凸面: convex surface; crown对焊: butt welding法兰: flange凸面对焊法烂: raised face welding neck flange环槽式密封面对焊法兰: ring joint welding neck flange梯形槽式密封面对焊法兰: ring joint welding neck flange凹凸面对焊钢制管法兰: steel pipe welding neck flanges with male and female face for pn 0mpa; steel pipe welding neck flanges with male and female face for pn 5mpa; steel pipe welding neck flanges with male and female face for pn mpa凸面对焊钢制管法兰: steel pipe welding neck flanges with raised face for pn 0mpa; steel pipe welding neck flanges with raised face for pn 25mpa; steel pipe welding neck flanges with raised face for pn 5mpa; steel pipe welding neck flanges with raised face for pn 6mpa (bar)gb/t 8-pn 0mpa(bar)对焊法兰: welding neckflange (wnf)对焊法兰人孔: manhole with butt welded flange对焊法兰手孔: handhole with butt welded flange凹凸面对焊环板式松套钢制管法兰: loose plate steel pipe flanges with welding neck collar with male and female face凸面对焊环松套板式钢制管法兰: loose plate steel pipe flanges with welding neck collar with raised face for pn 0mpa铜合金对焊法兰: copper alloy welding neck flanges环连接面对焊钢制管法兰: steel pipe welding neck flanges with ring-joint face for pn 0mpa平面、突面对焊钢制管法兰: steel pipe welding neck flanges with flat face or raised face平面对焊钢制管法兰: steel pipe welding neck flanges with flat face for pn 25mpa; steel pipe welding neck flanges with flat face for pn 6mpa; steel pipe welding neck flanges with flat face for pn0mpa; steel pipe welding neck flanges with flat face for pn6mpa突面对焊钢制管法兰: steel pipe welding neck flanges with flat face or raised face榫槽面对焊钢制管法兰: steel pipe welding neck flanges with tongue and groove face for pn 0mpa; steel pipe welding neck flanges with tongue and groove face for pn 5mpa; steel pipe welding neck flanges with tongue and groove face for pn 6mpa接触对焊法: thomson process环连接面对焊环带颈松套钢制管法兰: loose hubbed steel pipe flanges with welding neck collar with ring-joint face突面对焊环板式松套钢制管法兰: loose plate steel pipe flanges with welding neck collar with raised face突面对焊环带颈松套钢制管法兰: loose hubbed steel pipe flanges with welding neck collar with raised face榫槽面对焊环板式松套钢制管法兰: loose plate steel pipe flanges with welding neck collar with tongue and groove face凹面对焊: concave butt weld