Precautions for submersible pump maintenance

1. Replace the lubricating oil: open the oil hole screws inside the sealing chamber and the motor respectively, release all the lubricating oil in the sealing chamber and the motor, and replace the new oil to ensure the normal operation of the lubrication system.
2. Check the wearing parts: the impeller, buckle ring, shaft sleeve, bearing seat and so on of the submersible pump are wearing parts. First of all, the pump should be partially removed and the wearing parts should be checked to see if they are in good condition. It is strictly forbidden to use damaged and non-conforming spare parts.
3. Dismantle the pump casing to prevent rusting: Before using in spring, the top pump casing should be disassembled, and then the brake should be closed and started after rotating the impeller to prevent the parts from rusting and not starting normally and burning the motor. This maintenance is especially important for water-filled motors.
4. Drying motor: Use a 500 megaohm meter to measure the insulation resistance of the winding of the submersible pump and the shell, if the resistance value is less than 0.5 megaohms, the motor moisture should be expelled. The drying methods are: external drying method, current drying method and combined drying method of both at the same time. The external drying method is to use an external heat source for treatment, and the commonly used measures are: (1) blowing hot air: using the blower of the electric heater (a small agricultural submersible pump can use an electric hair dryer) to blow hot air to achieve the purpose of drying treatment; (2) Bulb baking: In a closed box, use several bulbs of about 200 watts for baking. Note that the baking temperature should not be too high, and should be controlled below 125°C; (3) Current drying: The three-phase windings of the motor can be connected in series or parallel according to the impedance of the submersible pump and the size of the power supply, and then connected to a variable resistor, and the current amount can be adjusted to about 60% of the rated current value, and the electricity can be dried.
5. Ensure sealing: agricultural submersible pumps have very strict requirements for sealing, when replacing the lubricating oil in the sealing chamber, if the oil is found to be turbid and the water content is high, the sealing box or sealing ring must be replaced or replaced as a whole to ensure that its sealing performance is good.
6. Check the bearing: check the upper and lower bearings of the motor part, if it is found that the wear or clearance is too large, the new bearing must be replaced in time, and it is strictly forbidden to use it "with illness". The inspection method is as follows: if the motor is running, there is a "click" sound, and the cycle is proportional to the speed, and it feels laborious when turning the rotor by hand, it is a little astringent or avulsion on the bearing raceway; If there is an intermittent "choking" sound in the bearing, there is an uncertain dead center when turning the rotor by hand, which is generally the ball frame is damaged, the inner ring is broken or the ball is broken. In the above situation, the bearing must be replaced to avoid further damage.
7. Ensure bearing lubrication: check and replace the skeleton oil seal and lithium-based grease of the bearing chamber of the upper and lower end covers for the water-filled submersible pump. In order to ensure that the bearing works in a well-lubricated condition for a long time.