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Specifies requirements for two types of predominantly key-operated valves for underground use with flanges or spigot ends or socket ends. The two types shall be specified as type A or type B and shall include the following features: inside screw stem; wedge or parallel obturator; metallic or elastomeric obturator seatings; metallic or elastomeric body seatings; ferrous metal and/or copper alloy trims; T-key operation; ring key and bar operation. Type A valves are for T-key operation; type B valves are for ring key and bar operation.
|Engelse titel||Predominantly key-operated cast iron gate valves for underground use|