1. What is a submersible pump for?
A submersible pump is a device dedicated to extracting water from deep underground. In the process of use, the entire equipment is immersed in the bottom of the water for work, and then the underground water source is extracted to the surface. Submersible pumps are widely used in hot spring bathing, and can also be used to extract groundwater from deep wells, and can also be used in water extraction projects such as rivers, reservoirs, and canals. It is mainly used for farmland irrigation and water for people and animals in high mountain areas. It can also be used for central air-conditioning cooling, heat pump units, cold pump units, cities, factories, railways, mines, and construction site drainage.
According to different needs, there are many categories of submersible pumps, such as deep well submersible pumps, submersible sewage pumps, submersible axial flow pumps, large submersible electric pumps, hot water submersible pumps, stainless steel submersible pumps, submersible screw centrifugal pumps, etc. Wait. There are some submersible pumps that can only pump clear water, and must not contain debris, or the debris particles are small, such as deep well submersible pumps, hot water submersible pumps, etc. There are some submersible pumps that can pump muddy water, rainwater, etc., such as submersible sewage pumps, but the requirements for particle size are stricter, and too large cannot be pumped. Because of its unique structural characteristics, the submersible screw centrifugal pump can pump larger materials, such as live fish, potatoes, apples, etc.
Second, the structure of the submersible pump
The submersible pump unit consists of: water pump, submersible motor (including cables), water pipes and control switches. The submersible pump is a single-suction multi-stage vertical centrifugal pump; 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 by a claw or single-key barrel coupling; equipped with different specifications. Three-core cable; the starting equipment is air switch of different capacity grades and auto-decompression pneumatic actuator, the water pipe is made of steel pipe with different diameters, connected by flange, and the high-lift electric pump is controlled by gate valve.
The upper part of the submersible motor shaft is equipped with a labyrinth type sand control device and two skeleton oil seals assembled in the reverse direction to prevent quicksand from entering the motor. The submersible motor adopts 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 caused by temperature; the motor winding is insulated by polyethylene, and the nylon sheath is water resistant. 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 a layer of raw rubber. Then wrap 2-3 layers of waterproof adhesive tape, and wrap 2-3 layers of waterproof tape on the outside or wrap a layer of rubber (bicycle lining) with water glue to prevent water seepage.
A rubber bearing is installed in the guide casing of each stage of the submersible pump; the impeller is fixed on the pump shaft with a conical sleeve; the guide casing is connected by threads or bolts. The upper part of the high-lift submersible pump is equipped with a check valve to avoid the damage of the unit caused by water hammer during shutdown. The motor is airtight, using precision stop bolts, and the cable outlet is sealed with a rubber gasket. There is a water injection hole at the upper end of the motor, a vent hole, and a water drain hole at the bottom. The lower part of the motor is equipped with upper and lower thrust bearings, and there are grooves on the thrust bearings for cooling.
Three, the working principle of the submersible pump
There are several types of submersible pumps, and the wire package in the motor includes oil-immersed and water-immersed. is dry. Before using it, you must read the instructions first, and make no mistake. If you don’t use it for a long time, you must turn the impeller before using it, otherwise it will burn the bag because it will not be stuck for a long time.
The suction line and pump must be filled with liquid before starting the pump. After the pump is turned on, the impeller rotates at a high speed, and the liquid in it rotates with the blades. Under the action of centrifugation, it flies away from the impeller and is ejected outward. Outlet, the discharge pipe flows out. At this time, a vacuum low-pressure area with neither air nor liquid is formed at the center of the blade due to the liquid being thrown around. The liquid in the liquid pool flows into the pump through the suction pipe under the action of the atmospheric pressure on the pool surface, and the liquid is thus continuous. It is continuously sucked up from the liquid pool and continuously flows out of the discharge pipe.
