Product DescriptionR-71800 series high performance butterfly valve feature triple eccentric design which provide zero friction between dick and seal in 0-90° rotation. Multi level of seat that mixed with mental and non-metal material, effectively protect the valve from leakage. They are frequently applied in high temperatures services.Product Parameters      (1)Trim: Multi-level Valve Seat  Triple Eccentric Structure(2)Body : Straight(3)Bonnet: Standard       (4)Temperature Range : -196℃~538℃(5)Plug sealing : Standard  Graphite  (6)Leakage :CLASS VI   (7)Flow characteristic : Approximate  Equal% (8)Pipe Line Connection : Flange  Wafer(9)Range ability : 30:1