Introduction to the Pump Structure and Instructions for Use

Author:Site Editor     Publish Time: 2020-11-16      Origin:Site

Schematic diagram of a cross-sectional structure

pump cross-sectional structure

Pump three-dimensional structure diagram

pump three-dimensional structure diagram

Instructions for use of water pump

(1) The pump arrives at the engineering site after long-distance transportation. Before installation, check whether the parts of the whole machine are intact, the fasteners should be tightened, and the concentricity of the pump shaft and the motor shaft should be checked. If there is any displacement, it should be corrected.

(2) When transporting, the lifting ring on the pump body and the motor should be used as the focus point, and the lifting should be carried out gently, and there should be no big vibration or impact.

(3) The pump should be installed in a bright, spacious, and easy-to-maintain place, and the foundation should be flat.

(4) The diameter of the inlet and outlet pipelines cannot be smaller than the inner diameter of the inlet and outlet of the pump. In order to reduce the flow resistance of the pipeline and improve the transmission efficiency, the piping is recommended to be one level larger than the pump inlet and outlet.

(5) The inlet and outlet pipelines should be cleaned up, and a gravity support system should be installed. The pump cannot bear the weight of the pipeline, otherwise, it will be easily damaged.

(6) To facilitate maintenance and control, valves should be installed in the inlet and outlet pipelines of the pump.

(7) A compensator, also known as a flexible pipe joint, should be installed at the inlet and outlet of the pump. Its main function is to compensate for the stress caused by stretching, squeezing, and twisting of the infusion pipeline due to thermal expansion, contraction, or start-up vibration, thereby improving the detachability and safety performance of the equipment.

(8) For posts with a long (high) outlet pipeline distance, a check valve should be installed near the outlet of the pump to prevent the outlet high-pressure water hammer from damaging the pump during the shutdown.

(9) It is recommended to tighten the connecting bolts between the inlet and outlet of the pump and the pipeline first, and then tighten the anchor bolts of the pump to prevent the pump from being damaged by tensile stress when connecting the pipeline.

(10) During the installation of the pump, the coupling should be frequently rotated by hand to check whether there are any friction and collision noise in the pump.

(11) The inlet of the pump should be as close as possible to the liquid source. It is recommended to use the backflow condition, and the suction condition needs to be equipped with a siphon barrel. The installation methods for two common working conditions are as follows:


The installation method of the pump and pipeline for the back irrigation project (the liquid position is higher than the inlet of the pump).


The installation method of the pump, pipeline, and siphon barrel for the suction project (liquid position is lower than the inlet of the pump).

(12) As shown in the figure above, the suction working condition should minimize the hydraulic loss of the inlet pipeline, and no elbows less than 90°C should be installed, and no more than 2 elbows should be installed at 90°C. The pump inlet should be equipped with a filter to prevent large impurities block the inlet; the inlet pipe connecting bolts should be evenly tightened diagonally to prevent air leakage; the bottom of the siphon barrel should be provided with a base for load-bearing, and must not be installed in the air. One pump is equipped with a barrel, and multiple pumps cannot share a siphon barrel at the same time. If the spare pump shares the siphon barrel, a valve should be installed before the pump inlet.

Check before the operation

 (1) Before the operation, the coupling should be turned by hand to check whether the operation is flexible and whether there is abnormal noise. Abnormal conditions should be eliminated first.

(2) Check whether the running direction of the pump is consistent with the marked arrow. When checking the rotation of the motor, do not connect the coupling to prevent damage to the impeller and pump body from the motor reverse rotation.

(3) Check whether the position of the lubricating oil (CD40# diesel engine oil) is near the marking line from the oil mirror hole on the bearing seat. If it is too much, let it go, if it is too little, add some.

(4) Check the flow and pressure value of the sealed cooling water (see the requirements of the seal structure diagram and introduction section). Too high cooling water pressure may cause cooling water leakage and affect the service life of the mechanical seal.

(5) For suction conditions, the siphon barrel needs to be filled and the inlet pipeline and the siphon barrel must be sealed and airtight. The vertical distance H from the liquid level in the tank to the pump inlet should not exceed 2m (recommended within 1m, the shorter the better), otherwise, it may not be able to suck up, and will affect the service life of the pump.


(1) Open the inlet valve to let the liquid flow into the pump cavity.

(2) Connect the sealed cooling water.

(3) Turn on the power supply.

(4) Open the outlet valve in time (to avoid prolonged pressure operation) and adjust to the rated flow and head (adjustment with imported valves is strictly prohibited).


(1) If there are abnormal noises or other faults in the operation of the pump, stop and check immediately, and then continue to run after the fault is eliminated.

(2) Always check the temperature rise of the pump and motor. The temperature rise of the bearing should not exceed 40℃, and the limit temperature should not exceed 90℃. The maximum temperature rise of the motor is 90℃, and the limit temperature should not exceed 130℃.

(3) When the motor is overcurrent, the outlet valve should be closed to reduce the flow rate to prevent damage to the motor due to long-term overcurrent operation.

(4) The sealed cooling water cannot be interrupted during pump operation. The ceramic shaft sleeve of the K-type dynamic seal should be strictly prevented from encountering cold water after heating up, to avoid cracking due to sudden temperature drop.

(5) During pump operation, it is necessary to strictly prevent the pump cavity from running without liquid (such as the liquid in the tank has been evacuated, the inlet pipe is blocked, the low-level pool cannot be sucked up, etc.), and the empty running should not exceed 3 minutes when the cooling water is connected. Otherwise, it will burn the internal parts of the pump. It is strictly forbidden to continue using the pump immediately after it is running dry, and it should be used after the pump and the sealing parts have cooled down.

(6) The operation of the pump when the outlet valve is closed is called the pressing operation state. The pressing operation time of the plastic-lined pump should be as short as possible. The normal temperature medium should not exceed 5 minutes, and the high-temperature medium should not exceed 2 minutes.

Stop the pump

(1) Close the outlet valve (to prevent the water hammer from impacting the impeller due to the backward flow of the liquid in the outlet pipe, and the pump reverses to cause the impeller to loosen).

(2) Cut off the power supply.

(3) Close the inlet valve and seal the cooling water.


(1) Regularly check the oil level of the lubricating oil in the bearing housing, and replace the lubricating oil regularly (generally every six months).

(2) Keep the outside of the pump and the environment clean. When rinsing with water, prevent the motor from getting damp. After rinsing, use a cloth to clean the watermarks on the pump.

(3) For working conditions with high solid content or easy crystallization, clean water should be used to flush the pipeline and pump cavity before stopping the pump to prevent blockage caused by sediment or crystallization.

(4) The liquid may freeze in a low-temperature environment. After stopping the pump, empty the liquid in the pump cavity to prevent freezing and cracking. If there is icing, water can be heated to defrost if necessary, and then start the pump until the coupling can be flexibly rotated by hand.

(5) For pumps that have been out of service for a long time, in addition to venting the corrosive liquid in the pump, the pump body (especially the sealing parts) must be rinsed with clean water. Finally, seal the pump inlet and outlet and keep them properly.

(6) When using the siphon bucket, check the liquid stored in the siphon bucket regularly, and fill it up if there is any deficiency.


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