I. Components, impeller and blades of centrifugal pump.
1. Increasing the inlet diameter of impeller can reduce the inlet velocity of the impeller and improve the cavitation performance of the pump, but the hydraulic efficiency of the pump is reduced.
2. Increase the width of the inlet edge of the blade so as to reduce the relative speed of the impeller inlet, thus improving the cavitation performance of the pump.
3. The smoother the finish of the impeller inlet, the smaller the hydraulic loss will be, and the anti-cavitation performance of the pump will be significantly improved. Stainless steel chemical pump
(4), impeller balance holes, its discharge to enter the mainstream of impeller damage, balance hole area should be no less than 5 times of seal clearance, to reduce the discharge rate, thereby reducing the impact on the mainstream, to improve pump cavitation resistance
5. The inlet edge of the blade is extended appropriately to the suction inlet, so that the liquid can accept the blade early and increase the surface area of the blade, reducing the pressure difference between the working face and the back of the blade. In addition, the front extension of the blade reduces the radius of the inlet side, thus reducing the pressure drop. But. The blade must be very thin at the front of the blade, otherwise it will be crowded out.
6. The thinner the inlet thickness of the blade is, the closer it is to the streamlined shape, and the maximum thickness of the blade is further away from the inlet. The lower the pressure drop of the blade inlet is, the better the cavitation performance of the pump is. The shape of blade inlet is very sensitive to pressure drop.
II: the impeller of centrifugal pump impeller can improve the anti-cavitation performance of the pump, and the effect is very significant.
1. Reduce the height of geometry listening and suction (or increase the height of geometric inversion);
2. Reduce the loss of inhalation, so as to increase the diameter of the pipe and minimize the length of pipe, elbow and accessories;
3. The pump increases NPSHr while the large flow is running, and NPSHa decreases. Therefore, when determining the installation height, NPSHa should be much larger than NPSHr, otherwise it should be prevented from running under large traffic for a long time.
4. Double suction pump at the same speed and flow rate. According to the formula of cavitation ratio, if the cavitation ratio of the two pumps with the same rotation speed and the same flow rate, the NPSHr of the pump with double suction impeller is 0.63 times that of the single suction impeller pump.
5. When the pump is cavitating, the application flow is small or slow.
III: can choose cavitation resistance strong material, for mechanical products, parts and components on the surface of the light, the higher the material strength and toughness, higher hardness and chemical stability, the material of the better resistance to cavitation performance.
- Close This Page
- Recommendation：
- Browse：
