顧名思義，封頭就是容器的兩端的端蓋。所以，封頭一般都是用于與各種筒體的配對后，組成壓力容器。

 封頭是常(chang)壓及承壓容器中不(bu)可(ke)或(huo)缺(que)的零(ling)部件，廣(guang)泛用于石油、電子(zi)、供(gong)暖(nuan)、化工(gong)(gong)、醫藥、污水處理、輕紡、食品、機(ji)械、建筑、核電、航空航天、壓力(li)容器、軍工(gong)(gong)等行業。

封頭(tou)是壓(ya)(ya)力容(rong)器(qi)的(de)重要受壓(ya)(ya)元件之一，它不但直接影響容(rong)器(qi)的(de)制造質量和成(cheng)本，而且還影響生產裝(zhuang)置的(de)安(an)全和長(chang)期運行。常(chang)用的(de)裝(zhuang)置有反應壓(ya)(ya)力容(rong)器(qi)，熱交換壓(ya)(ya)力容(rong)器(qi)，分(fen)離壓(ya)(ya)力容(rong)器(qi)，儲存壓(ya)(ya)力容(rong)器(qi)等(deng)等(deng)。

 封(feng)(feng)(feng)頭(tou)(tou)(tou)(tou)的種類繁多，按(an)用途可(ke)分為(wei)承壓(ya)(ya)封(feng)(feng)(feng)頭(tou)(tou)(tou)(tou)和常壓(ya)(ya)封(feng)(feng)(feng)頭(tou)(tou)(tou)(tou)，按(an)形(xing)(xing)狀可(ke)分為(wei)橢圓封(feng)(feng)(feng)頭(tou)(tou)(tou)(tou)、蝶形(xing)(xing)封(feng)(feng)(feng)頭(tou)(tou)(tou)(tou)、球(qiu)冠形(xing)(xing)封(feng)(feng)(feng)頭(tou)(tou)(tou)(tou)、半球(qiu)形(xing)(xing)封(feng)(feng)(feng)頭(tou)(tou)(tou)(tou)、弓形(xing)(xing)封(feng)(feng)(feng)頭(tou)(tou)(tou)(tou)、平底形(xing)(xing)封(feng)(feng)(feng)頭(tou)(tou)(tou)(tou)、錐形(xing)(xing)封(feng)(feng)(feng)頭(tou)(tou)(tou)(tou)等。

 圖4-29是材質為06Cr19Ni10各種規格的標準橢圓形封頭。

 對于非對稱形(xing)狀的工(gong)(gong)件，橢圓型(xing)(xing)封頭(tou)和各種型(xing)(xing)式(shi)的罩子，可(ke)使用熱(re)沖壓法進行加工(gong)(gong)成型(xing)(xing)。當然(ran)，熱(re)沖壓也(ye)(ye)適用于所有(you)對稱形(xing)狀的封頭(tou)成型(xing)(xing)。目前，使用的大(da)型(xing)(xing)沖壓成型(xing)(xing)設備的加工(gong)(gong)尺寸范圍都較大(da)，能(neng)加工(gong)(gong)成型(xing)(xing)的外(wai)徑達(da)29.261m、厚(hou)達(da)12.7mm的封頭(tou)。對某些尺寸和形(xing)狀，壁厚(hou)76.2mm的工(gong)(gong)件也(ye)(ye)可(ke)沖壓成型(xing)(xing)。

封(feng)頭(tou)成(cheng)型(xing)常用(yong)的方法有沖(chong)壓(ya)成(cheng)型(xing)、旋壓(ya)成(cheng)型(xing)和爆炸成(cheng)型(xing)。封(feng)頭(tou)沖(chong)壓(ya)成(cheng)型(xing)工藝(yi)流程：材料(liao)檢驗(yan)→劃線(xian)→切割(ge)下料(liao)→(厚度≥6mm的坡口加工）→組(zu)裝對(dui)焊（焊縫修磨）→加熱(re)→沖(chong)壓(ya)→余量切割(ge)→檢查(cha)驗(yan)收。