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Things to know about vacuum pump

The vacuum pump is a type of equipment that is used to acquire a vacuum in a closed container. The device reduces the liquid pressure, gradually draws the air molecules from a sealed volume so that vacuum can form in that closed space.

There are many types of vacuum pumps available for different needs, they are; mainly classified into three categories, according to their types and use but they all serve a similar purpose that is; remove air, vapor, or gases from a closed space.

While choosing a vacuum pump there are several factors which you must take into account. Knowing everything about pumps can help you in meeting your requirements.

Type of vacuum pump to use

As we already know there are different types of a vacuum pump which serves a distinct purpose. Before buying, analyze your use, note down what all you want and intend to use in it, this can lead you to the correct type according to your benefit.

Positive displacement 

Positive displacement pumps are used to create a low vacuum. It uses a mechanism that expands the cavity, permits the gases to flow out, closes the cavity, and exhausts the air molecules into the atmosphere. 

Liquid ring vacuum pump

A liquid ring vacuum pump is used as a gas compressor. It compresses gas by rotating a rotor (which increases the pressure and flow of fluid), it forms a compression chamber. The pump is commonly used for the extraction of gas, vapor, moisture, etc from a closed space.

Momentum transfer pump

Momentum transfer pumps are also known as molecular pumps. They accelerate gas molecules from the vacuum side to the exhaust side. This pump gusts out the diffused air or gas molecules through a jet of oil or speed fans.

Root vacuum pump

A roots vacuum pump is a mechanical vacuum pump where soled rotors swing simultaneously and rapidly. 

Entrapment pump

An entrapment pump uses cold temperature to change the air molecules into a solid-state. The pump usage chemicals, which react with air molecules to give a solid residue.

Rotary vane pump

A rotary vane pump is the most commonly used pump, this consists of a vane mounted to the rotor which rotates inside the cavity. They are used as high-pressure hydraulic pumps in automobiles, air conditioning, etc. Mid-range pressure pumps are used in soft drink dispensers and coffee machines. 

Regenerative pump

This pump utilizes the vortex action of the fluid. It consists of various sets of teeth perpendicular to the rotor, the rotor circulates air molecules inside a static hollow aperture. They are used in load lock in manufacturing processes. 

Vacuum level

Vacuum level varies in all types of pumps. It became very important to know your vacuum level requirements beforehand. The selection majorly depends on the level of vacuum that needs to be obtained for the work. The levels are categorized into five categories; rough vacuum, extremely high vacuum, ultra-high vacuum, high vacuum, and medium vacuum.

The flow rate of the pump

Flow rate means the volume of gas displaced by the pump at a specific time. Analyze the flow rate of the pump, this can help in ensuring the pump has adequate pumping speed at the working vacuum.

Requirement of Lubricant

Different vacuum pumps require different kinds of lubricants for their smooth and efficient functioning. Lubrication allows the pump’s elements to work with lower friction; it also helps to attain the required vacuum level. 

Lubrication not just enhances efficiency but also increases the lifespan of the pump.

Requirement of power 

Power is another key factor for efficiency and to determine the cost as well.

Pumps require power for the operation, all pumps have a different power consumption rate. The change in power can affect the speed and result. Moreover, power consumption is also essential to determine the running cost.

Evacuation Time

The time required by the pump to create a vacuum in the required system is known as evacuation time. The time varies on the application, some require long evacuation whereas some require short.


The temperature has a direct impact on the performance of the pump. The vacuum pump usually operates at 5°-14°C, a temperature higher than that might indicate a problem.


Everything lasts long if it is well maintained, similarly pumps require maintenance for better function and durability, there are certain things you should keep in mind to increase the life of the pump.

Keep checking on the oil level from the sight glass present on the side of the pump. If the oil level is low, refill the oil carefully, avoid overfilling. Too much and too little oil in the pump might raise serious issues.

While replacing the pump oil, be cautious! If you are using the correct oil. Every pump has different oil requirements. Make sure you are using the proper recommended oil for that pump.

Keep on checking the motor’s rotating direction, the motor should always rotate in the correct direction. The direction is often marked on the motor by an arrow, if the rotation is wrong quickly stop or restart the motor.

Keep an eye on the vane, the vanes in the pump should be examined annually. A crack or worn areas should be replaced.

Get and understand your pump, know everything about your required pump at the China vacuum pump. Contact us 0039 320 461391.