The manufacturer introduces the working principle of scroll pump

Many radial blades are milled on the impeller of scroll pump. The end face of the impeller is close to the pump body, and its axial clearance is 0.10 ~ 0.15mm. It is composed of impeller cavity and pump cover. The section in the flow channel where the suction port is separated from the discharge port is called the spacer tongue. The radial clearance between the spacer tongue and the impeller is very small to prevent the high-pressure liquid at the outlet from leaking to the suction port. The blade of the open scroll pump is long, and the inner diameter of the blade is less than the inner diameter of the flow channel. The liquid enters the impeller from the suction port and then into the flow channel. The blade of the closed scroll pump impeller is short, and the inner diameter of the blade is equal to the inner diameter of the flow channel. The liquid enters the flow channel from the suction port, and then enters the impeller from the outer circumference of the impeller.

Now take the closed pump as an example to illustrate its working principle. The fluid enters the flow channel and impeller from the suction port. When the impeller rotates, because the centrifugal force of the moving liquid in the impeller is greater than that of the moving liquid in the channel, a vortex motion is generated between them, and its rotation center line is along the longitudinal direction of the channel, which is called longitudinal vortex. Under the action of longitudinal vortex, the liquid can enter and exit the impeller many times in the whole process from suction to discharge, which is similar to the flow condition of liquid in multistage centrifugal pump. Every time the liquid flows through the impeller, it obtains energy. When the liquid flows from the impeller to the runner, it is mixed with the liquid moving in the runner. Due to the different velocities of the two streams, momentum exchange occurs in the mixing process, which increases the energy of the liquid in the channel. Vortex pump mainly relies on this longitudinal vortex to transfer energy.