1、液壓(ya)密封件之形(xing)式選擇

　　在液壓系統中，常見的密(mi)封(feng)(feng)(feng)形(xing)(xing)(xing)式有擠壓型O形(xing)(xing)(xing)密(mi)封(feng)(feng)(feng)圈、Y形(xing)(xing)(xing)圈、V形(xing)(xing)(xing)圈、U形(xing)(xing)(xing)圈唇(chun)形(xing)(xing)(xing)密(mi)封(feng)(feng)(feng)。唇(chun)形(xing)(xing)(xing)密(mi)封(feng)(feng)(feng)圈主要用于往復(fu)動(dong)密(mi)封(feng)(feng)(feng)，與O形(xing)(xing)(xing)圈等擠壓密(mi)封(feng)(feng)(feng)相比，往復(fu)動(dong)密(mi)封(feng)(feng)(feng)使(shi)用唇(chun)形(xing)(xing)(xing)密(mi)封(feng)(feng)(feng)圈具(ju)有更(geng)好的綜合性能和更(geng)長的使(shi)用壽命。

　　唇形(xing)密(mi)封(feng)(feng)(feng)圈(quan)(quan)的(de)密(mi)封(feng)(feng)(feng)壓(ya)緊(jin)力(li)(li)(li)是隨介(jie)質壓(ya)力(li)(li)(li)的(de)改變而變化的(de)，工(gong)作中始(shi)終(zhong)應監控介(jie)質壓(ya)力(li)(li)(li)的(de)變化，即能保(bao)證(zheng)足夠的(de)密(mi)封(feng)(feng)(feng)壓(ya)緊(jin)力(li)(li)(li)，又不至于產生過大(da)的(de)摩(mo)(mo)擦(ca)(ca)力(li)(li)(li)，擠壓(ya)性(xing)密(mi)封(feng)(feng)(feng)主要靠預(yu)(yu)壓(ya)緊(jin)力(li)(li)(li)產生密(mi)封(feng)(feng)(feng)力(li)(li)(li)，密(mi)封(feng)(feng)(feng)圈(quan)(quan)接(jie)觸壓(ya)力(li)(li)(li)預(yu)(yu)先給定(ding)，工(gong)作中不能根據(ju)介(jie)質壓(ya)力(li)(li)(li)的(de)改變而變化。大(da)的(de)預(yu)(yu)壓(ya)力(li)(li)(li)會(hui)使密(mi)封(feng)(feng)(feng)圈(quan)(quan)與密(mi)封(feng)(feng)(feng)面(mian)接(jie)觸面(mian)積增(zeng)大(da)，產生很大(da)的(de)摩(mo)(mo)擦(ca)(ca)阻力(li)(li)(li)，過大(da)的(de)摩(mo)(mo)擦(ca)(ca)力(li)(li)(li)會(hui)造成(cheng)密(mi)封(feng)(feng)(feng)圈(quan)(quan)的(de)破損，在低壓(ya)時造成(cheng)啟動(dong)困難，或產生爬行(xing)現象，唇形(xing)密(mi)封(feng)(feng)(feng)圈(quan)(quan)可以(yi)通(tong)過唇部(bu)撐開，變形(xing)補償小的(de)磨損量，保(bao)證(zheng)密(mi)封(feng)(feng)(feng)效果和密(mi)封(feng)(feng)(feng)壽(shou)命;而O形(xing)圈(quan)(quan)隨著摩(mo)(mo)擦(ca)(ca)余量的(de)減少，直接(jie)影(ying)響其密(mi)封(feng)(feng)(feng)性(xing)。

　　2、液壓密封件(jian)之(zhi)材料選擇

　　密(mi)封(feng)(feng)件形(xing)式和結構現(xian)(xian)在(zai)一般已經定(ding)型(xing)，各(ge)(ge)密(mi)封(feng)(feng)件質(zhi)量(liang)區別主(zhu)(zhu)要在(zai)于制作(zuo)(zuo)材(cai)料(liao)上。密(mi)封(feng)(feng)材(cai)料(liao)主(zhu)(zhu)要使用(yong)橡(xiang)膠和合成(cheng)樹脂。由于各(ge)(ge)種(zhong)材(cai)料(liao)性(xing)(xing)能特點不(bu)(bu)(bu)(bu)同(tong)(tong)，性(xing)(xing)能特點不(bu)(bu)(bu)(bu)同(tong)(tong)，用(yong)途也就(jiu)有(you)(you)(you)所不(bu)(bu)(bu)(bu)同(tong)(tong)。選用(yong)時(shi)需根(gen)據不(bu)(bu)(bu)(bu)同(tong)(tong)的(de)使用(yong)條(tiao)件和不(bu)(bu)(bu)(bu)同(tong)(tong)的(de)使用(yong)條(tiao)件作(zuo)(zuo)出(chu)合適的(de)選擇。另外，某一材(cai)質(zhi)的(de)密(mi)封(feng)(feng)對被密(mi)封(feng)(feng)的(de)某一工作(zuo)(zuo)介質(zhi)(如礦物油(you)等)表現(xian)(xian)較好的(de)密(mi)封(feng)(feng)性(xing)(xing)能，而對另一介質(zhi)表現(xian)(xian)極差，這就(jiu)是密(mi)封(feng)(feng)材(cai)料(liao)與液壓油(you)的(de)相容性(xing)(xing)。還有(you)(you)(you)，各(ge)(ge)種(zhong)不(bu)(bu)(bu)(bu)同(tong)(tong)的(de)密(mi)封(feng)(feng)材(cai)料(liao)對你(ni)不(bu)(bu)(bu)(bu)同(tong)(tong)的(de)工作(zuo)(zuo)條(tiao)件表現(xian)(xian)出(chu)不(bu)(bu)(bu)(bu)同(tong)(tong)的(de)性(xing)(xing)能。有(you)(you)(you)些(xie)(xie)耐(nai)熱(re)，有(you)(you)(you)些(xie)(xie)不(bu)(bu)(bu)(bu)耐(nai)熱(re);有(you)(you)(you)些(xie)(xie)耐(nai)酸，有(you)(you)(you)些(xie)(xie)耐(nai)堿，有(you)(you)(you)些(xie)(xie)耐(nai)水，有(you)(you)(you)些(xie)(xie)耐(nai)油(you);有(you)(you)(you)些(xie)(xie)抗熱(re)，有(you)(you)(you)些(xie)(xie)耐(nai)低(di)溫，有(you)(you)(you)些(xie)(xie)耐(nai)高溫，等等。這些(xie)(xie)因素在(zai)考慮(lv)密(mi)封(feng)(feng)件材(cai)料(liao)的(de)時(shi)候(hou)需注(zhu)意(yi)。