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(feng)頭是常壓及承壓容器(qi)中不可或(huo)缺的零部件(jian)，廣泛用(yong)于石油、電子(zi)、供(gong)暖、化工、醫藥、污水處理、輕(qing)紡、食品、機械、建筑、核電、航(hang)空(kong)航(hang)天、壓力(li)容器(qi)、軍(jun)工等行業。

封(feng)頭是壓(ya)(ya)力(li)容(rong)(rong)器的重要受壓(ya)(ya)元件之一，它不但直接(jie)影響(xiang)(xiang)容(rong)(rong)器的制造質量和成本(ben)，而且(qie)還影響(xiang)(xiang)生產裝置(zhi)(zhi)的安(an)全和長(chang)期(qi)運行。常用的裝置(zhi)(zhi)有(you)反應壓(ya)(ya)力(li)容(rong)(rong)器，熱交(jiao)換壓(ya)(ya)力(li)容(rong)(rong)器，分離壓(ya)(ya)力(li)容(rong)(rong)器，儲存壓(ya)(ya)力(li)容(rong)(rong)器等等。

 封(feng)頭(tou)(tou)(tou)的(de)種類繁多，按(an)用(yong)途可分(fen)為承壓封(feng)頭(tou)(tou)(tou)和(he)常壓封(feng)頭(tou)(tou)(tou)，按(an)形(xing)狀可分(fen)為橢圓封(feng)頭(tou)(tou)(tou)、蝶(die)形(xing)封(feng)頭(tou)(tou)(tou)、球(qiu)冠形(xing)封(feng)頭(tou)(tou)(tou)、半球(qiu)形(xing)封(feng)頭(tou)(tou)(tou)、弓形(xing)封(feng)頭(tou)(tou)(tou)、平底形(xing)封(feng)頭(tou)(tou)(tou)、錐形(xing)封(feng)頭(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(dui)(dui)于非對(dui)(dui)稱形狀的(de)工(gong)(gong)件，橢圓型(xing)(xing)封頭和(he)各(ge)種(zhong)型(xing)(xing)式的(de)罩子，可使用熱沖壓(ya)法進行加(jia)工(gong)(gong)成(cheng)(cheng)(cheng)型(xing)(xing)。當然，熱沖壓(ya)也適用于所有(you)對(dui)(dui)稱形狀的(de)封頭成(cheng)(cheng)(cheng)型(xing)(xing)。目前(qian)，使用的(de)大型(xing)(xing)沖壓(ya)成(cheng)(cheng)(cheng)型(xing)(xing)設備(bei)的(de)加(jia)工(gong)(gong)尺寸范圍(wei)都較大，能加(jia)工(gong)(gong)成(cheng)(cheng)(cheng)型(xing)(xing)的(de)外徑達29.261m、厚達12.7mm的(de)封頭。對(dui)(dui)某些尺寸和(he)形狀，壁厚76.2mm的(de)工(gong)(gong)件也可沖壓(ya)成(cheng)(cheng)(cheng)型(xing)(xing)。

封頭成(cheng)型(xing)(xing)常用的方法有沖(chong)(chong)壓成(cheng)型(xing)(xing)、旋壓成(cheng)型(xing)(xing)和爆炸成(cheng)型(xing)(xing)。封頭沖(chong)(chong)壓成(cheng)型(xing)(xing)工(gong)藝流程：材料檢驗→劃線→切(qie)割(ge)下料→(厚(hou)度≥6mm的坡口(kou)加工(gong)）→組裝對焊(han)（焊(han)縫修磨(mo)）→加熱→沖(chong)(chong)壓→余量(liang)切(qie)割(ge)→檢查驗收。