Cam pumps and screw pumps belong to the same category of positive displacement pumps and have similar performance. Both can smoothly transport high viscosity substances and have higher conveying pressures. So, what are the differences between cam pumps and screw pumps?
Cam pumpThe difference between cam pump and screw pump.Screw pump
1. The internal structure is different. A cam pump uses two cams to rotate in opposite directions inside the pump chamber, increasing the volume from the inlet to the outlet to achieve the purpose of conveying materials. A screw pump uses a spiral screw to rotate inside a rubber stator, allowing materials to be sent out from the outlet from the front to the back of the screw rotation.
2. The difference in the lifespan of accessories. Due to the lack of friction between the components of the cam pump, the wear parts of the cam pump have a long service life; The wear on overcurrent components mainly comes from abrasive and corrosive components in the medium; On the contrary, the friction between the cam and stator of the screw pump, as well as particles in the medium, simultaneously affect the service life of the worn parts. The eccentric rotation of the cam generates stress on the stator, exacerbating the wear between the legs. Even if the conveyed medium does not contain any particles, the stator of the pump will gradually wear out.
3. Different levels of hygiene. Due to the non streamlined cavity of the screw pump, there are numerous defects inside the cavity, making it impossible to become a sanitary pump. Damage to the cavity wall made of PTFE or rubber is more likely to cause contamination of the conveying medium. In contrast, due to the streamlined structure of the cam, there are essentially no dead corners or non-metallic parts in the cam chamber of the cam pump. Therefore, high viscosity volumetric pumps are more suitable for industries such as food and beverage, pharmaceuticals, etc. that require high hygiene requirements, especially with the increasing automation of production lines and the use of online cleaning. This shows the importance of choosing a cam pump. Therefore, the hygiene level of cam pumps is higher than that of screw pumps.
4. The conveying direction is different. The conveying direction of the cam pump can be reversed; The pump has a completely symmetrical structure; However, screw pumps cannot be reversed, and the seal is under pressure during reverse conveying.
5. The self-priming ability is different. Screw pumps have excellent self-priming ability, but it is important to avoid pump idling and not exceed 30 seconds; Cam pumps can produce excellent self-priming ability at speeds greater than 200rpm.
