Service life and precautions of high-lift sewage pump
Sewage pumps are a kind of centrifugal impurities and have many forms: submersible and dry. At present, the most commonly used submersible is WQ high-lift sewage pump, and the most common dry sewage pump is W horizontal sewage pump. There are two types of pumps and WL vertical sewage pumps. It is mainly used to transport urban sewage, feces or liquids containing fibers, paper scraps and other solid particles. The temperature of the transported medium is usually not more than 80°C. Because the conveyed medium contains fibers that are easy to entangle or bunch. Therefore, the flow passage of this kind of pump is easy to be blocked. Once the pump is blocked, the pump will not work normally, and even the motor will be burned, resulting in poor sewage discharge. It has a serious impact on urban life and environmental protection.
High-lift sewage pump
How to extend the service life of high-lift sewage pump:
1. Prohibition of abnormal power supply voltage
Because the low-voltage power supply line is relatively long, the end voltage of the line is often too low. When the phase voltage is lower than 198 volts and the line voltage is lower than 342 volts, the speed of the sewage pump motor will decrease. When it does not reach 70% of the rated speed, the centrifugal switch will be turned on, causing the starting winding to be energized for a long time and cause heat or even burn Windings and capacitors. On the contrary, excessive voltage causes the motor to overheat and burn out the windings. Therefore, during the operation of the sewage pump, the operator must observe the power supply voltage value at any time. If it is less than 10% of the rated voltage and more than 10% of the rated voltage, the motor should be stopped to find the cause and troubleshoot.
2, confirm the correct rotation direction of the motor
It is necessary to find out the direction of rotation of the motor. Now there are many types of sewage pumps that can output water during forward and reverse rotation, but the water output is small and the current is large during reverse rotation. The long reverse rotation time will damage the motor windings.
3. Installation of leakage protector
Leakage protector is also called life-saving device, its function can be understood from the three words "life-saving device". Because the sewage pump works underwater, it is easy to leak electricity and cause power loss and even cause electric shock accidents. If a leakage protector is installed, as long as the leakage value of the sewage pump exceeds the operating current value of the leakage protector (generally no more than 30 mA), the leakage protector will cut off the power supply of the sewage pump to ensure safety and avoid leakage and waste of electricity.
4. Cable installation and insulation resistance requirements of submersible pumps
When installing the sewage pump, the cable should be overhead and the power cord should not be too long. Do not stress the cable when the sewage pump is launched or lifted, so as not to cause the power cord to break. Do not sink into the mud when the sewage pump is working, otherwise it will cause poor heat dissipation of the motor and burn the motor windings. During installation, the insulation resistance of the motor should not be less than 0.5 megohm.
5. Avoid frequent switching
Do not switch the sewage pump frequently. This is because when the electric pump stops rotating, it will produce backflow. If it is turned on immediately, the motor load will start, causing the starting current to be too large and the winding will be burned. Due to the large current when starting, frequent starting will also burn out the windings of the sewage pump motor.
6. Don't let the sewage pump be overloaded for a long time
In order to avoid long-term overloading of the sewage pump, do not pump water with a large amount of sand and observe whether the current value is at the value specified on the nameplate at any time. If the current is found to be too large, it should be shut down for inspection. In addition, the dehydration operation time of the water pump should not be too long, so as to avoid overheating and burning of the motor.
7, pay attention to daily maintenance
Always check the motor frequently. If cracks in the lower cover, damage or failure of the rubber sealing ring, etc. are found, they should be replaced or repaired in time to avoid water infiltration into the sewage pump.
Notice for use of high-lift sewage pump:
(1) Check the sewage pump pipeline and joints for looseness. Turn the sewage pump by hand to see if the sewage pump is flexible.
(2) Add bearing lubricating oil to the bearing body, observe that the oil level should be at the center line of the oil standard, and the lubricant should be replaced or replenished in time.
(3) Unscrew the water diversion screw plug of the sewage pump body, and fill the water diversion (or slurry).
(4) Close the gate valve of the outlet pipe, the outlet pressure gauge and the inlet vacuum gauge.
(5) Jog the motor, and try to see if the rotation of the motor is correct.
(6) Turn on the motor. When the sewage pump is running normally, open the outlet pressure gauge and the inlet vacuum pump to see the proper pressure, then gradually open the gate valve and check the motor load.
(7) Try to control the flow and head of the sewage pump within the range indicated on the label to ensure that the sewage pump runs at the highest efficiency point in order to obtain the greatest energy saving effect.
(8) During the operation of the sewage pump, the bearing temperature should not exceed 35℃, and the maximum temperature should not exceed 80℃.
(9) If abnormal sound is found in the sewage pump, stop immediately and check the cause.
(10) To stop using the sewage pump, first close the gate valve and pressure gauge, and then stop the motor.
(11) The sewage pump shall change the lubricating oil after 100 hours in the first month of operation, and then change the oil once every 500 hours thereafter.
(12) Adjust the packing gland frequently to ensure that the dripping in the packing chamber is normal (it is better to leak out as drips).
(13) Regularly check the wear of the shaft sleeve, and replace it in time when the wear is large.
(14) When the sewage pump is used in the cold winter season, after stopping, unscrew the drain plug at the bottom of the pump body to drain the medium. Prevent freezing and cracking.
(15) If the sewage pump is out of service for a long time, it is necessary to disassemble all the pumps, wipe off the water, and coat the rotating parts and joints with grease and install them.
