In the previous sharing, we introduced the hazards of cavitation in detail, so what are the effective measures that we could take to prevent this culprit which severely reduces the work-life of the slurry pumps?
1. Flow parts made of anti-abrasive materials
The use of certain materials with good anti-cavitation damage performance can reduce the degree of cavitation damage and increase the working life of the slurry pump flow parts. Such as titanium alloy, nickel alloy and other alloy material flow parts, can obtain excellent anti-cavitation damage performance.
2. Improve the processing accuracy and smoothness of the surface of the flow part
The surface of the flow parts of the slurry pump, especially the surface manufacturing quality, geometric accuracy and surface of the parts prone to cavitation, will have a certain impact on the cavitation performance of the pump. Rough or dirty flow parts, when the flow rate is small, due to the thick boundary layer, will not have any impact on the cavitation performance, but in the case of large flow, it will affect the starting point of cavitation.
In addition, a relatively rough or non-smooth surface will cause stress concentration under cavitation conditions, thereby accelerating the destruction of the material.
Errors in the geometry and machining accuracy of the flow-through components will cause changes in the liquid flow, such as vortex, impact and local diffusion, thereby increasing the chance of cavitation, especially the head near the inlet of the impeller vanes. The size of the part, the position of the inlet side, the size of the gap between the impeller and the sealing ring or the pump casing, etc., will all have a certain impact on the anti-cavitation performance of the impeller.
3. Good design of the suction connection and suction pipeline
The pressure in the suction flange and the suction pipe of the slurry pump is usually very low. If their size and shape are not selected properly, cavitation will easily occur in them. Therefore, the correct design of the suction inlet and the suction pipeline to ensure that the liquid flow has the smallest resistance loss in it, and that the liquid flow has good flow performance before entering the impeller, which will greatly improve the cavitation performance of the pump.
First of all, the shortest suction pipeline should be used to make the structure the simplest and facilitate the flow of liquid, and minimize unnecessary pipeline accessories, such as elbows, accessories, etc.
In addition, the diameter of the suction pipe should be selected correctly. If the suction pipe diameter is too large, there will be backflow phenomenon in the small flow condition, and if the diameter is too small, it will produce a larger suction friction loss, which will reduce the liquid pressure at the suction port of the impeller, which is not conducive to cavitation. The influence of the suction pipe diameter on the cavitation performance of the pump has been verified by the conducted experiments. A too small suction pipe diameter will cause the pump cavitation conditions to be generated , thereby greatly reducing the adjustable performance of the pump.
The influence of the size and structure of the suction inlet on the cavitation performance of the pump is very obvious, so more attention should be paid.
4. Reduce the vibration of the slurry pump unit during operation
Slurry pump is a kind of rotating machinery, it will produce some vibration more or less when it is running. Sometimes, external mechanical vibration will also affect the operation of the pump, causing additional vibration when the pump is running. The cavitation of the material liquid in the slurry pump will cause the vibration of the unit. On the contrary, the vibration of the unit will also affect the cavitation performance of the pump, and also produce other adverse effects. Therefore, vibration should be minimized or eliminated during the operation of the unit to improve the hydraulic performance and cavitation performance of the slurry pump.
Anyway if your pump system already been installed and faced with such cases, Qiangda experts are willing to help always, we will offer engineering help and also OEM parts to solve your problem.