填(tian)(tian)(tian)料(liao)(liao)改集式(shi)密封(feng)是指通(tong)過預緊(jin)或(huo)(huo)介質壓力的(de)(de)自緊(jin)作(zuo)用(yong)(yong)使填(tian)(tian)(tian)料(liao)(liao)與轉動(dong)件(jian)(jian)及固定(ding)(ding)(ding)件(jian)(jian)之間產生(sheng)壓緊(jin)力的(de)(de)動(dong)密封(feng)裝置(zhi)。又稱“填(tian)(tian)(tian)料(liao)(liao)函密封(feng)”。結構(gou)形(xing)式(shi)較多(duo)(duo)，主要由填(tian)(tian)(tian)料(liao)(liao)、填(tian)(tian)(tian)料(liao)(liao)箱和(he)填(tian)(tian)(tian)料(liao)(liao)固定(ding)(ding)(ding)件(jian)(jian)組成(cheng)。常用(yong)(yong)的(de)(de)填(tian)(tian)(tian)料(liao)(liao)材(cai)料(liao)(liao)有石棉織物、碳纖(xian)維、橡膠(jiao)、柔性石墨和(he)工程塑料(liao)(liao)等，預制成(cheng)環狀(zhuang)或(huo)(huo)條狀(zhuang)（有的(de)(de)需預先浸(jin)漬潤(run)滑性好的(de)(de)填(tian)(tian)(tian)充物），并采用(yong)(yong)多(duo)(duo)環或(huo)(huo)螺旋(xuan)狀(zhuang)多(duo)(duo)層結構(gou)。填(tian)(tian)(tian)料(liao)(liao)箱用(yong)(yong)以安置(zhi)填(tian)(tian)(tian)料(liao)(liao)。填(tian)(tian)(tian)料(liao)(liao)固定(ding)(ding)(ding)件(jian)(jian)包括壓蓋、螺栓和(he)彈簧等，用(yong)(yong)以使填(tian)(tian)(tian)料(liao)(liao)預緊(jin)，工作(zuo)時(shi)阻(zu)止介質外(wai)漏(lou)，彈簧可(ke)起補(bu)償(chang)作(zuo)用(yong)(yong)。

　　填(tian)(tian)(tian)(tian)料(liao)(liao)裝入填(tian)(tian)(tian)(tian)料(liao)(liao)腔以(yi)后，經壓(ya)蓋螺絲對(dui)它作(zuo)軸(zhou)(zhou)(zhou)向(xiang)壓(ya)縮，當軸(zhou)(zhou)(zhou)與(yu)(yu)填(tian)(tian)(tian)(tian)料(liao)(liao)有相對(dui)運動(dong)時(shi)(shi)，由于(yu)(yu)填(tian)(tian)(tian)(tian)料(liao)(liao)的(de)塑性，使(shi)它產生徑向(xiang)力(li)，并與(yu)(yu)軸(zhou)(zhou)(zhou)緊(jin)密接(jie)(jie)觸(chu)(chu)(chu)(chu)。與(yu)(yu)此同時(shi)(shi)，填(tian)(tian)(tian)(tian)料(liao)(liao)中(zhong)浸漬的(de)潤滑(hua)劑被(bei)擠出(chu)，在接(jie)(jie)觸(chu)(chu)(chu)(chu)面之(zhi)間形(xing)成(cheng)油(you)(you)膜(mo)。由于(yu)(yu)接(jie)(jie)觸(chu)(chu)(chu)(chu)狀(zhuang)(zhuang)態并不是特別均(jun)勻的(de)，接(jie)(jie)觸(chu)(chu)(chu)(chu)部(bu)(bu)位(wei)(wei)便(bian)出(chu)現“邊界潤滑(hua)”狀(zhuang)(zhuang)態，稱為“軸(zhou)(zhou)(zhou)承效(xiao)應(ying)”；而未接(jie)(jie)觸(chu)(chu)(chu)(chu)的(de)凹部(bu)(bu)形(xing)成(cheng)小油(you)(you)槽，有較厚的(de)油(you)(you)膜(mo)，接(jie)(jie)觸(chu)(chu)(chu)(chu)部(bu)(bu)位(wei)(wei)與(yu)(yu)非接(jie)(jie)觸(chu)(chu)(chu)(chu)部(bu)(bu)位(wei)(wei)組(zu)成(cheng)一道(dao)不規則的(de)迷宮(gong)(gong)，起阻止液(ye)流泄(xie)漏(lou)的(de)作(zuo)用，此稱“迷宮(gong)(gong)效(xiao)應(ying)”。這就是填(tian)(tian)(tian)(tian)料(liao)(liao)密封的(de)機理。顯(xian)然(ran)，良(liang)好的(de)密封在于(yu)(yu)維持“軸(zhou)(zhou)(zhou)承效(xiao)應(ying)”和“迷宮(gong)(gong)效(xiao)應(ying)”。也就是說，要保(bao)持良(liang)好的(de)潤滑(hua)和適當的(de)壓(ya)緊(jin)。若潤滑(hua)不良(liang)，或壓(ya)得(de)過緊(jin)都會使(shi)油(you)(you)膜(mo)中(zhong)斷，造成(cheng)填(tian)(tian)(tian)(tian)料(liao)(liao)與(yu)(yu)軸(zhou)(zhou)(zhou)之(zhi)間出(chu)現干(gan)摩擦，最后導致燒軸(zhou)(zhou)(zhou)和出(chu)現嚴重磨損(sun)。

　　為(wei)此，需要(yao)(yao)經(jing)常對填(tian)料(liao)(liao)(liao)的(de)壓(ya)(ya)緊程度進行調整，以便填(tian)料(liao)(liao)(liao)中的(de)潤(run)滑劑在運行一(yi)(yi)段時間流失之后，再擠出一(yi)(yi)些潤(run)滑劑，同時補償填(tian)料(liao)(liao)(liao)因體積變化所(suo)(suo)造(zao)成的(de)壓(ya)(ya)緊力松弛。顯然，這樣經(jing)常擠壓(ya)(ya)填(tian)料(liao)(liao)(liao)，最(zui)終將(jiang)使浸(jin)漬(zi)劑枯(ku)竭，所(suo)(suo)以定期更換填(tian)料(liao)(liao)(liao)是必要(yao)(yao)的(de)。此外(wai)，為(wei)了維(wei)持液膜和(he)帶(dai)走(zou)摩擦熱，有(you)意讓填(tian)料(liao)(liao)(liao)處(chu)有(you)少量泄漏也是必要(yao)(yao)的(de)。