1、液壓密封件之(zhi)形(xing)式選擇(ze)

　　在液壓系統中(zhong)，常見的(de)密(mi)封形(xing)(xing)(xing)式(shi)有(you)擠壓型(xing)O形(xing)(xing)(xing)密(mi)封圈(quan)(quan)(quan)、Y形(xing)(xing)(xing)圈(quan)(quan)(quan)、V形(xing)(xing)(xing)圈(quan)(quan)(quan)、U形(xing)(xing)(xing)圈(quan)(quan)(quan)唇(chun)形(xing)(xing)(xing)密(mi)封。唇(chun)形(xing)(xing)(xing)密(mi)封圈(quan)(quan)(quan)主要用(yong)于(yu)往復(fu)動密(mi)封，與O形(xing)(xing)(xing)圈(quan)(quan)(quan)等(deng)擠壓密(mi)封相比，往復(fu)動密(mi)封使(shi)用(yong)唇(chun)形(xing)(xing)(xing)密(mi)封圈(quan)(quan)(quan)具有(you)更好的(de)綜合性能和更長的(de)使(shi)用(yong)壽命。

　　唇形密(mi)(mi)封(feng)(feng)(feng)圈(quan)(quan)(quan)的(de)(de)(de)(de)(de)密(mi)(mi)封(feng)(feng)(feng)壓(ya)(ya)(ya)(ya)緊力(li)(li)是隨介(jie)質壓(ya)(ya)(ya)(ya)力(li)(li)的(de)(de)(de)(de)(de)改(gai)變而(er)變化(hua)(hua)的(de)(de)(de)(de)(de)，工作(zuo)中始終應監控介(jie)質壓(ya)(ya)(ya)(ya)力(li)(li)的(de)(de)(de)(de)(de)變化(hua)(hua)，即能(neng)保證(zheng)足夠的(de)(de)(de)(de)(de)密(mi)(mi)封(feng)(feng)(feng)壓(ya)(ya)(ya)(ya)緊力(li)(li)，又(you)不(bu)至于產(chan)生過大(da)(da)的(de)(de)(de)(de)(de)摩(mo)(mo)擦(ca)力(li)(li)，擠壓(ya)(ya)(ya)(ya)性(xing)密(mi)(mi)封(feng)(feng)(feng)主要靠預壓(ya)(ya)(ya)(ya)緊力(li)(li)產(chan)生密(mi)(mi)封(feng)(feng)(feng)力(li)(li)，密(mi)(mi)封(feng)(feng)(feng)圈(quan)(quan)(quan)接(jie)(jie)觸(chu)壓(ya)(ya)(ya)(ya)力(li)(li)預先給定，工作(zuo)中不(bu)能(neng)根據介(jie)質壓(ya)(ya)(ya)(ya)力(li)(li)的(de)(de)(de)(de)(de)改(gai)變而(er)變化(hua)(hua)。大(da)(da)的(de)(de)(de)(de)(de)預壓(ya)(ya)(ya)(ya)力(li)(li)會(hui)使密(mi)(mi)封(feng)(feng)(feng)圈(quan)(quan)(quan)與密(mi)(mi)封(feng)(feng)(feng)面接(jie)(jie)觸(chu)面積(ji)增大(da)(da)，產(chan)生很大(da)(da)的(de)(de)(de)(de)(de)摩(mo)(mo)擦(ca)阻(zu)力(li)(li)，過大(da)(da)的(de)(de)(de)(de)(de)摩(mo)(mo)擦(ca)力(li)(li)會(hui)造成(cheng)密(mi)(mi)封(feng)(feng)(feng)圈(quan)(quan)(quan)的(de)(de)(de)(de)(de)破損，在低壓(ya)(ya)(ya)(ya)時造成(cheng)啟(qi)動困難(nan)，或產(chan)生爬行現象，唇形密(mi)(mi)封(feng)(feng)(feng)圈(quan)(quan)(quan)可以通(tong)過唇部撐開，變形補償小的(de)(de)(de)(de)(de)磨損量(liang)，保證(zheng)密(mi)(mi)封(feng)(feng)(feng)效果和(he)密(mi)(mi)封(feng)(feng)(feng)壽命;而(er)O形圈(quan)(quan)(quan)隨著摩(mo)(mo)擦(ca)余量(liang)的(de)(de)(de)(de)(de)減少，直接(jie)(jie)影響其密(mi)(mi)封(feng)(feng)(feng)性(xing)。

