| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a gas piping shutting off device capable of shutting off a gas flow channel at occurrence of a fire or the like. <P>SOLUTION: In the gas piping shutoff device, a socket 5 for interconnecting gas pipes 1 and 2 is constituted by a cylindrical member made of cast iron. An escape groove 6A for screw machining is formed in the center of the inner peripheral surface of the socket 5, and an expansible fire-proofing packing material 10 is arranged in the escape groove 6A. This packing material 10 is formed of an expansible material containing graphite. When the fire or the like occurs to increase temperature of the gas pipes 1 and 2 and the socket 5, the packing material 10 in the socket 5 expands so as to extrude into the gas flow channel, and the gas flow channel is buried with the expanding packing material 10' to block the flow channel. <P>COPYRIGHT: (C)2004,JPO |
