埋弧焊在拼焊中等厚度304不銹(xiu)鋼鋼板上應用較為廣泛。圖3-30為一個容器筒體的展開圖,由6塊不銹(xiu)鋼板焊接而成的。操作步驟如下:

1. 分別先組焊(han)(han)Z1三(san)對不(bu)銹鋼板:將(jiang)其緊(jin)壓(ya)裝配在焊(han)(han)接(jie)夾具(見(jian)圖3-17)上進行雙面(mian)對接(jie)埋弧(hu)焊(han)(han)。具體(ti)焊(han)(han)接(jie)參數(shu)為:第(di)一面(mian)焊(han)(han)接(jie)電(dian)(dian)(dian)(dian)(dian)流500A,電(dian)(dian)(dian)(dian)(dian)弧(hu)電(dian)(dian)(dian)(dian)(dian)壓(ya)32V,焊(han)(han)接(jie)速度為450mm/min;第(di)二面(mian)焊(han)(han)接(jie)電(dian)(dian)(dian)(dian)(dian)流580A,電(dian)(dian)(dian)(dian)(dian)弧(hu)電(dian)(dian)(dian)(dian)(dian)壓(ya)33V,焊(han)(han)接(jie)速度為450mm/min。兩面(mian)均為φ4mm焊(han)(han)絲,采用(yong)直流反接(jie)電(dian)(dian)(dian)(dian)(dian)源(yuan)。

2. 對Z1的(de)三塊不銹鋼板的(de)焊縫表面質量進行檢查,并局部矯平焊接變形。
3. 組焊(han)Z2的兩組焊(han)縫,裝配(pei)時要求各板與(yu)Z,焊(han)縫之(zhi)間錯(cuo)位距離不小于200mm,緊壓(ya)裝配(pei)在焊(han)接(jie)夾(jia)具(圖(tu)3-16)中,按上(shang)述Z,的焊(han)接(jie)參(can)數(shu)進行焊(han)接(jie)。

4. Z2兩組焊縫焊接完畢,檢查焊縫表面質量,然后在卷板機上卷圓,卷圓成形后的三組S焊縫由焊條電弧焊完成。無論采用雙面對接埋弧(hu)焊還是焊(han)條電(dian)弧焊(han),接觸介質的焊縫(即筒內焊縫)均要最后施焊,以提高耐蝕性。經X射線檢測不合格的焊縫采用焊條電弧焊進行修補。

