| 摘要 |
The present invention relates to a polyethylene ball valve. According to the present invention, a ball valve body is formed of a polyethylene material, thus gas leakage attributable to metal corrosion can be prevented. A valve seat portion that is in contact with an outer circumferential surface of the ball in the valve body and is formed for the connection flow path-direction side surface to be exposed is formed, and the polyethylene ball valve is formed for the flat surface portion excluding a passage to be in surface-contact with the valve seat portion when opened and for a circular portion to be in press contact with the valve seat portion when closed. Accordingly, the valve seat portion is not compressed when the polyethylene ball valve is opened, thus a deformation of the valve seat portion is minimized and durability is improved. Also, a deceleration gear with a gear ratio of 50:1 to 80:1 is provided so that the ball can be opened/closed even with a slight force. In addition, the present invention can be operated even at a high pressure and can have improved durability from reduced adapter and stem loads. |
