When the pump rotor is working at high speed, if the mass is not balanced, a large centrifugal force will be generated when rotating, causing the pump to vibrate or be damaged. The balance of the rotor is achieved by the mass balance of the various components (including the shaft, the impeller, the bushing, the balance plate, etc.), so the static adjustment of the newly installed impeller should be performed. The specific method is:
(1) Mount the impeller on the dummy shaft and place it on the static balance test bench that has been adjusted to the level. There are two tracks on the test bench, and the dummy shaft can roll freely on it.
(2) Mark the side of the impeller. If the impeller mass is not balanced, the heavier side will always automatically turn to the underside. Add weights at the symmetrical position (ie, the lighter side) where the weight is heavy (use the surface to stick or use a clip to increase or decrease the iron piece) until the impeller can stop at any position.
(3) Weigh the mass of the weighting block. Instead of adding weight to the lighter side of the impeller, the weight of the impeller is balanced by weight reduction on the heavier side. When reducing weight, you can use milling machine milling or grinding with a grinding wheel (when the removal is not large), but note that the depth of milling or grinding should not exceed 1/3 of the thickness of the impeller cover. After the static balance of the impeller, the static balance allowable deviation value shall not exceed the product of the outer diameter of the impeller and 0.025 g/mm. For example, an impeller with a diameter of 200 mm allows a deviation of 5 g.
