Centrifugal Pump Operation and Maintenance

The following five points should be noted when operating a multistage centrifugal pump:

1. When the balance mechanism relies on an internal balancing device to balance the axial force, if the balance device has liquid flowing out, the balance liquid is led to the suction section through a balance water pipe or a short pipe is installed at the balance chamber, and the balance liquid flows out of the pump through the short pipe. To ensure the normal operation of the centrifugal pump, the balance water pipe must never be blocked.

1. The temperature rise of the bearings reflects the assembly quality of the centrifugal pump. The temperature rise of the bearings should not exceed 35℃ above the ambient temperature, and the maximum temperature should not exceed 75℃. When the bearing temperature is too high, the bearing cooling cavity and the pump bracket should be cooled by water.

1. The rotor of the centrifugal pump has a certain amount of axial movement during operation, and the gap between the end faces of the pump and the motor couplings should be ensured.

1. During the operation of the centrifugal pump, the impeller, sealing ring, guide vane sleeve, and balance plate should be checked regularly. If the wear of the shaft sleeve is too large, it should be replaced in time.

1. The bearing part is cooled by external industrial water or tap water, and the cooling water for the filling box cooling cavity and the pump bracket can be tap water. The cooling water pressure is 0.15~0.25Mpa. The flushing liquid pressure at the mechanical seal cover is higher than the inlet pressure by 0.1～0.15 Mpa.

Centrifugal Pump Maintenance

1. The operator should regularly keep a record of the equipment's operation. By observing the operation frequently, the operator can detect faults in time and eliminate them promptly.

1. When the bearing is lubricated with grease, the lubricating grease must be replaced for the first time after one month of cumulative use under normal circumstances, and then replaced every six months of cumulative use.

1. The normal operating temperature of the bearings is within the range of 40～60℃. This temperature is measured on the bearing body. If the temperature remains unchanged, it is also feasible to slightly exceed the above range.

1. If the bearing temperature exceeds 80℃ (if there is no thermometer, touch the bearing seat with your hand, if it feels hot and cannot stay, it means the temperature is too high), it should be checked.

1. The packing seal should have a small amount of leakage, and the leaking water should be in droplets.

1. When the packing gland cannot be adjusted anymore or the packing has rotted and the nut cannot reduce the leakage, the packing should be replaced. When replacing the packing, it should be noted that the joints of adjacent two packings must be staggered by 120°.

1. Check all measuring instruments, especially the inlet and outlet pressure gauges, to see if they indicate normal operating conditions.

Translation Accuracy Disclaimer: Please note that this translation is provided for informational purposes only and should not be relied upon as an official or accurate translation of the original text.