| 摘要 |
A downhole pressure isolation tool is disclosed for use in a tubing string or casing string. The tool includes a frangible disk or seal within a housing having a bore. The disk has a dome section and a cylinder section and the dome of the disk is transverse to the bore. A piston is located between the housing and the cylinder of the disk, the piston movable between a first position and a second position, the second position, engaging a set of fingers which push into the cylinder of the disc to break it, causing the entire disk the cause and the entire disk to fail. A rupturable membrane is provided which, when it ruptures places the piston in fluid communication with a fluid within the bore. |
| 主权项 |
1. A downhole well isolation tool comprising:
a housing having an upper end and a lower end, the housing having an exterior wall and having an interior wall, the housing defining a bore having a bore axis; an upper frangible disk, the frangible disk having an outer wall and an inner wall, a cylindrical section and a generally hemispherical dome, the upper frangible disk engaging the inner wall of the housing so the dome is convex when viewed from the upper end of the housing, the frangible disk in an unbroken state substantially blocking the bore, and defining an upper bore above the frangible disk and a lower bore below the frangible disk; a finger assembly comprising multiple fingers, each finger having a first position and a second position, at least a portion of some of the multiplicity of fingers adjacent the frangible disk cylindrical section outer wall when in the first position and inward from the first position when in the second position; a piston assembly engaging the housing interior wall, the piston assembly comprising a piston and “O” rings engaged therewith, the piston including a piston wall, the piston slideable with respect to the housing interior wall and the fingers of the finger assembly between a first, uphole position and a second, downhole position; a rupturable membrane assembly having a rupturable membrane, the rupturable membrane assembly in fluid connection with the upper bore, the rupturable membrane capable of rupturing at a membrane rupture pressure; a head space defined by a portion of the housing interior wall and a portion of the piston wall and sealing elements there between, the head space not in substantial fluid communication with the upper bore before the membrane ruptures and in fluid communication with the upper bore when the membrane ruptures; wherein the piston is moveable from the first position toward the second position, responsive to rupture of the rupturable membrane; and wherein the movement of the piston toward the second position causes the piston to engage at least some of the fingers and force them from the first position to the second position and into the cylindrical section of the upper frangible disk with sufficient force to break the frangible disk and unblock the bore. |
