Raws li ib qho ntawm reciprocating twj tso kua mis hom, plunger twj yog siv dav hauv cov roj av, tshuaj lom neeg, tsuas, hlau, thiab ntxuav cov lag luam. Nrog kev txhim kho thev naus laus zis, loj-ntws plunger twj tau ua kom pom cov twj tso kua mis zoo sib xws nrog cov twj siv hluav taws xob nrog cov twj tso kua mis.
Nyob rau hauv kev txhaj tshuaj dej kev txhaj tshuaj muaj cov twj tseem ceeb muaj lub zog tseem ceeb-txuag hluav taws xob zoo tshaj cov twj tso kua mis. Lub cev muaj zog-Direct-Tsav ntse plunger twj uas tau hloov kho cov khoom siv hluav taws xob, cov khoom siv sab nraud muaj qhov tsis muaj zog. Tsis tas li ntawd, nws tau nruab nrog cov tswv yim tswj hwm kom saib xyuas, tiv thaiv thiab ua ntej npaj kev ua txhaum los txo tus nqi ua haujlwm kom zoo.
Kev loj hlob ntawm lub cev muaj zog-Direct-tsav cov twj siv hluav taws xob tau ua kom muaj kev txuag hluav taws xob nrog cov roj hluav taws xob kev txhaj tshuaj uas muaj zog ntawm cov roj av txhaj tshuaj thiab ua tiav lub zog txuag hluav taws xob.