Two aspects should be paid attention to according to different vacuum pump models
According to the above criteria, 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 vacuum degree or exhaust pressure is high, the single-stage pump is usually not satisfied. Perhaps, the requesting pump still has a large amount of gas under the condition of high vacuum degree, that is, the requesting performance curve is relatively flat under the condition of high vacuum degree, so the two-stage pump can be selected.
According to different vacuum pump models, the following two aspects should be paid attention to when the vacuum pump is working:
1. Operation near the maximum vacuum or exhaust pressure shall be avoided. In this area, not only the efficiency is very low, but also the work is very unstable, easy to produce vibration and noise. If it is only used for vacuum pump, it is better to choose single effect pump. The single effect pump is simple in structure, simple in manufacture and protection, and has good cavitation resistance under high vacuum.
2. As far as possible, the water ring vacuum pump is required to operate in the high efficiency area, that is, in the area of critical vacuum degree or critical exhaust pressure.
If it is only used for compressor with larger air volume, it is suitable to select double effect pump for comparison. Due to the large air volume, small volume and light weight of the double effect pump, the radial force can be actively balanced, the shaft is not simply fatigued and cracked, and the service life of the water ring pump is longer. For Schindler vacuum pump with high vacuum degree, cavitation often occurs when it operates in this area. The obvious sign of this phenomenon is that there is noise and vibration in the pump.
Cavitation will cause damage to pump body, impeller and other parts, so that the pump can not work. If the vacuum degree is more than – 710mmhg, water ring air pump or water ring roots vacuum unit can be selected as vacuum pumping equipment.