Points to note for centrifugal water pumps

Precautions for centrifugal pumps

(1) It is strictly forbidden to start or adjust the centrifugal pump by closing the inlet valve.

(2) The operation shall not exceed 3 minutes under the condition of closing the outlet valve.

(3) If the centrifugal pump is evacuated or semi-evacuated, it should be adjusted or handled immediately.

(4) It is strictly forbidden to operate at over-temperature, over-pressure or overload.

(5) When the hot oil pump is preheating the pump body, if the vent valve is used to evacuate, the vent valve opening should be strictly controlled to avoid burns and fire.

(6) The temperature of the sliding bearing is not more than 65℃, and the temperature of the rolling bearing is not more than 70℃.

(7) The operation is balanced, without noise, the sealing oil, cooling water and lubricating oil systems work normally, and there is no dripping in the auxiliary pipelines.

(8) The current shall not exceed the rated value.

(9) The flow rate and pressure are stable, reaching the value indicated on the nameplate or meeting production needs.

(10) The seal leakage shall not exceed the following requirements:

Mechanical seal: 10 drops/min for light oil and 5 drops/min for heavy oil.

Soft packing seal: 20 drops/min of light oil, 10 drops/min of heavy oil.

Maintenance of centrifugal pump

Operating pump

(1) Check whether the pump outlet pressure is sufficient, whether the pressure and current pointers are shaking or changing, check the pump load, whether there is any vacuum, and check whether the current indication exceeds the rated current. Any abnormal situation found should be reported to the operator and the team leader in time for timely handling.

(2) Check whether the pump oil tank temperature and the temperature of the motor bearing, housing, cable head, and junction box are normal. The bearing temperature shall not exceed 65℃.

(3) Check the vibration and sound of each part of the pump, and whether the parts and anchor screws of each part are loose.

(4) Check the leakage of the end face seal and maintain the appropriate sealing oil pressure.

(5) Check whether the cooling water system is unobstructed, the return water temperature of the Gland cooling water and the oil tank, and the pump seat cooling water, and adjust the appropriate amount of cooling water. If the water quality is too dirty or the water flow is not smooth, it should be handled in time.

(6) Check the oil throwing condition, oil quality (such as whether it contains water emulsification, oxidized colloid, impurities, metal powder and blackening), liquid level and oil temperature in the oil tank. Adhere to the three-level filtration and maintenance system of lubricating oil. If the liquid level is too low, add oil in time. If the oil deteriorates, change the oil in time.

(7) It is strictly forbidden to evacuate the pump for a long time. It is strictly forbidden to operate the pump for a long time at the minimum allowable flow rate (or close the outlet valve).

Spare pump

(1) Adhere to the regular turning maintenance system of the spare pump.

(2) Adhere to the regular switching maintenance system of the spare pump.

(3) Take advantage of the downtime opportunity to do minor repairs and maintenance of the spare pump (such as plugging leaks, replacing the cooling water rubber hose, tightening the water baffle, replacing the oil mark, small valve or pressure gauge).

(4) Take advantage of the downtime opportunity to thoroughly clean the dirty oil tank and replace it with qualified oil.

(5) Check the preheating condition of the preheating pump and do a good job of normal preheating of the spare pump.

(6) Dehydrate the standby pump.

(7) In winter, protect the standby pump from freezing and condensation.

(8) Keep the standby pump in good standby condition at all times.