摘要 |
<p>A valve device which ensures reliable opening/closing control of pipeline and a stabilized operation such that even when valve opening/closing operation is quickly effected, water hammering, chattering, hunting or the like hardly occurs immediately before valve closing or at the instant of valve opening; and a pipeline system. A valve device having a valve disk adapted to move away from and into contact with a valve seat to open/close a flow path, characterized the mutually associated closure surface regions of the valve disk and valve seat are provided with uneven portions adapted to fitted to each other with a predetermined clearance therebetween in the final stage of valve closing stroke, and the flow path of the clearance between the uneven portions fitted to each other is formed having a shape to bend the direction of travel of the flowing fluid to increase the resistance loss; and a pipeline system characterized by having such valve device inserted therein.</p> |