Automatic shut=off valve for gas pipelines - is controlled by timer under normal conditions, and is closed by gas pressure when pipeline fails

摘要

A forward direction closing safety valve device comprises an automatic shutting safety valve provided within a pressure transforming chamber and being controlled by a timing device under normal condition. The valve is capable of closing itself in response to the forward direction flow of the excessive high pressure gas caused upon pressure reducing failure in the pipeline passage. It will no longer be caused to open by the control of the timing device so as to achieve its objective of automatically shutting the pipeline passage off by means of the help provided by the high pressure gas in the forward direction in prevention of the disaster of gas explosion from happening accidentally.