摘要 |
<p>A wellbore system comprising a casing, and a pressure testing valve incorporated within the casing and comprising a sleeve positioned within a housing and transitional from a first to a second position, and from the second to a third position, wherein, when the sleeve is in the first and second positions, the sleeve blocks a route of fluid communication via one or more housing ports and, when the sleeve is in the third position the sleeve does not block fluid communication, wherein the pressure testing valve is configured such that a force in the direction of the second position to the sleeve causes the sleeve to transition to the second position, and wherein the pressure testing valve is configured such that a reduction of the force in the direction of the second position to the sleeve causes the sleeve to transition to the third position.</p> |