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。渣漿泵用武鄉機械密封的工作原理要求武鄉機械密封內部無任何雜質，在組裝武鄉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武鄉機械密封嚴重漏泄。必要時可以制(zhi)作(zuo)工裝在(zai)組裝前水壓試驗，檢查動(dong)靜環座是否存在(zai)影響密封(feng)的缺(que)陷(xian)。

　　渣漿武鄉泵用武鄉機械密封由于密封面變形所引起的，而且武鄉機械密封面泄漏的概率是很高的。如果泵在啟動時就發生武鄉泵用武鄉機械密封泄漏，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武鄉機械密封的變(bian)形情(qing)(qing)況。如果發生變(bian)形，用平晶檢查密(mi)封(feng)面(mian)的干(gan)涉帶的變(bian)化情(qing)(qing)況，密(mi)封(feng)面(mian)變(bian)形存(cun)在于(yu)動環和靜環之間。

　　壓缸(gang)體動(dong)(dong)(dong)(dong)(dong)態密(mi)(mi)(mi)(mi)封(feng)系統采用的(de)(de)是主密(mi)(mi)(mi)(mi)封(feng)設計，一般(ban)都用U型密(mi)(mi)(mi)(mi)封(feng)圈(quan)。液壓缸(gang)體的(de)(de)往(wang)復(fu)式動(dong)(dong)(dong)(dong)(dong)態密(mi)(mi)(mi)(mi)封(feng)系統的(de)(de)設計，開始使用了更加復(fu)雜的(de)(de)U型圈(quan)和(he)同軸密(mi)(mi)(mi)(mi)封(feng)組件(jian)的(de)(de)復(fu)合式設計。密(mi)(mi)(mi)(mi)封(feng)的(de)(de)靜(jing)環(huan)(huan)通(tong)(tong)(tong)常固定在殼體上，動(dong)(dong)(dong)(dong)(dong)環(huan)(huan)通(tong)(tong)(tong)過(guo)彈簧(huang)、彈簧(huang)座與(yu)(yu)軸一同旋(xuan)轉。靜(jing)環(huan)(huan)與(yu)(yu)殼體、動(dong)(dong)(dong)(dong)(dong)環(huan)(huan)與(yu)(yu)軸形成的(de)(de)間隙(xi)用成型填料密(mi)(mi)(mi)(mi)封(feng)。在動(dong)(dong)(dong)(dong)(dong)環(huan)(huan)和(he)靜(jing)環(huan)(huan)接(jie)觸的(de)(de)端面(mian)(mian)形成相對滑動(dong)(dong)(dong)(dong)(dong)面(mian)(mian)，即(ji)動(dong)(dong)(dong)(dong)(dong)密(mi)(mi)(mi)(mi)封(feng)面(mian)(mian)。為保證密(mi)(mi)(mi)(mi)封(feng)良好，動(dong)(dong)(dong)(dong)(dong)密(mi)(mi)(mi)(mi)封(feng)面(mian)(mian)應十分(fen)平直和(he)光潔。彈簧(huang)力(li)和(he)被密(mi)(mi)(mi)(mi)封(feng)的(de)(de)流(liu)體壓力(li)使動(dong)(dong)(dong)(dong)(dong)環(huan)(huan)貼緊靜(jing)環(huan)(huan)。因動(dong)(dong)(dong)(dong)(dong)環(huan)(huan)與(yu)(yu)軸通(tong)(tong)(tong)過(guo)彈簧(huang)連接(jie)，動(dong)(dong)(dong)(dong)(dong)環(huan)(huan)和(he)靜(jing)環(huan)(huan)間貼合性受(shou)軸的(de)(de)振動(dong)(dong)(dong)(dong)(dong)和(he)擺動(dong)(dong)(dong)(dong)(dong)影響較小。靜(jing)環(huan)(huan)一般(ban)常用潤滑性好的(de)(de)軟質(zhi)(zhi)材料如石(shi)墨、填充聚四氟(fu)乙烯等(deng)，動(dong)(dong)(dong)(dong)(dong)環(huan)(huan)多用硬質(zhi)(zhi)合金(jin)、陶瓷等(deng)材料制造。