Custom Liquid Ring Vacuum Pump

Liquid Ring Vacuum Pump Introduction

Liquid Ring Vacuum Pump is an eccentric rotor with fixed blades, which throws water or other liquid to the stator wall and forms concentric liquid ring with the stator. Rotor blade and liquid ring together constitute a variable volume rotary variable volume vacuum pump.

Liquid Ring Vacuum Pump is a kind of coarse vacuum pump. The limit vacuum it can reach is about 2000-4000Pa [5]. When it is combined with Roots vacuum pump, the limit vacuum can reach 1-600 Pa. Water-ring vacuum pump can also be used as compressor, called water-ring compressor, is a kind of low-pressure compressor, its pressure range is 1-2*105Pa (gauge pressure).

The process of gas compression by Liquid Ring Vacuum Pump is approximately isothermal. For this reason, Liquid Ring Vacuum Pump can be used to suck or compress flammable and explosive gases, and can adapt to the severe working conditions such as large drainage and load shock fluctuation; in papermaking, petrochemical, fertilizer, coal, metallurgy, building materials, electrical appliances, pharmaceuticals, medical, environmental protection, printing, textile, plastics, packaging, shipping and other industries. It has been widely used. It also plays an important role in the process of vacuum disinfection, vacuum distillation, vacuum concentration, vacuum evaporation, vacuum degassing and vacuum moisture regain. Due to the rapid development of vacuum application technology, people pay more and more attention to the rough vacuum of Liquid Ring Vacuum Pump. EVP Liquid Ring Vacuum Pump Custom Made according to user’s requirements.

Liquid Ring Vacuum Pump Working Principle

When the Liquid Ring Vacuum Pump works, the motor drives the impeller to rotate, which makes the water in the working chamber form a water ring under the action of centrifugal force. Ideally, the formed water ring is tangential to the impeller hub on the upper side and contact with the top of the blade on the lower side. Thus, a one-month conodont space is formed between the inner surface of the water ring and the impeller hub, which is divided into several elementary volumes of different sizes and dissimilarities by the impeller blades. When the motor drives the impeller to rotate, the volume of the elementary unit on the suction side increases from small to large, the pressure decreases gradually, and the gas is absorbed from the suction port; on the exhaust side, the volume of the elementary unit decreases from large to small, the gas is compressed and the pressure increases gradually; when the gas is compressed to a certain extent and connected with the exhaust port, the gas will be discharged. At the same time, a part of the water is taken out. In order to compensate for the loss of water, the Liquid Ring Vacuum Pump needs to continuously supplement the working water when it works, so the shape of the water ring remains basically unchanged, and it can absorb the heat generated by the compressed gas in time, so the process of compressed gas can also be regarded as an isothermal process.

Water ring vacuum pump

In summary, the three processes of suction, compression and exhaust of Liquid Ring Vacuum Pump are realized by the change of elementary volume in pump chamber, so it belongs to variable volume vacuum pump.

Liquid Ring Vacuum Pump Structural Composition

The main structure of Liquid Ring Vacuum Pump includes pump body, impeller, disc, bearing body, bearing cover, gas distributor, intake port, outlet, suction port, exhaust port and shaft seal. The shell is divided into two parts: the front shell and the rear shell; the suction and exhaust ports are all on the disc. The impeller blade of the Liquid Ring Vacuum Pump is of forward bending type, which can make the working liquid obtain greater kinetic energy, and is beneficial to the formation of the water ring.

When the Liquid Ring Vacuum Pump works, water enters the pump chamber with a certain pressure to form a water ring. At the same time, water is continuously discharged from the exhaust port under the entrainment of gas. After separation by gas-liquid separator, gas is discharged and water can be circulated after cooling.

Liquid Ring Vacuum Pump Characteristics

Compared with other types of vacuum pumps, Liquid Ring Vacuum Pumps have the following advantages:

1.The structure is simple, the requirement of manufacturing accuracy is low, and the processing method is simple.

2.Compact structure, high pump speed, can be directly connected with the motor without deceleration device, with a smaller structure size, can also obtain a larger exhaust volume, occupy a small area.

3.The process of compressed gas is basically isothermal, that is, the process temperature of compressed gas changes very little.

4.Because there is no metal friction surface in the pump chamber and the wear is very small, there is no need for lubrication. The sealing between the rotating parts and the fixing parts can be accomplished directly by water seal, which does not pollute the environment.

Inhalation uniformity, simple operation, convenient maintenance, stable and reliable work.

Liquid Ring Vacuum Pump also has its shortcomings:

(1) Low efficiency, generally around 35%, better up to 45%-50%.
(2) The ultimate vacuum is lower. This is mainly due to the structure of the Liquid Ring Vacuum Pump and the saturated vapor pressure of the working liquid. When water is used as working liquid, the limit vacuum can only reach 2000-4000Pa, while when oil is used as working liquid, the limit pressure can reach 130Pa.

In a word, because the process of gas compression in Liquid Ring Vacuum Pump is approximately isothermal, flammable and explosive gases can be removed. At the same time, due to the absence of exhaust valves and friction surfaces, dust-laden gases, condensable gases and gas-water mixtures can be removed.

If you want to know more about our vacuum pump products, or if you want to customize the Liquid Ring Vacuum Pump, please leave a message or send an email to

Contact us

If possible, kindly suggest please your working industry/process, working pressure, working medium, etc. Given detailed request helps to gain better-matched customized solution. Thanks for your patience.

your request will be responsed within 3 hours, kindly pay attention to your email please.


dry screw vacuum pump in wood processing industry

Posted on Tue, 01 Feb 2022 07:02:47 +0000

Explosion proof and high temperature resistant vacuum unit

Posted on Wed, 10 Nov 2021 07:30:11 +0000

vacuum pumps for chemical industry has high requirements

Posted on Mon, 08 Nov 2021 08:52:52 +0000

What are the applications of roots vacuum units in medicine?

Posted on Wed, 03 Nov 2021 07:57:18 +0000

The advantages of dry screw vacuum pumps make up for the disadvantages of oil-sealed vacuum pumps

Posted on Tue, 02 Nov 2021 09:05:35 +0000

dry vacuum pump for measures to avoid oil return

Posted on Thu, 28 Oct 2021 09:03:25 +0000