當陽機械密封包括壓力控制、溫度控制、流體替換(堵塞)和雜質去除系統。在當陽機械密封系(xi)統(tong)(tong)(tong)中，上述系(xi)統(tong)(tong)(tong)并不同時包括在(zai)內。密封(feng)(feng)(feng)系(xi)統(tong)(tong)(tong)的選(xuan)擇主(zhu)要取決于(yu)主(zhu)密封(feng)(feng)(feng)件的應用(yong)(yong)(yong)范圍。例如(ru)(ru)，如(ru)(ru)果(guo)主(zhu)密封(feng)(feng)(feng)用(yong)(yong)(yong)于(yu)高(gao)溫液體(ti)(ti)(ti)，密封(feng)(feng)(feng)系(xi)統(tong)(tong)(tong)應確(que)保降(jiang)低(di)(di)主(zhu)密封(feng)(feng)(feng)的環境溫度(du)，即采(cai)用(yong)(yong)(yong)溫度(du)控(kong)制系(xi)統(tong)(tong)(tong)。如(ru)(ru)果(guo)主(zhu)密封(feng)(feng)(feng)用(yong)(yong)(yong)于(yu)固體(ti)(ti)(ti)雜質(zhi)(zhi)含量高(gao)的工作介質(zhi)(zhi)，密封(feng)(feng)(feng)系(xi)統(tong)(tong)(tong)應確(que)保在(zai)主(zhu)密封(feng)(feng)(feng)前降(jiang)低(di)(di)固體(ti)(ti)(ti)雜質(zhi)(zhi)含量，即采(cai)用(yong)(yong)(yong)除雜系(xi)統(tong)(tong)(tong)。在(zai)腐(fu)蝕性介質(zhi)(zhi)中，密封(feng)(feng)(feng)系(xi)統(tong)(tong)(tong)必須確(que)保主(zhu)密封(feng)(feng)(feng)降(jiang)低(di)(di)腐(fu)蝕速率或消除腐(fu)蝕，即使用(yong)(yong)(yong)流(liu)體(ti)(ti)(ti)而不是堵(du)塞流(liu)體(ti)(ti)(ti)系(xi)統(tong)(tong)(tong)；在(zai)高(gao)壓密封(feng)(feng)(feng)裝(zhuang)置中，輔助(zhu)系(xi)統(tong)(tong)(tong)應確(que)保多級降(jiang)壓和其他措施(shi)，即壓力控(kong)制系(xi)統(tong)(tong)(tong)。

　　當陽機械密封的三個(ge)主要功能(neng)如下：

　　1、沖洗功能，沖洗是當陽機械密封基本的功能，它直接將液體注入單面密封或雙面密封的高壓側。一般的當陽機械密封應該沖洗，特別是對(dui)于輕烴泵，沖洗時達到隔離介質、冷卻和改善潤滑(hua)的(de)目的(de)。隔離介質的(de)目的(de)可以(yi)通過(guo)將與介質相(xiang)容的(de)液體引入密封腔進行外(wai)部循環沖洗來實現。

　　2、除雜和過濾功能，密封流體中的微細固體粒子、污垢等雜質對當陽機械密封造(zao)成的危(wei)害非常嚴重(zhong)，可(ke)(ke)能(neng)(neng)導(dao)致密(mi)(mi)封(feng)端面的磨損，也可(ke)(ke)能(neng)(neng)堵(du)塞寒冷密(mi)(mi)封(feng)系(xi)統的管線。密(mi)(mi)封(feng)性系(xi)統軟件(jian)具有去除(chu)殘渣(zha)、保持液(ye)體(ti)清潔(jie)的作用(yong)。當殘渣(zha)的相對密(mi)(mi)度(du)(du)小于液(ye)體(ti)媒質相對密(mi)(mi)度(du)(du)時(shi)，能(neng)(neng)用(yong)過濾裝置去除(chu)殘渣(zha)；而當殘渣(zha)的相對密(mi)(mi)度(du)(du)超(chao)過液(ye)體(ti)媒質相對密(mi)(mi)度(du)(du)時(shi)，可(ke)(ke)選(xuan)用(yong)旋液(ye)分離設備或網式過濾器去除(chu)殘渣(zha)。

　　3、流體替代功能，含有固體顆粒的氣相介質和液相介質的直接密封難度很大，它們溫、毒、貴、易蒸發、易結晶。借助當陽機械密封可以用雙端當陽機械密封代替密(mi)封(feng)介質，將(jiang)難以直接(jie)密(mi)封(feng)的(de)(de)介質轉化(hua)為密(mi)封(feng)潤滑(hua)性能好、清(qing)潔的(de)(de)密(mi)封(feng)液體介質。