Vacuum technology has important use in the numerical simulation of space, because of the space simulator on being the container from several thousand cubic meters to tens of thousands of cubic meters, the volume of vacuum degree change from tens of thousands of Pa to several Pa, and is pumped gas contains a large amount of water vapor or part of the nitrogen oxide, so this kind of vacuum system first problem is the pre vacuum problems, what type of vacuum pump shall be equipped with vacuum system? This paper analyzes the selection and use of vacuum pump in space simulator.
Traditionally, the slide valve pump is used as the front stage pump. There are many disadvantages in choosing slide valve pump. First, the slide valve pump runs for a long time under high inlet pressure. Secondly, because there are a lot of water vapor or nitrogen oxide in the pumped gas, once these gases enter the pump, the vacuum pump oil will be emulsified and deteriorated rapidly, and the sealing of the oil will be damaged, leading to the deterioration of the vacuum performance, or even the destruction of the pump; Third, the number of pumps need to be configured, and slide valve pump vibration, noise is also large.
Screw vacuum pump can be used in the selection. Screw vacuum pump has become the preferred product of large space simulation vacuum system due to its advantages of clean and oil-free, high pumping speed, low vibration and low noise. In addition, in order to improve the pumping speed and limit vacuum of the vacuum unit and reduce the size of screw pump accordingly, it is generally adopted a two-stage unit consisting of one Roots pump and screw vacuum pump in series or a three-stage unit consisting of two Roots pump and screw vacuum pump in series. To prevent particles and impurities from entering the pump, inlet filters with an accuracy of 50 m are installed at the inlet of the vacuum unit.
Screw vacuum pump placement for environmental requirements
Work in a comfortable environment for work of equipment and its application effect are helpful in the placement of dry screw vacuum pump on the surrounding environment has certain requirements and this is also one of the ways in which to ensure the service life of equipment in the environment of the is not suitable for the normal operation of the equipment of this very small on the one hand, if therefore affect the service life of the equipment that is not good.
1. The ambient temperature of the equipment shall not exceed 45 degrees.
2, dry screw vacuum pump should be placed horizontally.
3. Ensure the stability of screw vacuum pump base or mounting bracket during equipment installation.
4, should be set aside in advance maintenance space and dry screw vacuum pump and the wall should have at least 1 meter distance between each other to leave a channel in advance to facilitate maintenance and maintenance.
5, the installation site should be spacious dust less lighting good to ensure that dry screw vacuum pump can be sufficient cooling and the relative humidity of the air should also be low for easy operation and maintenance.
In the installation of dry screw vacuum pump, should pay attention to the choice of installation environment, that is, to ensure that screw vacuum pump equipment in the later period can be applied.