Abstract: A system is described for forming a debris barrier downhole in a wellbore. The system may include a mandrel, a retrievable downhole tool, and a debris ring. The mandrel may be positionable within a wellbore. The retrievable downhole tool may be positionable around the mandrel to perform tasks downhole in the wellbore. The debris ring may include an expandable material positionable around the mandrel to form a debris barrier. The debris barrier may be formed in response to exposing the expandable material to wellbore fluid.

Abstract: A system is described for forming a debris barrier downhole in a wellbore. The system may include a mandrel, a retrievable downhole tool, and a debris ring. The mandrel may be positionable within a wellbore. The retrievable downhole tool may be positionable around the mandrel to perform tasks downhole in the wellbore. The debris ring may include an expandable material positionable around the mandrel to form a debris barrier. The debris barrier may be formed in response to exposing the expandable material to wellbore fluid.

Abstract: A downhole tool includes a housing including a connection for coupling with a conveyance that extends from a terranean surface into a wellbore; a first tubular member coupled with the housing, the first tubular member including a first compound cylinder; and a second tubular member coupled with the housing and concentrically positioned radially adjacent the first tubular member, the second tubular member including a second compound cylinder, the first and second tubular members defining a pressure chamber between an inner surface of the first tubular member and an outer surface of the second tubular member.

Abstract: A downhole tool includes a housing including a connection for coupling with a conveyance that extends from a terranean surface into a wellbore; a first tubular member coupled with the housing, the first tubular member including a first compound cylinder; and a second tubular member coupled with the housing and concentrically positioned radially adjacent the first tubular member, the second tubular member including a second compound cylinder, the first and second tubular members defining a pressure chamber between an inner surface of the first tubular member and an outer surface of the second tubular member.

Abstract: A packer (80) for establishing sealing engagement with a surface disposed in a wellbore includes a packer mandrel (90) and a seal assembly (100, 102, 104) slidably disposed about the packer mandrel (90). The seal assembly (100, 102, 104) has a running position and a radially expanded sealing position. A piston (122) is slidably disposed about the packer mandrel (90) and operably associated with the seal assembly (100, 102, 104). A release assembly 145 is disposed about the packer mandrel (90) and is releasably coupled to the piston (122) such that actuation of the release assembly (145) decouples the release assembly (145) from the piston (122) allowing the piston (122) to shift longitudinally relative to the packer mandrel (90) to operate the seal assembly (100, 102, 104) from the running position to the radially expanded sealing position, thereby setting the packer (80).

Abstract: A packer (80) for establishing sealing engagement with a surface disposed in a wellbore includes a packer mandrel (90) and a seal assembly (100, 102, 104) slidably disposed about the packer mandrel (90). The seal assembly (100, 102, 104) has a running position and a radially expanded sealing position. A piston (122) is slidably disposed about the packer mandrel (90) and operably associated with the seal assembly (100, 102, 104). A release assembly 145 is disposed about the packer mandrel (90) and is releasably coupled to the piston (122) such that actuation of the release assembly (145) decouples the release assembly (145) from the piston (122) allowing the piston (122) to shift longitudinally relative to the packer mandrel (90) to operate the seal assembly (100, 102, 104) from the running position to the radially expanded sealing position, thereby setting the packer (80).

Abstract: An apparatus for actuating a downhole tool within a well bore comprises a cylindrical mandrel extending longitudinally through the downhole tool; an interventionless, hydrostatic, top-down actuating piston disposed about the mandrel and forming a first chamber and a second chamber therebetween; and a rupture disk that prevents fluid communication between the well bore and the first chamber until sufficient hydrostatic pressure is applied to the well bore to fail the rupture disk. A method of actuating a downhole tool comprises connecting a top-down actuating module to the downhole tool, running the downhole tool to a desired depth within a well bore, pressuring up the well bore without pressuring up an internal flow bore extending through the top-down actuating module, hydrostatically actuating an upper piston of the top-down actuating module to exert an actuation force onto the downhole tool, and actuating the downhole tool.