How to select the vacuum pump, vacuum pump steps, vacuum pump method

1. Vacuum pump working pressure should satisfy the limit of vacuum equipment vacuum and work pressure requirements. For example, if the vacuum drying process requires vacuum degree of work for 10 mmHg, the vacuum degree of vacuum pump should be selected for at least 2 mmHg, best to 1 mmHg. Usually the limiting vacuum pump selection for an order of magnitude than half high vacuum degree of vacuum equipment.

2。 Correct selection of vacuum pump working point. Each pump has a certain working pressure range, for example: 2 bv series water ring vacuum pump working pressure in the range of 760 MMHG ~ 25 MMHG ( Absolute pressure) , in such a wide range of pressure, the pumping speed of the pump with pressure changes ( Detailed change) 。 Its stable working pressure range is 760 ~ 60 MMHG. As a result, the working point of the pump should be within the scope of the choice, and should not be under the condition of 25 ~ 30 MMHG work long hours.

3。 Under the working pressure, vacuum pump should be able to remove all gas produced in the process of vacuum equipment.

4。 The right combination vacuum pump. Due to the vacuum pump with selective pumping function, therefore sometimes a pump cannot meet the pumping requirements, so you need to combine multiple pump to complement each other to meet the pumping requirements. For example, titanium sublimation pump suction of hydrogen velocity is very high, but can't be suction, and three pole sputtering ion pump ( Or the asymmetric between the cathode sputtering ion pump) For argon pumping speed. When used in combination, vacuum unit will have a better vacuum. In addition, some of the vacuum pump can't work under atmospheric pressure, vacuum need. Some vacuum pump outlet pressure below atmospheric pressure, so you need to pump before, so the pump must be grouped together.

5。 Vacuum equipment to oil pollution requirements. If strict equipment without oil, should choose a variety of oil pump, such as water ring pump, molecular sieve adsorption pump, sputter ion pump, cryogenic pump, etc. If not strict, should can choose to have a pump, plus some oil pollution measures, such as increasing cold trap, baffle, the oil well, etc. , can also meet the requirements of clean vacuum.

6。 Understand to pumping gas composition. The gas does not contain condensable vapor, dust and corrosion resistance. Choosing a vacuum pump, you need to know the gas composition and gas to choose the appropriate pump for pumping. If the gas contained in the steam, particles and corrosive gas, please consider auxiliary equipment installed in the inlet pipe of pump, such as condenser, dust collector, etc.

7。 In the vacuum pump oil vapor how to affect the environment? If you don't allow pollution environment, you can choose oil-free vacuum pump or the oil vapor emissions to the outside.

8。 Vacuum pump vibration of the work has no effect on the process and the environment. If the process is not allowed, please choose no vibration of the pump or vibration control measures.