| 摘要 |
<p>A valve device for use downhole is described as comprising a body member and a channel through the body member through which fluid can flow. A moveable member is mounted within the body member, and comprises an obturating member for selectively obturating the channel. The moveable member is moveable between a first position in which the channel is not obturated and fluid flow through the channel is permitted, and a second position in which the channel is obturated and fluid flow through the channel is substantially prevented. A method of preventing the fluid flow downhole is also described as comprising the steps of inserting a downhole tool comprising a valve device according to the present invention downhole and moving the moveable member from the first to the second position such that the obturating member obturates the channel.</p> |
