Introduction of car water pump

Introduction:

Centrifugal water pumps are widely used in automobile engines. Its basic structure consists of water pump housing, connecting disc or pulley, water pump shaft and bearing or shaft-connected bearing, water pump impeller and water seal device and other parts.

working principle:

The engine drives the water pump bearing and the impeller to rotate through the pulley, and the coolant in the water pump is driven by the impeller to rotate together. At the center of the impeller, the coolant is thrown out and the pressure is reduced. The coolant in the water tank is sucked into the impeller through the water pipe under the action of the pressure difference between the inlet of the pump and the center of the impeller to realize the reciprocating circulation of the coolant.​​

The bearings that support the water pump shaft are lubricated with grease, so it is necessary to prevent the lubricant from leaking into the grease and emulsification of the grease, and also to prevent the leakage of the grease. The sealing measures for the water pump to prevent leakage include water seals and gaskets. The water seal dynamic seal ring and the shaft are installed between the impeller and the bearing through interference fit, and the water seal static seal seat is tightly press-fitted on the casing of the water pump, so as to achieve the purpose of sealing the coolant.​​

The water pump housing is connected to the engine through gaskets 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 from the drain hole, which has prevented the coolant from entering the bearing cavity, damaging the bearing lubrication and rusting the components. If the coolant still leaks after the engine is stopped, the water seal is damaged.

Drive of the water pump:

It is generally driven by the crankshaft of the engine through the V-belt. The transmission belt is surrounded between the crankshaft pulley and the water pump pulley. As soon as the crankshaft rotates, the water pump shaft rotates, and the water pump shaft drives the impeller to rotate, thereby converting mechanical energy into hydraulic energy.

The impeller is the core of the pump's work. The movement of the impeller itself is very simple, and it just rotates with the shaft. However, due to the action of the blades, the movement of the liquid in the impeller is very complicated; on the one hand, it is involved in the movement with the rotation of the impeller, and on the other hand, it is continuously thrown out of the rotating impeller under the driving of the blade, that is, the movement relative to the impeller. Therefore, the outer diameter of the impeller, the height and angle of the impeller blades, and the gap with the pump casing directly affect the performance of the pump.