The structure of the pipeline multi-stage centrifugal pump is mainly composed of: low pressure suction section (feed pipe, feed chamber); pump body (volute, guide wing, anti-wear ring); high pressure output end (pump head); balance device (balance pipe, Balance plate, balance disc); sealing device (packing seal, mechanical seal); pump shaft (shaft sleeve, impeller, positioning key, bearing).
Auxiliary devices: brackets, bases, couplings, motors, filters, etc.
Fault judgment and elimination phenomenon: After the pump is started, the pump pressure drops and the pump does not flow up.
The main reasons of pipeline multistage centrifugal pump:
Incomplete venting and air in the pump;
The filter or the oil inlet line is blocked (the oil flow is not smooth), and the inlet of the primary impeller is blocked;
Oil temperature is too low or too high;.
The liquid level (pressure) of the large tank or buffer tank is too low;
The balance device is seriously worn (the balance pipe is blocked or caused by improper operation
The low-pressure end of the centrifugal pump is not tightly sealed, and the leakage causes the air to enter the pump
Approach:
Re-vent until the liquid naturally flows out from the vent valve at the output end;
Clean the filter or check the diameter of the oil inlet line;
It is appropriate to control the oil delivery temperature between 450C and 500C;
Check the oil tank and buffer tank level and pressure;
Check the balancing device (open to check if necessary);
Check and replace the low-pressure end seal of the centrifugal pump or adjust the cap screw
Always check the bearing temperature, it should not be higher than the ambient temperature 35 ℃, rolling shaft. The higher temperature of the bearing shall not exceed 75℃; the higher temperature of the sliding bearing shall not exceed 65℃. Check the motor temperature rise frequently.