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。渣漿泵用汶上機械密封的工作原理要求汶上機械密封內部無任何雜質，在組裝汶上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汶上機械密封嚴重漏泄(xie)。必(bi)要時可以制作工裝(zhuang)在(zai)組裝(zhuang)前水壓試驗，檢查動(dong)靜環座是否存在(zai)影響密(mi)封的缺(que)陷。

　　渣漿汶上泵用汶上機械密封由于密封面變形所引起的，而且汶上機械密封面泄漏的概率是很高的。如果泵在啟動時就發生汶上泵用汶上機械密封泄漏，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汶上機械密封的(de)變(bian)形情(qing)況。如果發(fa)生變(bian)形，用平晶檢查密封(feng)面(mian)的(de)干涉帶的(de)變(bian)化情(qing)況，密封(feng)面(mian)變(bian)形存在于動環(huan)和靜環(huan)之間。

　　壓(ya)(ya)缸體(ti)動(dong)(dong)(dong)(dong)態(tai)(tai)密封(feng)(feng)(feng)(feng)(feng)(feng)系統采用的是主密封(feng)(feng)(feng)(feng)(feng)(feng)設(she)計，一(yi)(yi)般(ban)都用U型(xing)密封(feng)(feng)(feng)(feng)(feng)(feng)圈。液壓(ya)(ya)缸體(ti)的往(wang)復(fu)式動(dong)(dong)(dong)(dong)態(tai)(tai)密封(feng)(feng)(feng)(feng)(feng)(feng)系統的設(she)計，開(kai)始使用了更加(jia)復(fu)雜的U型(xing)圈和(he)(he)同軸密封(feng)(feng)(feng)(feng)(feng)(feng)組(zu)件的復(fu)合(he)式設(she)計。密封(feng)(feng)(feng)(feng)(feng)(feng)的靜(jing)(jing)環(huan)通常(chang)(chang)固定在殼體(ti)上，動(dong)(dong)(dong)(dong)環(huan)通過(guo)(guo)彈(dan)簧(huang)(huang)、彈(dan)簧(huang)(huang)座(zuo)與軸一(yi)(yi)同旋轉。靜(jing)(jing)環(huan)與殼體(ti)、動(dong)(dong)(dong)(dong)環(huan)與軸形成的間隙用成型(xing)填料密封(feng)(feng)(feng)(feng)(feng)(feng)。在動(dong)(dong)(dong)(dong)環(huan)和(he)(he)靜(jing)(jing)環(huan)接觸的端面(mian)(mian)形成相對滑動(dong)(dong)(dong)(dong)面(mian)(mian)，即動(dong)(dong)(dong)(dong)密封(feng)(feng)(feng)(feng)(feng)(feng)面(mian)(mian)。為(wei)保(bao)證密封(feng)(feng)(feng)(feng)(feng)(feng)良好，動(dong)(dong)(dong)(dong)密封(feng)(feng)(feng)(feng)(feng)(feng)面(mian)(mian)應十分平直和(he)(he)光潔。彈(dan)簧(huang)(huang)力和(he)(he)被密封(feng)(feng)(feng)(feng)(feng)(feng)的流體(ti)壓(ya)(ya)力使動(dong)(dong)(dong)(dong)環(huan)貼(tie)緊靜(jing)(jing)環(huan)。因動(dong)(dong)(dong)(dong)環(huan)與軸通過(guo)(guo)彈(dan)簧(huang)(huang)連接，動(dong)(dong)(dong)(dong)環(huan)和(he)(he)靜(jing)(jing)環(huan)間貼(tie)合(he)性(xing)受(shou)軸的振動(dong)(dong)(dong)(dong)和(he)(he)擺動(dong)(dong)(dong)(dong)影響(xiang)較小。靜(jing)(jing)環(huan)一(yi)(yi)般(ban)常(chang)(chang)用潤滑性(xing)好的軟(ruan)質材料如(ru)石墨、填充聚四氟(fu)乙烯等(deng)，動(dong)(dong)(dong)(dong)環(huan)多用硬質合(he)金(jin)、陶瓷(ci)等(deng)材料制造。