反壓狀態是不良的工作狀態，介質中的顆粒、雜質很容易進入密封面，使密封失效。磨軸的主要件為橡膠波紋管，且由于上端密封面處于不良潤滑狀態，動靜環之間的摩擦力矩大于橡膠波紋管與軸之間的傳遞轉矩，從而發生相對轉動。動、靜環輔助密封由于受到污水中的弱酸、弱堿的腐蝕，橡膠件已無彈性。渣漿洞頭泵用洞頭機械密封的工作原理要求洞頭機械密封內部無任何雜質，在組裝洞頭機械密封前要徹底清掃動環、靜環、軸套等部件，檢查動靜環表面是否存在劃痕、裂紋等缺陷，這些缺陷存在會造成洞頭機械密封嚴(yan)重漏泄。必要時可以制(zhi)作工裝在組(zu)裝前(qian)水壓(ya)試驗(yan)，檢查動靜環(huan)座是否存(cun)在影響密封的缺陷。

　　渣漿洞頭泵用洞頭機械密封由于密封面變形所引起的，而且洞頭機械密封面泄漏的概率是很高的。如果泵在啟動時就發生洞頭泵用洞頭機械密封泄漏，而拆查密封面時看不見有損壞的地方，這時就應該用平晶檢查洞頭機械密封的變形情況(kuang)。如果發生變形，用平(ping)晶(jing)檢查密(mi)封面的干(gan)涉帶的變化情況(kuang)，密(mi)封面變形存在于(yu)動環和(he)靜環之間。

　　壓缸體(ti)動(dong)(dong)(dong)(dong)(dong)態(tai)密(mi)(mi)(mi)封(feng)系(xi)統(tong)采用(yong)(yong)(yong)(yong)的(de)(de)(de)(de)是(shi)主密(mi)(mi)(mi)封(feng)設(she)計，一(yi)般都用(yong)(yong)(yong)(yong)U型(xing)密(mi)(mi)(mi)封(feng)圈(quan)。液壓缸體(ti)的(de)(de)(de)(de)往復(fu)(fu)式(shi)(shi)動(dong)(dong)(dong)(dong)(dong)態(tai)密(mi)(mi)(mi)封(feng)系(xi)統(tong)的(de)(de)(de)(de)設(she)計，開始使用(yong)(yong)(yong)(yong)了更加復(fu)(fu)雜的(de)(de)(de)(de)U型(xing)圈(quan)和(he)同軸(zhou)密(mi)(mi)(mi)封(feng)組件的(de)(de)(de)(de)復(fu)(fu)合(he)式(shi)(shi)設(she)計。密(mi)(mi)(mi)封(feng)的(de)(de)(de)(de)靜環(huan)通(tong)常(chang)(chang)固定在殼體(ti)上(shang)，動(dong)(dong)(dong)(dong)(dong)環(huan)通(tong)過彈(dan)簧、彈(dan)簧座與(yu)軸(zhou)一(yi)同旋轉。靜環(huan)與(yu)殼體(ti)、動(dong)(dong)(dong)(dong)(dong)環(huan)與(yu)軸(zhou)形成的(de)(de)(de)(de)間(jian)(jian)隙用(yong)(yong)(yong)(yong)成型(xing)填(tian)料(liao)密(mi)(mi)(mi)封(feng)。在動(dong)(dong)(dong)(dong)(dong)環(huan)和(he)靜環(huan)接觸(chu)的(de)(de)(de)(de)端面(mian)形成相對滑動(dong)(dong)(dong)(dong)(dong)面(mian)，即動(dong)(dong)(dong)(dong)(dong)密(mi)(mi)(mi)封(feng)面(mian)。為保證密(mi)(mi)(mi)封(feng)良好(hao)，動(dong)(dong)(dong)(dong)(dong)密(mi)(mi)(mi)封(feng)面(mian)應十分平直和(he)光潔。彈(dan)簧力(li)和(he)被密(mi)(mi)(mi)封(feng)的(de)(de)(de)(de)流體(ti)壓力(li)使動(dong)(dong)(dong)(dong)(dong)環(huan)貼緊靜環(huan)。因動(dong)(dong)(dong)(dong)(dong)環(huan)與(yu)軸(zhou)通(tong)過彈(dan)簧連接，動(dong)(dong)(dong)(dong)(dong)環(huan)和(he)靜環(huan)間(jian)(jian)貼合(he)性(xing)受(shou)軸(zhou)的(de)(de)(de)(de)振動(dong)(dong)(dong)(dong)(dong)和(he)擺動(dong)(dong)(dong)(dong)(dong)影(ying)響(xiang)較小。靜環(huan)一(yi)般常(chang)(chang)用(yong)(yong)(yong)(yong)潤滑性(xing)好(hao)的(de)(de)(de)(de)軟質(zhi)材料(liao)如(ru)石墨(mo)、填(tian)充聚四氟(fu)乙烯等，動(dong)(dong)(dong)(dong)(dong)環(huan)多用(yong)(yong)(yong)(yong)硬(ying)質(zhi)合(he)金、陶瓷等材料(liao)制造。