短語詞組短語circumferential welded seam 環(huán)向焊縫preparatory circumferential welding seam 預(yù)留環(huán)縫preformed circumferential welding seam 預(yù)留環(huán)縫quality of circumferential welding seam 環(huán)縫質(zhì)量circumferential seam joint 圓周接縫butt welding of circumferential seam 環(huán)縫對(duì)接焊;環(huán)縫對(duì)焊接 返回 circumferential seam