socket-welding fitting 焊接式管接头

butt-welding fitting 对口熔接接头

quality inspection before welding fitting 焊接前装配质量检查

welding-fitting 装焊

sequence of fitting and welding 装配焊接顺序

Welding and fitting 焊接及装配 ; 焊接与装配 ; 焊接和装配

welding and fitting platform 焊合台

welding pipe fitting 焊接管接头

fitting and welding 配合与焊接