What is the wear reason and repair method of rotor and blade in vane pump of injection molding machine?
(1) causes of rotor wear and repair
The wear of the rotor is mainly caused by friction between the end face of both sides and the oil distribution disc, which is generally mild.This friction is caused by the poor precision and quality of the bearing supporting the rotor shaft, or the improper installation, sometimes resulting in axial movement.
Minor wear of the rotor to repair this minor wear refers to the two sides of the rotor end surface with scratches.When the scratch is relatively shallow, it can be used to grind with polishing paste or oilstone to remove the scratch and burr before assembling.
In case of serious wear and tear on both ends of the rotor and there are serious grooves, the end surface of the rotor used in the grinder should be ground against the end surface of the rotor until the groove marks are removed.After grinding, the end surface roughness of the rotor shall be no more than 0.63 centimetres, the vertical tolerance between the end surface and the center line of the rotor shall be 0.01mm, and the non-parallelism tolerance between the two ends shall be 0.008mm.It should be noted that the rotor end surface has been ground and repaired, so the blade width in the rotor slot should also be ground, and the blade width should be slightly less than the rotor slot length.
The wear of blade groove on rotor is mainly the result of blade sliding frequently in the groove.When a minor scratch occurs, fine oil can be used to repair the grinding.For severe wear, the blade can be ground on the tool grinding machine with a thin grinding wheel and then rearranged according to the groove width after grinding.The matching clearance between blade and groove width should be within the range of 0.013 ~ 0.018mm.
(2) wear and repair of blade
The wear of the blade is mainly the result of the blade sliding in and out of the rotor groove frequently when the rotor rotates at high speed.It is found that blade sliding is not flexible or stuck, which may be caused by burrs or slippage on blade sliding surface. Generally, the blade surface can be ground to remove burrs or scratches.