| 摘要 |
A gas supply system cquipped with cylinders. in which the fear of a dangerous feed gas flowing backward to a purge gas introduction line and the likes can be prevented, is provided. [Construction] A piping portion B1 which becomes a negative pressure area is demarcatedly formed in a purge gas introduction line B by arranging two valves V3 and V7 in series therein, and in the piping portion B1 demarcatedly formed by these two valves V3 and V7, a gas in the piping portion B1 is led to a vent line D through a vent line D2 having a third valve V8 provided therein, and a pressure sensor 12 is placed for detecting the gas pressure in the piping portion B1. If any trouble takes place in the valve V3 or valve V8, a raise in pressure will be generated in the piping portion B1 in which the inner volume thereof is made small. By detecting this raise in pressure by the pressure sensor 12, the fear of a feed gas flowing backward to the purge gas introduction line B can be quickly detected. |
