【运输】成螺旋形布置装配，接合面【运输】成螺旋形排列的，接缝

helically arranged, seam manufacture

helically arranged folded seam

tube with helically arranged seam

seam, helically arranged metal hose, tube

helically-shaped, groove

winding of tubes with helically arranged seams in moulds

helically, coiling

helically