Water ring vacuum pump

Working principle

The impeller of the water ring vacuum pump blade is eccentrically installed inside the cylindrical pump casing. Inject a certain amount of water into the pump. When the impeller rotates, water is thrown into the pump casing to form a water ring, and the inner surface of the ring is tangent to the impeller hub.

Due to the lack of concentricity between the pump casing and impeller, the intake space between the right half hub and the water ring gradually expands, forming a vacuum that allows gas to enter the intake space inside the pump through the intake pipe.

Subsequently, the gas enters the left half, and due to the gradual compression of the volume between the hub rings, the pressure increases. As a result, the gas is discharged outside the pump through the exhaust space and exhaust pipe.

Advantages of water ring vacuum pump

● The structure is simple, the manufacturing accuracy requirement is not high, and it is easy to process.

● The structure is compact, the pump has a high rotational speed, and can generally be directly connected to an electric motor without the need for a deceleration device. Therefore, using a small structural size can achieve a large exhaust volume and a small footprint.

● Compressed gas is essentially isothermal, meaning that the temperature change during the compression process is minimal.

● Due to the absence of metal friction surfaces in the pump chamber, there is no need for lubrication inside the pump, and the wear is minimal. The sealing between the rotating and fixed parts can be directly achieved by a water seal.

● Uniform suction, stable and reliable operation, simple operation, and easy maintenance.

Disadvantages of water ring vacuum pump

◆ The efficiency is low, usually around 30%, with better ones reaching up to 50%.

◆ The low vacuum degree is not only due to structural limitations, but more importantly, it is limited by the saturated vapor pressure of the working fluid. Using water as the working fluid, the maximum pressure can only reach 2000~4000Pa. Using oil as the working fluid can reach up to 130Pa.

Application of water ring vacuum pump

The water ring pump was initially used as a self-priming pump, and gradually applied to many industrial sectors such as petroleum, chemical, machinery, mining, light industry, medicine, and food. In many industrial production processes, such as vacuum filtration, vacuum water intake, vacuum feeding, vacuum evaporation, vacuum concentration, vacuum moisture regain, and vacuum degassing, the water ring pump has been widely used.

Due to the rapid development of vacuum application technology, water ring pumps have always been highly valued for obtaining rough vacuum.

Due to the isothermal compression of gas in water ring pumps, flammable and explosive gases can be extracted.

Due to the absence of exhaust valves and friction surfaces, dust laden gases, condensable gases, and gas water mixtures can be extracted.

Therefore, the application of water ring pumps is increasing day by day.