First, the determination of the type of water ring vacuum pump
The type of water ring vacuum pump is mainly determined by the pumped medium, the air volume required for the work, the degree of vacuum or the exhaust pressure.

There are two points that need to be paid attention to after the water ring vacuum pump is working normally:
1. As far as possible, the vacuum degree of the selected vacuum pump is required to be within the high-efficiency range, that is, the operation in the area of ​​the critical required vacuum degree or the critical required exhaust pressure, so as to ensure that the vacuum pump can work normally according to the required conditions and requirements. . Operation near the maximum vacuum or maximum discharge pressure range of the vacuum pump should be avoided. Operating in this area is not only extremely inefficient, but also very unstable, which easily causes the vacuum pump to generate vibration and noise. For a vacuum pump with a high degree of vacuum, cavitation often occurs when operating in this area. The obvious phenomenon that causes this phenomenon is the noise and vibration in the vacuum pump. Excessive cavitation will cause damage to the pump body, impeller and other parts, so that the vacuum pump cannot work normally.

It can be seen from this that when the vacuum degree or gas pressure required by the vacuum pump is not high, it can be preferentially selected in the single-stage pump. If the requirements for vacuum degree or exhaust pressure are high, the single-stage pump often cannot meet it, or the pump is required to still have a large air volume under the condition of higher vacuum degree, that is, the performance curve is required to be flat at higher vacuum degree. Use a two-stage pump. If the vacuum degree is required to be above -710mmHg, the Roots water ring vacuum unit can be selected as the vacuum pumping device.

2. Correctly select the vacuum pump according to the pumping volume required by the system
If the type of vacuum pump or vacuum unit is selected, it is also necessary to select the correct model according to the pumping volume required by the system.