1 Scope
    This standard provides flexible flange and wafer butterfly valve seal structure, technical requirements, materials, test methods and inspection rules, marking, painting, packaging, storage and transportation.
    This standard applies to: nominal pressure less than PN25, nominal size DN50 ~ DN4000 flange connection flexibility sealed butterfly valve; nominal pressure is less than PN16, nominal size DN50 ~ DN1200 the flexibility of the wafer butterfly valve seal.
    Medium non-corrosive liquids and gases, fully open position, the pipe is not more than the medium velocity 5 m / s.
2 Normative references
    The terms of the following documents by the standard reference in the provisions of this standard. Note date all reference documents, all of its subsequent amendments (Bu corrigenda of the content) or revised version of this standard are not applicable Yu, however, Gu Li of the parties under this standard Dachengxieyi study whether documents can be used Zhexie the Zuixin version . For undated reference documents, the latest versions apply to this standard.
    GB 150 steel pressure vessel
    G / T 228 Metallic materials Tensile testing method (GB / T 228-2002, eqv ISO 6892:1998)
    GB / T 9113 (all parts) Integral steel pipe flanges
    GB / T 12220 Universal Valve logo (GB / T 12220-1989, idt ISO 5209:1977)
    GB / T 12221 Metal valve structure length (GB / T 12221 2005, ISO 5752:1982, MOD)
    GB / T 12223 part of the turn valve actuator attachment (GB / T 12223-2005, ISO 5211:1991, MOD)
    GB / T 12224 General requirements for steel valves (GB / T 12224-2005, ASTM B16.34a-1998, NEQ)
    GB / T 12226 Universal Valve gray iron castings
    GB / T 12227 Universal Valve ductile iron castings
    GB / T 12228 Universal Valve carbon steel forgings
    GB / T 12229 General requirements valve of carbon steel castings
    GB / T 13927 Industrial valve pressure test (GB / T 13927-2008, ISO / DIS 5208:2007, MOD)
    GB / T 17219-1998 in drinking water equipment and protective materials, safety evaluation
    GB / T 17241.6 whole cast iron pipe flanges (GB / T 17241.6-1998, neq ISO 7005.2:1988)
    GB / T 17241.7 cast iron pipe flanges (GB / T 17241.7-1998, neq ISO 7005.2:1988)
    JB / T 106 signs and paint the valve
    JB / T 5300 material selection guidelines for industrial valves
    JB / T 7928 General requirements valve supplier