Reasons why water does not come out of a multistage pump during operation

Multistage pumps are industrial pumps, widely used, multistage pumps also have several series, such as D type, DG type, DF type, DM type these models of multistage pumps belong to the horizontal multistage pump, DL type, DLR type, GDL type these belong to the vertical multistage pump, multistage pumps in the use of the process of more or less will appear some common failures, such as balance plate wear, the pump does not start after the water or start no response, the pump The bearings get hot and other problems.

Multi-stage pump running on the water or on the small amount of water causes

A, multi-stage pump speed is too low

1、The human factor

On the one hand, due to the damage of the power machine, on the arbitrary collocation of a power machine, the result is that the flow rate of the pump is smaller than the design flow rate, head is also lower than the design head, there may even lead to the consequences of the pump directly not on the water and so on.

2, power machine maintenance is not working

Power motor winding burned, resulting in the loss of motor magnetism, due to the maintenance of the motor winding turns, wire diameter, wiring and other changes in the method, or not completely repair the motor, will likely lead to changes in the pump motor speed.

3、Mechanical failure itself

Water pump impeller and pump shaft between the nut loose or multi-stage pump shaft deformation bending, will likely cause multi-stage pump impeller displacement and pump bearing damage, reduce the speed of the pump, affect the flow head of the pump.

Second, multi-stage pump into the water pipe and pump body with air

1, multi-stage pump into the water pipe for a long time in the pump medium, there has been corrosion holes phenomenon, when the multi-stage pump to resume work, these holes exposed to the media outside, air can then enter the water pipe through these holes.

2, multi-stage water pump packing due to long time use has been worn more serious, or filling material when the pressure is too loose, resulting in a large amount of water from the packing or pump shaft sleeve gap out, the outside space also through these gaps into the interior of the pump, affecting the multi-stage water pump lifting function.

3, multi-stage water pump and the horizontal section of the water pump inlet pipe against the direction of water flow should be connected to the other end of the water pump inlet pipe with a descending slope of 0. 5% or more, it cannot be designed to be completely horizontal, if one end of the inlet pipe is cocked upwards, there will be air entering inside the inlet pipe, reducing the vacuum of the water pump inside the pipe and affecting the suction function of the multi-stage water pump.

4, multi-stage pumps are not filled with enough medium in the pump body before starting, although sometimes it looks like the medium has overflowed from the pump air hole, but at this time the pump does not rotate and run to discharge the air in the pump, resulting in some space remaining in the pump body or inlet pipe.