A multistage centrifugal pump is a pump that contains several stages within the piping system where pressure is applied to the liquid that is being pumped. Each stage in the system consists of an impeller and some accompanying diffusion components. In most cases, multistage centrifugal pumps are referred to with respect to the number of stages contained in the piping system. For instance, a multistage centrifugal pump with five stages is referred to as a five-stage pump. Some pumps may come with as much as 10 stages.
How it Works
The central idea behind a multistage centrifugal pump is fairly simple. In most industrial and liquid treatment plants, it’s necessary for liquids to be moved for vast distances using higher pressure. The only means of achieving higher pressures in most of such situations is with pumps that have several impellers. These multiple impellers are often mounted on a single shaft and the flow progresses from one level to the other, generating pressure as it moves.
In the first stage, the pump directs the fluid within the system into the pump’s suction port and from there the fluid is directed into the impeller’s inlet. The rotating impeller then pushes the fluid along the spinning vanes, increasing the velocity energy of the fluid. In the third stage, the fluid leaves the impeller vanes and it’s pushed into the pump’s diffuser or volute casing, where the high velocity energy of the liquid is converted into higher pressure through a process of diffusion. Finally, the liquid is directed into the pump’s discharge port and from there it is pushed out into the other stages where it goes through the same process and after the final stage and from there it goes into the piping system.
When the fluid in the impeller is pushed away from the impeller’s center, a low pressure zone is generated at the eye of the impeller and consequently more fluid flows into the pump. This ensures that a steady flow is always maintained through the impeller.
Applications
The multistage centrifugal pump can be employed in a wide range of applications that include cooling systems in industrial plants that generate immense heat during production, industrial circulation, chemical transfer and chemical spray, and in irrigating vast fields. It can also be used in most industrial and liquid treatment plants where it’s often necessary for liquids to be moved for vast distances using higher pressure and without interruption.
