Mechanical Water Pump 11518482251 for BMW

Centrifugal water pumps are widely used in automobile engines. Its basic structure is composed of water pump housing, connecting disc or pulley, water pump shaft and bearing or shaft bearing, water pump impeller and water sealing device and other parts. The engine drives the pump bearing and impeller to rotate through the pulley, and the coolant in the pump is driven by the impeller to rotate together, and is thrown to the edge of the pump housing under the action of centrifugal force, and at the same time generates a certain pressure, and then flows out of the outlet or water pipe. The pressure in the center of the impeller decreases due to the coolant being thrown out, and the coolant in the water tank is sucked into the impeller through the water pipe under the pressure difference between the water pump inlet and the center of the impeller, so as to realize the reciprocating circulation of coolant. 　　The bearings that support the shaft of the water pump are lubricated with grease, so it is necessary to prevent the leakage of coolant into the grease and the emulsification of the grease, as well as the leakage of coolant. The sealing measures to prevent leakage of water pumps include water seals and gaskets. The water-sealed dynamic seal ring and the shaft are installed between the impeller and the bearing through interference fitting, and the water-sealed static seal seat is tightly attached to the housing of the water pump, so as to achieve the purpose of sealing the coolant. 　　The water pump housing is connected to the engine by a gasket and supports moving parts such as bearings. There is also a drain hole on the water pump housing, which is located between the water seal and the bearing. Once the coolant leaks through the water seal, it can be leaked out of the drain hole, which has prevented the coolant from entering the bearing cavity, destroying the bearing lubrication and the corrosion of the components. If coolant is still leaking after the engine has been stopped, the water seal has been damaged. Generally, the crankshaft of the engine is driven by a V-belt. The transmission belt is surrounded between the crankshaft pulley and the water pump pulley, and the water pump shaft will follow the operation of the crankshaft as soon as it rotates, and the water pump shaft will drive the impeller to rotate, so as to realize the conversion of mechanical energy into hydraulic energy. 　　The impeller is the core of the pump's work, and the movement of the impeller itself is simple, just rotating with the shaft. But due to the action of the blades, the movement of the liquid in the impeller is complex; On the one hand, it is implicated with the rotation of the impeller, and on the other hand, it is continuously thrown out of the rotating impeller under the drive of the blades, that is, the movement of the relative impeller. Therefore, the outer diameter of the impeller, the height and angle of the impeller blades, and the clearance between the impeller blades and the pump housing directly affect the performance of the pump.