Mastering These Points Makes Installation and Use of Self-priming Centrifugal Pumps No Longer Difficult!

Self-priming centrifugal pump is a horizontal structure, with the pump and the motor integrated, beautiful appearance, and occupying less space. Compared with ordinary self-priming pumps, its area can be reduced by 30%. If an IP54 outdoor motor is used, there is no need for a pump room, and it can be used outdoors.

When the self-priming centrifugal pump is directly connected to the motor for transmission, attention should be paid to the coaxiality of the pump shaft and the motor output. The accuracy of the installation of the self-priming centrifugal pump has a great influence on its smooth operation and service life. Therefore, the installation and calibration must be carefully done.

The coupling of the self-priming centrifugal pump must be tightened with a spiral and the nut must be locked to prevent the nut from loosening. Otherwise, it may cause impeller running and mechanical failures.

In order to maintain a certain amount of storage liquid inside the self-priming centrifugal pump, so as to achieve better self-priming ability and prevent dry friction of the mechanical seal, the inlet of the pump must be higher than the pump shaft centerline.

The installation of the suction pipeline of the self-priming centrifugal pump should pay attention to:

• The installation height of the suction inlet should not exceed 3.5 meters. When conditions permit, the installation height of the suction inlet should be as low as possible below the artificially-constructed water storage level of the water tank, and the length of the suction pipe should be shortened as much as possible. It is helpful to shorten the self-priming time and improve the self-priming function.

•  Valves and flanges in the suction pipeline should be strictly prevented from air leakage or liquid seepage, and air leakage in the suction pipeline is not allowed.
  

• It is necessary to prevent the self-priming centrifugal pump from sucking in solid debris, and a filter should be installed on the suction pipeline. The effective flow area of the filter should be 2-3 times the cross-sectional area of the suction pipe, and the filter should be inspected regularly.
  

• The suction pipeline and discharge pipeline should have their own supports, and the self-priming centrifugal pump should not bear the load of the pipeline itself.
  

During installation, the static grounding resistance of the self-priming centrifugal pump and pipeline should meet the specified requirements.

It should be strictly checked during installation whether the static grounding resistance of the pump shell and pipeline of the self-priming centrifugal pump meet the specified requirements.

Correct and align the installation clearance and coaxiality of the self-priming centrifugal pump coupling and motor coupling. The allowable deviation of non-coaxiality is 0.1mm. The height difference between the pump shaft and the motor shaft can be adjusted by adding copper or iron sheets to the bottom feet.

After the self-priming centrifugal pump unit has been in actual operation for 3-4 hours, a final check should be performed. If there are no adverse phenomena, the installation can be considered as completed. When running the test, the bearing temperature should be checked, and the temperature of the bearing should not exceed 70°C.

The cooling water joint for the bearing housing of the self-priming centrifugal pump should be equipped with a joint for a Φ12 rubber or plastic tube. The thread size is M12×1.25.

If a one-way valve is installed on the outlet pipeline of the self-priming centrifugal pump and it cannot smoothly discharge air during the self-priming process, a small discharge pipe and valve should be added to the outlet of the pump.