| 摘要 |
PURPOSE:To provide a fireproof seal for valves used in various pipes of a ship or the like, which is capable of preventing leakage of fluid in the pipe, by interposing a packing in the form of a hollow metal O-ring in an annular space formed between a valve seat and a retainer. CONSTITUTION:A seal packing 1 made of a fluoroplastics is supported by an annular spring 2. The top 3 of the seal packing 1 is held in contact with a valve plate 4 while the other end 5 is fitted in a groove 7 formed in a valve seat 6. Further, a flange section 8 of the seal packing 1 is subjected to the biasing force of a conical disk spring 9 that is kept in a compressed state, so that the valve can be sealed. Further, a packing 12 in the form of a hollow metal O-ring is fitted in a recess 11 formed in a retainer 10. The conical disk spring 9 is kept under compression by a bolt 17 screwed into a fit ring 16 by the intermediary of a spring retainer 18. With such an arrangement, if the packing 1 is brunt out at the time of a fire or the like, the retainer 10 is forced to the right through deformation of the spring 9 and compresses the packing 12 while keeping metal contact with the valve plate 4, so that the valve can be sealed. |
