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(chang)壓(ya)及承壓(ya)容(rong)器中(zhong)不可或缺的零(ling)部件，廣泛用于石油、電(dian)子(zi)、供暖、化工(gong)(gong)、醫藥、污水處理、輕(qing)紡、食(shi)品、機械、建筑、核電(dian)、航空航天、壓(ya)力(li)容(rong)器、軍工(gong)(gong)等行業(ye)。

封頭是壓(ya)(ya)(ya)力容(rong)(rong)器(qi)(qi)的重要受壓(ya)(ya)(ya)元件之一，它不但(dan)直接(jie)影響(xiang)容(rong)(rong)器(qi)(qi)的制造質(zhi)量(liang)和成本，而(er)且還影響(xiang)生產裝置(zhi)的安全和長期運(yun)行。常用的裝置(zhi)有反應壓(ya)(ya)(ya)力容(rong)(rong)器(qi)(qi)，熱交換壓(ya)(ya)(ya)力容(rong)(rong)器(qi)(qi)，分離壓(ya)(ya)(ya)力容(rong)(rong)器(qi)(qi)，儲存壓(ya)(ya)(ya)力容(rong)(rong)器(qi)(qi)等(deng)等(deng)。

 封(feng)頭(tou)(tou)的種(zhong)類繁(fan)多，按用途可分為(wei)承壓封(feng)頭(tou)(tou)和常壓封(feng)頭(tou)(tou)，按形(xing)狀可分為(wei)橢圓封(feng)頭(tou)(tou)、蝶形(xing)封(feng)頭(tou)(tou)、球(qiu)冠形(xing)封(feng)頭(tou)(tou)、半球(qiu)形(xing)封(feng)頭(tou)(tou)、弓形(xing)封(feng)頭(tou)(tou)、平底形(xing)封(feng)頭(tou)(tou)、錐形(xing)封(feng)頭(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(yu)非對(dui)(dui)稱形(xing)狀的(de)(de)工(gong)件，橢圓型(xing)(xing)(xing)(xing)封(feng)頭和各種型(xing)(xing)(xing)(xing)式的(de)(de)罩子，可使用熱(re)沖(chong)壓(ya)法進行加工(gong)成(cheng)型(xing)(xing)(xing)(xing)。當然，熱(re)沖(chong)壓(ya)也(ye)適用于(yu)所有(you)對(dui)(dui)稱形(xing)狀的(de)(de)封(feng)頭成(cheng)型(xing)(xing)(xing)(xing)。目前，使用的(de)(de)大(da)型(xing)(xing)(xing)(xing)沖(chong)壓(ya)成(cheng)型(xing)(xing)(xing)(xing)設備的(de)(de)加工(gong)尺寸范圍都較大(da)，能(neng)加工(gong)成(cheng)型(xing)(xing)(xing)(xing)的(de)(de)外徑達(da)29.261m、厚(hou)達(da)12.7mm的(de)(de)封(feng)頭。對(dui)(dui)某些尺寸和形(xing)狀，壁厚(hou)76.2mm的(de)(de)工(gong)件也(ye)可沖(chong)壓(ya)成(cheng)型(xing)(xing)(xing)(xing)。

封頭成型(xing)常用的(de)方法有沖(chong)壓(ya)成型(xing)、旋壓(ya)成型(xing)和爆炸成型(xing)。封頭沖(chong)壓(ya)成型(xing)工(gong)藝流程(cheng)：材(cai)料(liao)檢驗→劃線→切(qie)割下料(liao)→(厚度≥6mm的(de)坡(po)口加工(gong)）→組裝對焊（焊縫(feng)修磨）→加熱→沖(chong)壓(ya)→余(yu)量切(qie)割→檢查驗收。