The reasons why the submersible pump often has insufficient flow or no water during operation and how to deal with it:
(1) The installation height of the water pump is too high, so that the impeller immersion depth is not enough, resulting in a decrease in the water output of the water pump; the allowable deviation of the installation elevation of the control pump cannot be arbitrarily expanded.
(2) The direction of rotation of the water pump is opposite. Before the test run of the water pump, the motor should be idling, and the direction of rotation should be checked to make it consistent with the water pump; if the above situation occurs during use, it should be checked whether the phase sequence of the power supply has changed.
(3) The outlet valve cannot be opened. Check valves and perform valve maintenance frequently.
(4) The water outlet pipeline is not smooth or the impeller is blocked. Clear blockages in pipelines and impellers, and often salvage debris in the reservoir.
(5) The wear ring at the lower end of the water pump is seriously worn or blocked by debris. Clean up debris or replace wear rings.
(6) The density of the pumped liquid is too high or the viscosity is too high. Find the causes of changes in water quality and manage them.
(7) The impeller falls off or is damaged. Reinforce or replace impeller.
(8) When multiple pumps share the pipeline output, there is no one-way valve installed or the one-way valve is not tightly sealed. Install or replace the one-way valve after checking the cause.
The operation of the submersible pump has abnormal vibration and instability. The main reasons are:
(1) The anchor bolts of the pump base are not tightened or loose; tighten all the anchor bolts evenly
(2) There is no independent support for the water outlet pipeline, and the vibration of the pipeline affects the pump; independent and stable supports are provided for the water outlet pipeline of the pump, and the flange of the water outlet pipe of the pump is not allowed to bear the load.
(3) The quality of the impeller is unbalanced or even damaged or the installation is loose; repair or replace the impeller
(4) The upper and lower bearings of the water pump are damaged; replace the upper and lower bearings of the water pump.
The main reasons for motor overload or over temperature caused by excessive current of submersible pump:
(1) The working voltage is too low or too high; check the power supply voltage and adjust the transmission voltage.
(2) There are moving and static parts inside the water pump or the impeller and the sealing ring rubbing; judge the position of the friction parts and eliminate the fault.
(3) The low lift and large flow cause the power of the motor to be inconsistent with the characteristics of the pump; adjust the valve to reduce the flow so that the power of the motor matches the pump.
(4) The pumped density or viscosity is high; check the reasons for the change of water quality and change the working conditions of the pump
(5) The bearing is damaged; replace the bearings at both ends of the motor
The main reasons and treatment methods for the low insulation resistance of submersible pumps:
(1) When the power cord is installed, the end is immersed in water or the power cord and signal line are damaged, causing water ingress; replace the cable or signal line, and dry the motor.
(2) The mechanical seal is worn or not installed in place; replace the upper and lower mechanical seals and dry the motor.
(3) O-rings are aging and lose their function; replace all sealing rings and dry the motor.
(5) In the submersible pump pipeline, pipeline or flange connection, there are often obvious reasons for water leakage and treatment methods:
① The pipeline itself is defective and has not been pressure tested;
②The gasket joint at the flange connection is not handled properly;
③ The flange bolts are not tightened in a reasonable way; the defective pipes should be repaired or even replaced, the center of the opposite pipe should be removed and rearranged, and the connecting bolts should be inserted and tightened in a basically free state after alignment. After all the pipelines are installed, the compressive strength and leakage test of the system should be carried out. It must be replaced with a new one.
Internal leakage of submersible pump:
When the submersible pump leaks, it will cause insulation damage, water immersion in the bearing, and alarm system alarm, forcing the unit to stop running.
The main reason is that the dynamic seal (mechanical seal) or static seal (special seal for cable inlet, O-ring) of the submersible pump is damaged, causing water seepage, and the power cable or signal cable is damaged causing water seepage. Various alarm signals such as water immersion, leakage, humidity, etc. alarm and stop; before installation, the quality of each sealing part should be checked; during installation, it is necessary to ensure that the end faces of each sealing part are in good contact; before running, check the phase-to-phase and ground insulation resistance of the motor and the Whether the sensor components of the system are in good condition. When the above fault occurs during operation, replace all damaged seals and cables and dry the motor. Disassembled seals and cables must not be reused.
Reverse when the submersible pump is stopped:
1. After the pump motor is powered off, the pump will reverse, the main reason is that the check valve or flap door in the water outlet pipeline fails.
2. Elimination measures Check before installation. The installation direction of the check valve should be correct, whether the center of the door is aligned, and the opening and closing should be flexible. Check the check valve or flapper frequently during operation, repair the damaged part or replace the check valve or flapper with guaranteed quality.
