| 摘要 |
<P>PROBLEM TO BE SOLVED: To surely prevent a valve body rubber seat of a butterfly valve from slipping off and to reduce opening/closing torque of a valve body. <P>SOLUTION: Entire sliding contact portion of the valve body rubber seat 10 pinch-held by a valve plate 8 fixed to a valve bar 3 and a seat retainer 9 fixed to the valve plate 8 against a valve case valve seat 2d is coated with super-high molecular polyethylene, thereby friction force between the rubber seat 10 and the valve case valve seat 2d is reduced and the opening/closing torque of the valve body 4 is suppressed. Also, due to hardly-elongated property of the coating, deformation of the rubber seat 10 in the diameter-expanding direction is suppressed, and thereby the rubber seat 10 can be surely prevented from slipping off. <P>COPYRIGHT: (C)2012,JPO&INPIT |
