填(tian)(tian)(tian)(tian)(tian)料改集式密(mi)封(feng)是(shi)指通過預緊或介質壓力的(de)自緊作(zuo)用使填(tian)(tian)(tian)(tian)(tian)料與轉動件(jian)(jian)(jian)及固(gu)定(ding)件(jian)(jian)(jian)之間(jian)產生壓緊力的(de)動密(mi)封(feng)裝置。又(you)稱“填(tian)(tian)(tian)(tian)(tian)料函密(mi)封(feng)”。結構形式較(jiao)多(duo)，主要(yao)由(you)填(tian)(tian)(tian)(tian)(tian)料、填(tian)(tian)(tian)(tian)(tian)料箱和(he)(he)填(tian)(tian)(tian)(tian)(tian)料固(gu)定(ding)件(jian)(jian)(jian)組成。常用的(de)填(tian)(tian)(tian)(tian)(tian)料材料有石棉(mian)織物、碳(tan)纖維、橡(xiang)膠、柔性石墨(mo)和(he)(he)工(gong)程塑料等，預制成環狀(zhuang)或條狀(zhuang)（有的(de)需預先(xian)浸(jin)漬潤滑性好的(de)填(tian)(tian)(tian)(tian)(tian)充物），并采用多(duo)環或螺旋狀(zhuang)多(duo)層結構。填(tian)(tian)(tian)(tian)(tian)料箱用以(yi)安置填(tian)(tian)(tian)(tian)(tian)料。填(tian)(tian)(tian)(tian)(tian)料固(gu)定(ding)件(jian)(jian)(jian)包括壓蓋、螺栓和(he)(he)彈(dan)簧等，用以(yi)使填(tian)(tian)(tian)(tian)(tian)料預緊，工(gong)作(zuo)時阻止介質外漏(lou)，彈(dan)簧可(ke)起補償作(zuo)用。

　　填(tian)料(liao)裝入(ru)填(tian)料(liao)腔以(yi)后，經壓蓋螺絲對(dui)它(ta)作軸(zhou)向(xiang)壓縮(suo)，當軸(zhou)與(yu)(yu)(yu)填(tian)料(liao)有(you)相對(dui)運動(dong)時，由于填(tian)料(liao)的(de)(de)(de)(de)塑性，使它(ta)產生徑向(xiang)力(li)，并與(yu)(yu)(yu)軸(zhou)緊(jin)密接(jie)(jie)觸。與(yu)(yu)(yu)此同時，填(tian)料(liao)中浸漬的(de)(de)(de)(de)潤滑(hua)(hua)(hua)劑被擠出(chu)(chu)(chu)，在接(jie)(jie)觸面之(zhi)間(jian)(jian)形(xing)成(cheng)油(you)(you)(you)膜。由于接(jie)(jie)觸狀(zhuang)態(tai)并不(bu)是(shi)(shi)特別均(jun)勻的(de)(de)(de)(de)，接(jie)(jie)觸部(bu)位便出(chu)(chu)(chu)現“邊界潤滑(hua)(hua)(hua)”狀(zhuang)態(tai)，稱為“軸(zhou)承(cheng)效應(ying)”；而未接(jie)(jie)觸的(de)(de)(de)(de)凹部(bu)形(xing)成(cheng)小油(you)(you)(you)槽，有(you)較厚的(de)(de)(de)(de)油(you)(you)(you)膜，接(jie)(jie)觸部(bu)位與(yu)(yu)(yu)非(fei)接(jie)(jie)觸部(bu)位組(zu)成(cheng)一道(dao)不(bu)規則(ze)的(de)(de)(de)(de)迷(mi)宮(gong)，起(qi)阻止液流泄漏的(de)(de)(de)(de)作用，此稱“迷(mi)宮(gong)效應(ying)”。這就(jiu)是(shi)(shi)填(tian)料(liao)密封的(de)(de)(de)(de)機理。顯然，良好的(de)(de)(de)(de)密封在于維持“軸(zhou)承(cheng)效應(ying)”和(he)“迷(mi)宮(gong)效應(ying)”。也(ye)就(jiu)是(shi)(shi)說，要保持良好的(de)(de)(de)(de)潤滑(hua)(hua)(hua)和(he)適當的(de)(de)(de)(de)壓緊(jin)。若(ruo)潤滑(hua)(hua)(hua)不(bu)良，或壓得(de)過緊(jin)都會使油(you)(you)(you)膜中斷(duan)，造成(cheng)填(tian)料(liao)與(yu)(yu)(yu)軸(zhou)之(zhi)間(jian)(jian)出(chu)(chu)(chu)現干摩(mo)擦(ca)，最后導致燒軸(zhou)和(he)出(chu)(chu)(chu)現嚴重磨損。

　　為此，需要(yao)(yao)經常對填(tian)(tian)(tian)料(liao)的(de)壓緊程度進(jin)行調整，以(yi)便填(tian)(tian)(tian)料(liao)中的(de)潤滑劑(ji)(ji)在運行一段時(shi)間流失之后，再擠出一些潤滑劑(ji)(ji)，同時(shi)補償填(tian)(tian)(tian)料(liao)因(yin)體積變化所造成的(de)壓緊力(li)松弛。顯(xian)然，這樣經常擠壓填(tian)(tian)(tian)料(liao)，最終將使浸漬劑(ji)(ji)枯(ku)竭，所以(yi)定(ding)期更換(huan)填(tian)(tian)(tian)料(liao)是(shi)必要(yao)(yao)的(de)。此外，為了維持液(ye)膜和帶走摩擦熱，有意讓填(tian)(tian)(tian)料(liao)處(chu)有少量泄漏也是(shi)必要(yao)(yao)的(de)。