　　2、液壓密封件之材料選擇

　　密(mi)(mi)封(feng)(feng)(feng)件形式和(he)結(jie)構現(xian)在(zai)(zai)一(yi)般已經定型，各(ge)(ge)密(mi)(mi)封(feng)(feng)(feng)件質(zhi)量區(qu)別主(zhu)要在(zai)(zai)于制作材料(liao)(liao)(liao)上(shang)。密(mi)(mi)封(feng)(feng)(feng)材料(liao)(liao)(liao)主(zhu)要使(shi)用橡膠和(he)合(he)成樹脂(zhi)。由于各(ge)(ge)種(zhong)材料(liao)(liao)(liao)性(xing)(xing)能(neng)(neng)特(te)點不(bu)同(tong)(tong)(tong)(tong)(tong)(tong)，性(xing)(xing)能(neng)(neng)特(te)點不(bu)同(tong)(tong)(tong)(tong)(tong)(tong)，用途也就(jiu)有(you)(you)(you)(you)(you)(you)所不(bu)同(tong)(tong)(tong)(tong)(tong)(tong)。選用時需根據(ju)不(bu)同(tong)(tong)(tong)(tong)(tong)(tong)的(de)(de)(de)(de)使(shi)用條件和(he)不(bu)同(tong)(tong)(tong)(tong)(tong)(tong)的(de)(de)(de)(de)使(shi)用條件作出(chu)合(he)適的(de)(de)(de)(de)選擇(ze)。另外(wai)，某一(yi)材質(zhi)的(de)(de)(de)(de)密(mi)(mi)封(feng)(feng)(feng)對(dui)被密(mi)(mi)封(feng)(feng)(feng)的(de)(de)(de)(de)某一(yi)工作介質(zhi)(如礦物(wu)油(you)等(deng))表(biao)現(xian)較好(hao)的(de)(de)(de)(de)密(mi)(mi)封(feng)(feng)(feng)性(xing)(xing)能(neng)(neng)，而對(dui)另一(yi)介質(zhi)表(biao)現(xian)極差，這就(jiu)是(shi)密(mi)(mi)封(feng)(feng)(feng)材料(liao)(liao)(liao)與液壓油(you)的(de)(de)(de)(de)相容性(xing)(xing)。還有(you)(you)(you)(you)(you)(you)，各(ge)(ge)種(zhong)不(bu)同(tong)(tong)(tong)(tong)(tong)(tong)的(de)(de)(de)(de)密(mi)(mi)封(feng)(feng)(feng)材料(liao)(liao)(liao)對(dui)你不(bu)同(tong)(tong)(tong)(tong)(tong)(tong)的(de)(de)(de)(de)工作條件表(biao)現(xian)出(chu)不(bu)同(tong)(tong)(tong)(tong)(tong)(tong)的(de)(de)(de)(de)性(xing)(xing)能(neng)(neng)。有(you)(you)(you)(you)(you)(you)些(xie)耐(nai)(nai)熱(re)，有(you)(you)(you)(you)(you)(you)些(xie)不(bu)耐(nai)(nai)熱(re);有(you)(you)(you)(you)(you)(you)些(xie)耐(nai)(nai)酸，有(you)(you)(you)(you)(you)(you)些(xie)耐(nai)(nai)堿，有(you)(you)(you)(you)(you)(you)些(xie)耐(nai)(nai)水，有(you)(you)(you)(you)(you)(you)些(xie)耐(nai)(nai)油(you);有(you)(you)(you)(you)(you)(you)些(xie)抗熱(re)，有(you)(you)(you)(you)(you)(you)些(xie)耐(nai)(nai)低溫(wen)，有(you)(you)(you)(you)(you)(you)些(xie)耐(nai)(nai)高溫(wen)，等(deng)等(deng)。這些(xie)因素在(zai)(zai)考慮密(mi)(mi)封(feng)(feng)(feng)件材料(liao)(liao)(liao)的(de)(de)(de)(de)時候(hou)需注意。