1、液壓密封(feng)件之形(xing)式(shi)選擇(ze)

　　在液(ye)壓系統中，常見的密(mi)(mi)(mi)封(feng)(feng)形式有擠壓型(xing)O形密(mi)(mi)(mi)封(feng)(feng)圈(quan)(quan)(quan)(quan)(quan)(quan)、Y形圈(quan)(quan)(quan)(quan)(quan)(quan)、V形圈(quan)(quan)(quan)(quan)(quan)(quan)、U形圈(quan)(quan)(quan)(quan)(quan)(quan)唇(chun)形密(mi)(mi)(mi)封(feng)(feng)。唇(chun)形密(mi)(mi)(mi)封(feng)(feng)圈(quan)(quan)(quan)(quan)(quan)(quan)主要用(yong)(yong)于往復(fu)動密(mi)(mi)(mi)封(feng)(feng)，與O形圈(quan)(quan)(quan)(quan)(quan)(quan)等擠壓密(mi)(mi)(mi)封(feng)(feng)相比，往復(fu)動密(mi)(mi)(mi)封(feng)(feng)使用(yong)(yong)唇(chun)形密(mi)(mi)(mi)封(feng)(feng)圈(quan)(quan)(quan)(quan)(quan)(quan)具有更好的綜合性能(neng)和更長的使用(yong)(yong)壽命。

　　唇形(xing)密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)(feng)(feng)(feng)圈(quan)(quan)的(de)(de)(de)(de)密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)(feng)(feng)(feng)壓(ya)(ya)(ya)緊力(li)(li)是隨(sui)介質(zhi)壓(ya)(ya)(ya)力(li)(li)的(de)(de)(de)(de)改變(bian)(bian)而變(bian)(bian)化的(de)(de)(de)(de)，工作(zuo)中(zhong)始(shi)終應監控(kong)介質(zhi)壓(ya)(ya)(ya)力(li)(li)的(de)(de)(de)(de)變(bian)(bian)化，即能保證足(zu)夠的(de)(de)(de)(de)密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)(feng)(feng)(feng)壓(ya)(ya)(ya)緊力(li)(li)，又不至(zhi)于產(chan)生(sheng)過大(da)(da)(da)的(de)(de)(de)(de)摩擦(ca)力(li)(li)，擠壓(ya)(ya)(ya)性密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)(feng)(feng)(feng)主要靠預(yu)(yu)壓(ya)(ya)(ya)緊力(li)(li)產(chan)生(sheng)密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)(feng)(feng)(feng)力(li)(li)，密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)(feng)(feng)(feng)圈(quan)(quan)接(jie)觸壓(ya)(ya)(ya)力(li)(li)預(yu)(yu)先給(gei)定，工作(zuo)中(zhong)不能根據介質(zhi)壓(ya)(ya)(ya)力(li)(li)的(de)(de)(de)(de)改變(bian)(bian)而變(bian)(bian)化。大(da)(da)(da)的(de)(de)(de)(de)預(yu)(yu)壓(ya)(ya)(ya)力(li)(li)會使密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)(feng)(feng)(feng)圈(quan)(quan)與密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)(feng)(feng)(feng)面(mian)(mian)接(jie)觸面(mian)(mian)積增大(da)(da)(da)，產(chan)生(sheng)很大(da)(da)(da)的(de)(de)(de)(de)摩擦(ca)阻力(li)(li)，過大(da)(da)(da)的(de)(de)(de)(de)摩擦(ca)力(li)(li)會造成密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)(feng)(feng)(feng)圈(quan)(quan)的(de)(de)(de)(de)破損，在(zai)低壓(ya)(ya)(ya)時造成啟動(dong)困(kun)難，或產(chan)生(sheng)爬(pa)行(xing)現象，唇形(xing)密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)(feng)(feng)(feng)圈(quan)(quan)可以通(tong)過唇部撐開(kai)，變(bian)(bian)形(xing)補償小的(de)(de)(de)(de)磨損量，保證密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)(feng)(feng)(feng)效果(guo)和密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)(feng)(feng)(feng)壽(shou)命(ming);而O形(xing)圈(quan)(quan)隨(sui)著(zhu)摩擦(ca)余(yu)量的(de)(de)(de)(de)減少，直接(jie)影響其密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)(feng)(feng)(feng)性。

　　2、液壓密封件之(zhi)材料選擇

　　密(mi)封件(jian)形式(shi)和(he)(he)結(jie)構現(xian)在一(yi)般(ban)已經定型，各(ge)密(mi)封件(jian)質(zhi)量區(qu)別主(zhu)要在于(yu)制作(zuo)材料(liao)上。密(mi)封材料(liao)主(zhu)要使用(yong)(yong)(yong)橡膠和(he)(he)合成樹(shu)脂。由于(yu)各(ge)種材料(liao)性(xing)(xing)能特點不(bu)同(tong)(tong)，性(xing)(xing)能特點不(bu)同(tong)(tong)，用(yong)(yong)(yong)途也就有(you)所不(bu)同(tong)(tong)。選(xuan)用(yong)(yong)(yong)時需(xu)根據不(bu)同(tong)(tong)的(de)(de)(de)(de)使用(yong)(yong)(yong)條(tiao)件(jian)和(he)(he)不(bu)同(tong)(tong)的(de)(de)(de)(de)使用(yong)(yong)(yong)條(tiao)件(jian)作(zuo)出(chu)合適的(de)(de)(de)(de)選(xuan)擇。另(ling)外，某一(yi)材質(zhi)的(de)(de)(de)(de)密(mi)封對被(bei)密(mi)封的(de)(de)(de)(de)某一(yi)工(gong)作(zuo)介(jie)質(zhi)(如礦物(wu)油等)表現(xian)較好的(de)(de)(de)(de)密(mi)封性(xing)(xing)能，而對另(ling)一(yi)介(jie)質(zhi)表現(xian)極差，這就是(shi)密(mi)封材料(liao)與(yu)液壓油的(de)(de)(de)(de)相容性(xing)(xing)。還有(you)，各(ge)種不(bu)同(tong)(tong)的(de)(de)(de)(de)密(mi)封材料(liao)對你不(bu)同(tong)(tong)的(de)(de)(de)(de)工(gong)作(zuo)條(tiao)件(jian)表現(xian)出(chu)不(bu)同(tong)(tong)的(de)(de)(de)(de)性(xing)(xing)能。有(you)些(xie)耐熱，有(you)些(xie)不(bu)耐熱;有(you)些(xie)耐酸(suan)，有(you)些(xie)耐堿，有(you)些(xie)耐水，有(you)些(xie)耐油;有(you)些(xie)抗熱，有(you)些(xie)耐低溫，有(you)些(xie)耐高溫，等等。這些(xie)因素在考慮密(mi)封件(jian)材料(liao)的(de)(de)(de)(de)時候需(xu)注意(yi)。