Pump axial thrust is how to balance

Balance hole to drive so cannot too big, mainly affect the efficiency of pump, the following introduce several methods of water pump axial thrust balance. For single pump axial force balance generally have the following format: 1, the opening balance hole in pump HouGaiBan drill a few holes near the hub, and add a sealing ring on HouGaiBan, the outside diameter of the suction impeller sealing ring diameter is equal. Pump work, HouGaiBan fluid and suction are interlinked in the sealing ring, the pressure and suction pressure. Sealing ring outside HouGaiBan area with inhaled outlets are equal in the area of the front cover, and sent the liquid pressure in the former, the total force on the HouGaiBan basic equal, a few not be balanced by the axial force bearing. In general, open the balancing hole axial force effect is better. Its characteristic is: leakage is more, after balance hole liquid and interfere with the normal flow of the impeller inlet liquid, reduce the efficiency of the centrifugal pump 2 - Around 5%, only applies to small single stage centrifugal pump. 2, this method is used to balance the tube with open balance hole method is basically the same, in a setting with suction impeller HouGaiBan corresponding mouth ring, using balance tube at the entrance of the sealing fluid is introduced into the pump in the space, the balance of this part of the hydraulic pressure and the inlet pressure, so that the axial force balance, the device requires balance pipe through the flow area should be equal to or greater than 4 - ring gap flow area 5 times. 3, in the back of the impeller HouGaiBan symmetrical balance blades placed several radial reinforcement, when the impeller rotation, and tendons piece like pump vane blade on the back of the liquid to speed up the rotation, centrifugal force increase, a significant reduction in the blade on the back of the pressure, so that the impeller on both sides of the pressure balance, the balance depends on the balance the clearance between the pump body and the size of the blade and blade. The disadvantage is that pump efficiency is lower. 4, adopts the double suction impeller in the flow of the larger single-stage centrifugal pump or on a multistage centrifugal pump adopts double inlet of impeller and the axial thrust working conditions be balanced by itself, but in fact due to the manufacturer's hard on both sides of the flow components of pump geometry completely consistent, so there will be a smaller axial force on the rotor, therefore, on one side of the pump shaft single centripetal ball bearings. In addition, axial balance device for multi-stage pump, the impeller can be used symmetrical layout method, the balancing hub axial force and the balancing disc axial force and other forms.