埋弧自动焊焊接压力容器时,用传统的方法将小车放置在升降台上焊接筒体环缝,所得焊缝质量极不稳定,焊缝成形差,时有焊瘤、焊偏等缺陷,焊缝宽度差超标,拍片合格率很低.经分析,其原因有以下几方面:(1)筒体存在椭圆度,导致焊嘴与简体坡口的间距发生变化.筒体直径越大,壁厚越薄,椭圆度越大. Submerged arc welding automatic welding pressure vessel, the traditional method of placing the car on the lifting platform welding cylinder ring seam, the resulting weld quality is extremely unstable, poor weld formation, sometimes welding defects such as welding, welding, welding The difference of seam width is beyond the standard, the passing rate of the film is very low.Through the analysis, the reasons are as follows: (1) The ellipticity of the cylinder exists, resulting in the change of the distance between the welding nozzle and the simplified groove. The thinner, the greater ovality.