Working principle of centrifugal sand pump

Centrifugal sand pump is mainly composed of impeller and volute. After starting, the impeller rotates to generate centrifugal force, and the liquid is sucked from the middle of the impeller. Under the high-speed rotation of the impeller, after the liquid passes through the flow channel in the impeller, it continuously gains energy under the action of centrifugal force, and then the energy is converted into pressure energy, which enters from the outlet. People into the discharge pipe.

After the liquid in the impeller is thrown out, a vacuum is formed in the center of the impeller. One end of the suction pipe of the pump communicates with the center of the impeller, and the other end is immersed in the liquid being transported. Under the action of the pressure difference between the liquid surface pressure (usually atmospheric pressure) and the pressure in the pump (negative pressure), the liquid is sucked The human pipeline enters the human pump to fill the position where the liquid is discharged. As long as the impeller keeps rotating, the centrifugal pump will continuously suck people and discharge liquid.

When the centrifugal sand pump is started, if the pump and the suction pipe are not filled with liquid, it has no ability to pump liquid. This is because the density of air is much smaller than that of liquid, and the centrifugal force generated by the rotation of the impeller is not enough to produce the vacuum required to suck up the liquid.

The phenomenon that there is gas in the pump casing and the liquid cannot be sucked is called gas binding. In order to prevent the occurrence of air-binding phenomenon, the centrifugal pump should be filled with liquid before starting. This operation is called pumping. In order to prevent the liquid in the pump casing from flowing into the low tank due to gravity, a check valve is installed at the entrance of the pump suction pipe. If the pump position is lower than the liquid level in the tank, there is no need to prime the pump when starting.