At the suction port of a single-suction centrifugal impeller, the front side of the rear panel is subjected to suction pressure and the rear side is subjected to high pressure. In addition, due to the unequal leakage of seals on both sides, the pressure distribution on the impeller covers is also different. Therefore, the force acting on the impeller by the liquid is unbalanced (as shown in the following figure), resulting in an axial force F1 acting on the impeller parallel to the axis, pointing from the rear cover to the impeller inlet.
Liquid flows into the impeller inlet and outlet from the impeller speed and size of the same direction. Therefore, a reaction force F2 acts on the impeller, which is also axial, but opposite to F1.
For vertical pumps, the weight of the entire rotor is also part of the axial force. Impeller symmetrical arrangement, such as open multi-stage pump, two-stage pump, cantilevered two-stage pump, able to balance the axial force. But in some cases it looks like the shape is symmetrical and the axial force of the impeller seems to be balanced. In fact, due to the different diameters of the pillow block, sleeve and hub, there are still remaining axial forces, which Part of the axial force is sometimes very large, and can even damage the bearings. In addition, due to the difference in pressure between the working face and the back of the twisted blade, an axial force will also be generated in the same direction as F1, but there is currently no suitable method to calculate the magnitude of this axial force, Power is not, generally can not be considered.
Auto Transmission Parts,Aluminum Transmission Componerts,Worm Gearbox Parts,Automotive Transmission Part
Ningbo Beilun Huasheng Mould Factory , https://www.huashengmoulds.com