(1) Thaum lub piston pas nrig thiab lub thawv ntim khoom tau sib sau ua ke, muaj qhov deflection, uas ua rau muaj kev sib txhuam hauv zos, thiab yuav tsum tau kho raws sijhawm;
(2) Lub caij nplooj ntoos hlav tuav ntawm lub nplhaib sealing yog nruj heev thiab kev sib txhuam quab yuam loj, yog li nws yuav tsum tau kho kom haum;
(3) Lub axial clearance ntawm lub nplhaib sealing yog me heev, thiab axial clearance yuav tsum tau kho raws li cov kev cai;
(4) Tus nqi ntawm cov roj muab tsis txaus, thiab cov roj yuav tsum tau nce kom tsim nyog;
(5) Kev khiav-hauv ntawm tus pas nrig piston thiab lub nplhaib sib khi tsis zoo, thiab kev khiav-hauv yuav tsum muaj zog thaum sib tsoo;
(6) Cov impurities yog tov nrog roj thiab roj, uas yuav tsum tau muab ntxuav kom huv si.
