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一、引言 众所周知,迄今国内外所使用的各种真空泵,对于不同的气体都存在着选择性抽气作用。也就是说,直到目前为止,还找不到一种能够对所有气体(包括蒸气)都有相同的抽气效果的泵。只是各种不同的真空泵对各种不同的气体。其抽气原理不同。就具有不同的选择性罢了。因此为了在一个真空系统中获得好的抽气效果和极限真空度。一般却采用几种不同原理的泵联合抽气。尽管如此,效果总还不是最佳,从各种金属真空系统中残余气体的分析得知。H_2气在残余气体分压中均占有相当大的比例。因此从极限压强的角度来说,H_2上极限压强的重要限制因素,特别是高真空和极高真空范围就更是如此
I. INTRODUCTION It is well known that the various vacuum pumps used at home and abroad so far have a selective suction effect for different gases. That is to say, until now, a pump that has the same pumping effect on all gases (including steam) can not be found. Just a variety of different vacuum pumps for different gases. The suction principle is different. It has a different selectivity. So in order to get a good vacuum in a vacuum system and ultimate vacuum degree. In general there are several different principles of pump pumping. In spite of this, the effect is not always optimal, as we know from the analysis of residual gases in various metal vacuum systems. H 2 gas in the residual gas partial pressure are a considerable proportion. Therefore, from the point of view of ultimate pressure, an important limiting factor for the ultimate pressure on H 2, especially for high vacuum and very high vacuum ranges