump has started working, the water surface will keep dropping. When the holes are above water surface, air will enter the inlet pipe through them.
5) The bends of inlet pipe crack. Even tiny clearance at the connection between inlet pipe and water pump will be possible for air to enter the inlet pipe.
The 3 inch diameter pump rotates at low speed
1) Human causes Some clients will drive the pump with another motor when the original motor breaks down. That will cause such consequences as small flow quantity, low head and even failure of lifting water.
2) Mechanical failures of the submersible pump itself The fasten screws on impellers and pump shaft become loose or the pump shaft is distorted and bent, causing displacement of the impellers or damage to shaft bearing. As a result, the impellers will rub against the pump body directly. All these are possible causes for the decrease of the rotation speed of the pump.
3) The motor is not well repaired. The motor is demagnetized because its windings are born out. If the number of coils of windings, the diameter of the wire or the way of wire connection is changed during maintenance, or the problems are not totally solved, the rotation speed of the water pump will also change.
2) Mechanical failures of the submersible pump itself The fasten screws on impellers and pump shaft become loose or the pump shaft is distorted and bent, causing displacement of the impellers or damage to shaft bearing. As a result, the impellers will rub against the pump body directly. All these are possible causes for the decrease of the rotation speed of the pump.
3) The motor is not well repaired. The motor is demagnetized because its windings are born out. If the number of coils of windings, the diameter of the wire or the way of wire connection is changed during maintenance, or the problems are not totally solved, the rotation speed of the water pump will also change.
No comments:
Post a Comment