ANSI B16.5 Duplex en super duplex Steel Flanges fabrikant, ASTM A182 F44, F45, F51, F53, F55, F60, F61, WN flenzen, LWN flenzen, SW flenzen, threaded flanges, bline flenzen, dus flenzen, lap plaat joint flanges, flenzen, lap joint flanges, flenzen gesicht
- Zhengzhou Huitong Pipeline Equipment Co., Ltd.