| abstract |
(57) [Summary] [PROBLEMS] To purge gas remaining in a primary side pipe with high efficiency, and to stop a vacuum generator while pressurizing the primary side pipe during a pressurized standing purge and immediately preceding purge. Let it. SOLUTION: A cylinder 1 accommodating a gas 22 includes a cylinder base valve 23, a filling pipe 2, a primary pipe 14, It is connected to the supply side via the air operated valve 6, the pressure reducing valve 7, the secondary pipe 19 and the air operated valve 10. Inert gas 15 flows into primary pipe 14 via air operated valve 13. The primary pipe is connected to the vacuum generator 11 via the air operated valve 5 and the pipe 20. The residual gas in the primary side pipe is discharged into the primary side pipe by automatically performing the pressure left purge in which the pressurized standing by the inert gas for 2 to 10 minutes and the evacuation for 20 seconds are repeatedly performed. Purge as 18. |