填(tian)(tian)(tian)(tian)料(liao)(liao)改集式密封是指通(tong)過預(yu)緊(jin)或介(jie)質壓力的(de)自(zi)緊(jin)作用(yong)使(shi)填(tian)(tian)(tian)(tian)料(liao)(liao)與(yu)轉動(dong)(dong)件(jian)及固定(ding)件(jian)之(zhi)間產生壓緊(jin)力的(de)動(dong)(dong)密封裝置。又稱(cheng)“填(tian)(tian)(tian)(tian)料(liao)(liao)函密封”。結構(gou)形式較多，主要由填(tian)(tian)(tian)(tian)料(liao)(liao)、填(tian)(tian)(tian)(tian)料(liao)(liao)箱(xiang)和(he)填(tian)(tian)(tian)(tian)料(liao)(liao)固定(ding)件(jian)組(zu)成(cheng)。常用(yong)的(de)填(tian)(tian)(tian)(tian)料(liao)(liao)材料(liao)(liao)有石(shi)棉織物、碳纖維、橡膠(jiao)、柔性(xing)石(shi)墨和(he)工(gong)程塑料(liao)(liao)等，預(yu)制成(cheng)環(huan)(huan)狀(zhuang)或條狀(zhuang)（有的(de)需預(yu)先浸漬潤滑性(xing)好的(de)填(tian)(tian)(tian)(tian)充物），并采用(yong)多環(huan)(huan)或螺旋(xuan)狀(zhuang)多層(ceng)結構(gou)。填(tian)(tian)(tian)(tian)料(liao)(liao)箱(xiang)用(yong)以安置填(tian)(tian)(tian)(tian)料(liao)(liao)。填(tian)(tian)(tian)(tian)料(liao)(liao)固定(ding)件(jian)包括壓蓋、螺栓和(he)彈簧(huang)等，用(yong)以使(shi)填(tian)(tian)(tian)(tian)料(liao)(liao)預(yu)緊(jin)，工(gong)作時阻(zu)止介(jie)質外漏，彈簧(huang)可(ke)起補(bu)償(chang)作用(yong)。

　　填料(liao)(liao)(liao)(liao)裝入填料(liao)(liao)(liao)(liao)腔以后，經壓(ya)(ya)蓋螺絲對(dui)它作軸(zhou)向壓(ya)(ya)縮(suo)，當軸(zhou)與填料(liao)(liao)(liao)(liao)有相對(dui)運(yun)動時，由于(yu)填料(liao)(liao)(liao)(liao)的(de)(de)塑性，使它產生徑向力，并與軸(zhou)緊密(mi)接(jie)(jie)(jie)觸(chu)(chu)(chu)。與此同(tong)時，填料(liao)(liao)(liao)(liao)中浸漬的(de)(de)潤(run)(run)(run)滑劑被擠(ji)出(chu)，在(zai)接(jie)(jie)(jie)觸(chu)(chu)(chu)面(mian)之間(jian)(jian)形成(cheng)(cheng)油(you)膜。由于(yu)接(jie)(jie)(jie)觸(chu)(chu)(chu)狀(zhuang)態并不(bu)是(shi)特別均勻(yun)的(de)(de)，接(jie)(jie)(jie)觸(chu)(chu)(chu)部(bu)位(wei)(wei)便出(chu)現(xian)(xian)(xian)“邊界潤(run)(run)(run)滑”狀(zhuang)態，稱為“軸(zhou)承效(xiao)(xiao)應(ying)(ying)”；而未接(jie)(jie)(jie)觸(chu)(chu)(chu)的(de)(de)凹部(bu)形成(cheng)(cheng)小油(you)槽，有較厚的(de)(de)油(you)膜，接(jie)(jie)(jie)觸(chu)(chu)(chu)部(bu)位(wei)(wei)與非(fei)接(jie)(jie)(jie)觸(chu)(chu)(chu)部(bu)位(wei)(wei)組成(cheng)(cheng)一道不(bu)規則(ze)的(de)(de)迷宮，起阻止(zhi)液流泄漏(lou)的(de)(de)作用，此稱“迷宮效(xiao)(xiao)應(ying)(ying)”。這就是(shi)填料(liao)(liao)(liao)(liao)密(mi)封的(de)(de)機理。顯然，良好的(de)(de)密(mi)封在(zai)于(yu)維持“軸(zhou)承效(xiao)(xiao)應(ying)(ying)”和“迷宮效(xiao)(xiao)應(ying)(ying)”。也就是(shi)說，要保持良好的(de)(de)潤(run)(run)(run)滑和適當的(de)(de)壓(ya)(ya)緊。若潤(run)(run)(run)滑不(bu)良，或壓(ya)(ya)得過緊都會使油(you)膜中斷，造成(cheng)(cheng)填料(liao)(liao)(liao)(liao)與軸(zhou)之間(jian)(jian)出(chu)現(xian)(xian)(xian)干摩擦，最后導致(zhi)燒軸(zhou)和出(chu)現(xian)(xian)(xian)嚴重磨損(sun)。

　　為此(ci)，需要(yao)經(jing)常(chang)對填(tian)(tian)料(liao)(liao)的(de)(de)壓緊(jin)程度進行調(diao)整(zheng)，以便填(tian)(tian)料(liao)(liao)中的(de)(de)潤滑(hua)劑(ji)在運(yun)行一段時(shi)間流失之后，再擠出一些潤滑(hua)劑(ji)，同時(shi)補償填(tian)(tian)料(liao)(liao)因體積變化所(suo)(suo)造成的(de)(de)壓緊(jin)力松弛(chi)。顯然(ran)，這樣經(jing)常(chang)擠壓填(tian)(tian)料(liao)(liao)，最終(zhong)將使浸漬劑(ji)枯(ku)竭，所(suo)(suo)以定期更(geng)換填(tian)(tian)料(liao)(liao)是必(bi)要(yao)的(de)(de)。此(ci)外(wai)，為了維(wei)持液膜和帶走摩擦熱，有(you)意(yi)讓(rang)填(tian)(tian)料(liao)(liao)處(chu)有(you)少量泄漏也是必(bi)要(yao)的(de)(de)。