前qian級ji泵beng和he後hou級ji泵beng有you些xie差cha別bie，後hou級ji泵beng的de泵beng腔qiang比bi前qian級ji泵beng大da，這zhe是shi因yin為wei泵beng的de抽chou速su主zhu要yao決jue定ding於yu後hou級ji泵beng的de有you效xiao幾ji何he容rong積ji。另ling外wai，前qian級ji泵beng和he單dan級ji旋xuan片pian泵beng一yi樣yang，隨sui時shi有you油you進jin入ru泵beng腔qiang;erhoujibengjinzaikaishigongzuoshiyoushaoliangdeyou，gongzuoyiduanshiwenhou，bianmeiyouyoujinrubengqiangle，zheshiyinweihoujimeiyouzhuanmendeyoulu。zheyangzuobingbuhuiyingxianghoujibengdexingneng，yinweichouqishijianyichang，houjibengjinqikoudeyaqiangdadaxiajiang，ertadechukouyaqiangyehenxiao，jinchukoudeyaqiangchabuda，beiyasuoqitijifengxifanliudelianghenshao，tongshi，zaizhenkongdujiaogaodeqingkuangxia，fengxideliuzujiaoda，suiranmeiyouyoumifeng，danfanliudeqitiliangyehenshao。xiangfan，youruxiahaochu:可以避免泵油把氣體和蒸氣帶進後級進氣口，從而大大地降低了殘餘氣體的分壓強；同tong時shi，由you於yu後hou級ji泵beng中zhong油you的de輕qing餾liu分fen不bu斷duan地di被bei前qian級ji泵beng抽chou走zou，殘can餘yu的de油you蒸zheng氣qi分fen壓ya強qiang也ye降jiang低di了le，這zhe就jiu使shi泵beng的de極ji限xian真zhen空kong得de到dao了le提ti高gao。氣qi分fen壓ya強qiang也ye降jiang低di了le，這zhe代dai使shi泵beng的de極ji限xian真zhen空kong得de到dao了le提ti高gao。
