Key points for using and selecting submersible pumps

The submersible pump is made according to the length of the container (generally 1 to 1.5m). The working part of the submersible pump is immersed in the liquid, and the axial force and radial force generated by the operation of the pump are supported by rolling bearings and sliding bearings respectively; therefore, the operation is quiet and noiseless. There is no liquid splashing in the shaft seal. There is a cooling system at the packaging, which can take away the heat with cooling water according to the temperature of the medium used by the user.

Key points for safe use of submersible pumps:
1. When purchasing a submersible pump, pay attention to the model, flow rate, and head. If the selected specifications are not appropriate, sufficient water output cannot be obtained, and the efficiency of the unit cannot be exerted. In addition, the direction of rotation of the motor must also be clarified. Some models of submersible pumps can produce water in both forward and reverse rotations, but the reverse water output is small and the current is large, which will damage the motor windings. In order to prevent electric shock caused by leakage when the submersible pump works underwater, a leakage protection switch should be installed.
2. When installing the submersible pump, the cable should be overhead and the power cord should not be too long. When the machine is launched, do not pull the cable hard to avoid breaking the power cord. Do not sink the submersible pump into the mud, otherwise it will cause poor heat dissipation and burn the electric
3. Try to avoid starting the machine at low voltage. The difference between the power supply voltage and the rated voltage should be 10%. If the voltage is too high, the motor will overheat and burn the windings. If the voltage is too low, the motor speed will decrease. If it is lower than 70% of the rated speed, the starting centrifugal switch will be closed, causing the starting winding to be energized for a long time, heating up and even burning the winding and capacitor. Do not switch the motor on and off frequently. This is because backflow will be generated when the electric pump stops running. If it is turned on immediately, the motor load will be started, resulting in excessive starting current and burning the winding.
4. Do not let the water pump run overloaded for a long time, and do not pump water with high sand content. The dehydration time of the electric pump cannot be too long to avoid overheating and burning of the motor. During the operation of the unit, the operator should always observe whether its working voltage and current are within the numerical range specified on the nameplate. If not, the motor should be stopped, the cause should be found and the fault should be eliminated.
5. Check the motor more often at ordinary times. If the lower cover is cracked, the rubber seal is damaged or failed, etc. It should be replaced or repaired in time to prevent water from seeping into the machine.

Selection method of submersible pump:
1. Flow rate is one of the important performance data of submersible pump, which is directly related to the production capacity and transportation capacity of the whole device. The selection of pump is based on the flow rate, taking into account the normal flow rate. When there is no large flow rate, 1.1 times the normal flow rate is usually taken as the flow rate.
2. The head required by the device system is another important performance indicator of the submersible pump. Generally, the lift after the margin is enlarged by 5%-10% is used to select the model.
3. The pipeline layout conditions of the submersible pump system refer to the liquid supply height, liquid supply distance and liquid supply direction, so as to calculate the system head and check the cavitation margin.
4. Liquid properties, including the name, physical properties, chemical properties and other properties of the liquid medium. Physical properties include temperature C, density D, viscosity U, solid particle diameter and gas content in the medium. This includes calculating the system head, effective cavitation margin and appropriate pump type. Chemical properties mainly refer to the chemical corrosiveness and toxicity of the liquid medium, which is an important basis for selecting submersible pump materials and shaft seal types.