Why can the submersible pump be placed in the water and what is the protection mechanism

The submersible electric pump unit is composed of four parts: water pump, submersible motor bai (including cable), water pipe and control switch. The submersible pump is a single-suction multi-stage vertical centrifugal pumpChina DC Water Pumps Suppliers; the submersible motor is a closed water-filled wet, vertical three-phase squirrel cage asynchronous motor, and the motor and the water pump are directly connected through a claw-type or single-key barrel coupling; equipped with different specifications Three-core cable; the starting equipment is air switches of different capacity grades and self-coupling pressure reducing pneumatic actuators, and the water pipe is made of steel pipes of different diameters, connected by flanges, and the high-lift electric pump is controlled by gate valves.

The upper part of the submersible motor shaft is equipped with a labyrinth type sand control device and two reversing assembled skeleton oil seals to prevent quicksand from entering the motor. The submersible motor uses water-lubricated bearings, and the lower part is equipped with a rubber pressure regulating film and a pressure regulating spring to form a pressure regulating chamber to adjust the pressure change due to temperature; the motor winding is insulated with polyethylene, nylon sheathed water-resistant electromagnetic wire, and the cable connection method is as follows In the cable joint process, the insulation of the joint is removed and the paint layer is scraped off, connected separately, welded firmly, and wrapped with raw rubber. Then wrap 2-3 layers of waterproof adhesive tape, and 2-3 layers of waterproof tape on the outer bread or a layer of rubber (inside bicycle tire) to prevent water seepage.
A rubber bearing is installed in the diversion shell of each stage of the submersible pump; the impeller is fixed on the pump shaft with a conical sleeve; the diversion shell is integrated by threads or bolts. The upper part of the high-lift submersible pump is equipped with a check valve to avoid damage to the unit caused by water hammer during shutdown. The electrical secrets are closed, using precision stop bolts, and the cable outlet is sealed with rubber gaskets. There is a water injection hole at the upper end of the motor, a vent hole, and a drain hole at the bottom. The lower part of the motor is equipped with upper and lower thrust bearings, the thrust bearing has grooves for cooling, and its counter-grinding stainless steel thrust plate, which bears the up and down axial force of the water pump.