The submersible pump is mainly composed of three parts: motor # water pump and lifting pipe! The motor and water pump are connected together! Completely Immerse Image # 3! 0 G/A vertical submersible sewage pump structure* Inlet end cover; O-ring seal $$* pump body $0 * impeller $5 * immersion detection port $% * mechanical seal $D * shaft $* Motor overload protection device! 4 * The connecting components work in water. "Figure # 3! 0 shows the structural schematic diagram of the G/A vertical submersible sewage pump." The suction port is located at the bottom of the pump! The discharge port is horizontally set. The vertical submersible motor is directly connected to the pump body! Overload protection device and immersion protection device ensure safe operation. The submersible pump is divided into water supply pump and sewage pump according to its purpose. The submersible sewage pump is divided into centrifugal # axial flow type and mixed flow type according to its impeller form. In recent years, the application of submersible pumps in industrial, mining and urban water supply and drainage engineering has become increasingly widespread. The main advantage of submersible pumps is that the motor and water pump are integrated! No long transmission shaft is needed! The weight is light. The motor and water pump are both submerged in the water! There is no need to build a ground pump room. As the motor is generally lubricated and cooled with water, maintenance costs are low. The pump runs underwater for a long time! Therefore, the sealing requirements for the motor are very strict! If the sealing quality is not good! Or poor usage management! Due to water leakage, the motor may burn out. "Submersible motors have special requirements compared to ordinary motors! There are usually several types of motors, such as dry # semi dry # wet # oil filled and air cushion sealed motors." (Chapter 2: Construction, Performance, and Application of Common Water Pumps. Dry motors are no different from ordinary motors, except for strengthening the insulation and moisture-proof of the winding. As dry submersible motors do not allow the conveyed liquid to enter the motor cavity, good sealing measures need to be taken at the shaft extension end of the motor. "Mechanical sealing devices are usually used." However, due to the complex structure of this sealing device, high processing requirements! If the water contains sediment, the sealing components are easily worn! This makes the seal ineffective! Therefore, clean water without sediment needs to be pumped! The use of mechanical seals has a better effect. Semi dry electric motors only seal the stator of the motor and let the rotor rotate in water. Wet electric motors fill the stator cavity of the motor with clean water or distilled water! The rotor rotates in clean water! The stator is wound with waterproof insulation wires such as polyethylene and nylon to solve the cooling problem of the motor winding and water lubricated bearings. The motor cavity is filled with clean water! The shaft seal of this pump only serves to prevent mud and sand from entering the motor! The structure is relatively simple! Easy to manufacture and maintain, but this type of pump has high requirements for the insulation wires and water lubricated bearing materials used in the motor stator! It also needs to consider the issue of rust prevention and corrosion of components. Oil filled motors are filled with insulation oil, such as transformer oil, inside the motor! Prevent water and moisture from entering the motor winding! The motor stator coil of this pump is wound with oil and water resistant enameled wire with reinforced insulation to prevent water and sediment from entering and oil leakage. The motor rotor of this pump rotates in oil with high viscosity, causing significant power loss and efficiency decrease. Generally, a mechanical seal is required at the extension end of the motor shaft to prevent water and sediment from entering and oil leakage. However, there is an air sealed chamber at the lower end of the motor! And it is connected to the outside world through several holes. After the pump submerges into the suction pool, the air in the sealed chamber forms an air cushion under the action of external liquid pressure! The appearance and installation diagram of the G/A pump in Figure # 3! 5 are designed to prevent liquid from entering the motor cavity. As this type of pump is only suitable for situations with small and stable diving depths, there is a risk of water entering the motor cavity due to the dissolution of air in this sealing method! Therefore, it is rarely used. Many models of submersible pumps are equipped with automatic coupling devices! There is a roller at the pump outlet end! Roll up and down inside the guide rail! The coupling device ensures that the pump's outlet is automatically coupled and disconnected from the fixed outlet bend on the foundation! The maintenance work of the pump can be carried out outside the pool. The lower end of the vertical guide rail is fixed on the bend support! The upper end is welded and fixed with the top beam or wall of the sewage pool. The outlet bend side and the embedded steel plate inside are welded and fixed. The bearing is shared with the submersible motor. The shaft seal adopts a mechanical seal! The transmission is coaxial with the submersible motor! It is directly driven by the motor. Figure # 3! The appearance and installation diagram of the G/A pump are shown in Figure 5. The commonly used model for submersible water pumps is GZQ! Its flow range is # 44 "044&$'! Head range is% "5"% 4&: #;! The power range is!! The commonly used models for submersible axial and mixed flow pumps are BGA and GA models! The outlet diameter is $54 "! 044&&", and the single machine flow rate can exceed # 4C! 40&$'P "model meaning) For example