1、液壓密封件(jian)之形式(shi)選擇

　　在液壓(ya)系統中，常見(jian)的密(mi)封(feng)(feng)(feng)形(xing)(xing)(xing)式有擠壓(ya)型O形(xing)(xing)(xing)密(mi)封(feng)(feng)(feng)圈(quan)、Y形(xing)(xing)(xing)圈(quan)、V形(xing)(xing)(xing)圈(quan)、U形(xing)(xing)(xing)圈(quan)唇形(xing)(xing)(xing)密(mi)封(feng)(feng)(feng)。唇形(xing)(xing)(xing)密(mi)封(feng)(feng)(feng)圈(quan)主(zhu)要用于往復動密(mi)封(feng)(feng)(feng)，與O形(xing)(xing)(xing)圈(quan)等擠壓(ya)密(mi)封(feng)(feng)(feng)相比(bi)，往復動密(mi)封(feng)(feng)(feng)使(shi)用唇形(xing)(xing)(xing)密(mi)封(feng)(feng)(feng)圈(quan)具有更(geng)(geng)好(hao)的綜合(he)性能和(he)更(geng)(geng)長的使(shi)用壽命。

　　唇(chun)(chun)(chun)形密(mi)封(feng)(feng)(feng)圈(quan)的(de)(de)(de)密(mi)封(feng)(feng)(feng)壓(ya)(ya)(ya)緊(jin)(jin)力(li)(li)是隨介(jie)質壓(ya)(ya)(ya)力(li)(li)的(de)(de)(de)改(gai)變(bian)而(er)(er)變(bian)化的(de)(de)(de)，工作(zuo)中(zhong)始(shi)終(zhong)應監(jian)控介(jie)質壓(ya)(ya)(ya)力(li)(li)的(de)(de)(de)變(bian)化，即能保(bao)(bao)證足夠的(de)(de)(de)密(mi)封(feng)(feng)(feng)壓(ya)(ya)(ya)緊(jin)(jin)力(li)(li)，又不至(zhi)于(yu)產生過(guo)大(da)(da)的(de)(de)(de)摩擦力(li)(li)，擠壓(ya)(ya)(ya)性(xing)密(mi)封(feng)(feng)(feng)主要靠預(yu)壓(ya)(ya)(ya)緊(jin)(jin)力(li)(li)產生密(mi)封(feng)(feng)(feng)力(li)(li)，密(mi)封(feng)(feng)(feng)圈(quan)接(jie)觸壓(ya)(ya)(ya)力(li)(li)預(yu)先給定，工作(zuo)中(zhong)不能根據介(jie)質壓(ya)(ya)(ya)力(li)(li)的(de)(de)(de)改(gai)變(bian)而(er)(er)變(bian)化。大(da)(da)的(de)(de)(de)預(yu)壓(ya)(ya)(ya)力(li)(li)會(hui)使密(mi)封(feng)(feng)(feng)圈(quan)與(yu)密(mi)封(feng)(feng)(feng)面接(jie)觸面積增大(da)(da)，產生很大(da)(da)的(de)(de)(de)摩擦阻力(li)(li)，過(guo)大(da)(da)的(de)(de)(de)摩擦力(li)(li)會(hui)造(zao)成(cheng)密(mi)封(feng)(feng)(feng)圈(quan)的(de)(de)(de)破損(sun)，在低壓(ya)(ya)(ya)時造(zao)成(cheng)啟(qi)動困難，或產生爬行(xing)現象，唇(chun)(chun)(chun)形密(mi)封(feng)(feng)(feng)圈(quan)可以通(tong)過(guo)唇(chun)(chun)(chun)部撐開，變(bian)形補償小的(de)(de)(de)磨損(sun)量(liang)(liang)，保(bao)(bao)證密(mi)封(feng)(feng)(feng)效果和密(mi)封(feng)(feng)(feng)壽(shou)命;而(er)(er)O形圈(quan)隨著摩擦余量(liang)(liang)的(de)(de)(de)減少(shao)，直接(jie)影響其密(mi)封(feng)(feng)(feng)性(xing)。

　　2、液壓密封件之(zhi)材料(liao)選(xuan)擇

　　密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)件形(xing)式和(he)結構現在(zai)一(yi)般已經定型，各(ge)密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)件質量區別(bie)主要在(zai)于制作材(cai)料(liao)(liao)(liao)上。密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)材(cai)料(liao)(liao)(liao)主要使用(yong)橡(xiang)膠和(he)合(he)成樹脂。由于各(ge)種材(cai)料(liao)(liao)(liao)性能特點不同(tong)(tong)(tong)(tong)(tong)，性能特點不同(tong)(tong)(tong)(tong)(tong)，用(yong)途也就(jiu)有(you)所(suo)不同(tong)(tong)(tong)(tong)(tong)。選用(yong)時需根據不同(tong)(tong)(tong)(tong)(tong)的(de)(de)(de)使用(yong)條(tiao)件和(he)不同(tong)(tong)(tong)(tong)(tong)的(de)(de)(de)使用(yong)條(tiao)件作出(chu)合(he)適(shi)的(de)(de)(de)選擇。另(ling)外，某一(yi)材(cai)質的(de)(de)(de)密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)對被(bei)密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)的(de)(de)(de)某一(yi)工作介(jie)質(如礦(kuang)物油(you)等(deng))表現較好的(de)(de)(de)密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)性能，而對另(ling)一(yi)介(jie)質表現極(ji)差，這就(jiu)是密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)材(cai)料(liao)(liao)(liao)與液壓油(you)的(de)(de)(de)相容性。還有(you)，各(ge)種不同(tong)(tong)(tong)(tong)(tong)的(de)(de)(de)密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)材(cai)料(liao)(liao)(liao)對你(ni)不同(tong)(tong)(tong)(tong)(tong)的(de)(de)(de)工作條(tiao)件表現出(chu)不同(tong)(tong)(tong)(tong)(tong)的(de)(de)(de)性能。有(you)些(xie)(xie)(xie)(xie)耐熱(re)(re)，有(you)些(xie)(xie)(xie)(xie)不耐熱(re)(re);有(you)些(xie)(xie)(xie)(xie)耐酸，有(you)些(xie)(xie)(xie)(xie)耐堿，有(you)些(xie)(xie)(xie)(xie)耐水，有(you)些(xie)(xie)(xie)(xie)耐油(you);有(you)些(xie)(xie)(xie)(xie)抗熱(re)(re)，有(you)些(xie)(xie)(xie)(xie)耐低溫，有(you)些(xie)(xie)(xie)(xie)耐高溫，等(deng)等(deng)。這些(xie)(xie)(xie)(xie)因素在(zai)考慮密(mi)(mi)(mi)(mi)封(feng)(feng)(feng)(feng)件材(cai)料(liao)(liao)(liao)的(de)(de)(de)時候需注(zhu)意。