A method of setting a tandem releasable bridge plug system in a casing includes assembling a tandem bridge plug string including a lower bridge plug on a lower, disconnectable connector, an upper bridge plug on an upper, disconnectable connector which both are initially disabled by a lock and unlockable from topsides, and running in the tandem plug string on a drill pipe string until the lower plug is at its setting target depth; setting and shutting the lower plug; disconnecting the upper plug from the lower plug; pulling up the upper plug to its upper setting target depth; enabling the upper plug by releasing the lock; setting and shutting the upper plug; disconnecting the drill pipe string from the upper plug.

A method of setting a tandem releasable bridge plug system in a casing includes assembling a tandem bridge plug string including a lower bridge plug on a lower, disconnectable connector, an upper bridge plug on an upper, disconnectable connector which both are initially disabled by a lock and unlockable from topsides, and running in the tandem plug string on a drill pipe string until the lower plug is at its setting target depth; setting and shutting the lower plug; disconnecting the upper plug from the lower plug; pulling up the upper plug to its upper setting target depth; enabling the upper plug by releasing the lock; setting and shutting the upper plug; disconnecting the drill pipe string from the upper plug.

An oil or gas well fishing tool (60). The downhole fishing tool (60) has a receptacle (61) that is open at one end. The tool also has deployment tool engaging means (62), located on the opposite end of the receptacle (61) to the one end. The tool further has a layer of an alloy (64) provided on the interior surface of the receptacle (61). The alloy is a eutectic alloy and/or a bismuth alloy. The tool further comprises heating means (65) to heat the alloy (64) so that it melts and can flow over any object received within the receptacle (61).

An oil or gas well fishing tool (60). The downhole fishing tool (60) has a receptacle (61) that is open at one end. The tool also has deployment tool engaging means (62), located on the opposite end of the receptacle (61) to the one end. The tool further has a layer of an alloy (64) provided on the interior surface of the receptacle (61). The alloy is a eutectic alloy and/or a bismuth alloy. The tool further comprises heating means (65) to heat the alloy (64) so that it melts and can flow over any object received within the receptacle (61).

Systems and methods for actuation of downhole devices are disclosed. The system includes a first cylindrical pipe having one or more first materials attached to an outer surface of the first cylindrical pipe, a second cylindrical pipe co-axial with the first cylindrical pipe and having a diameter greater than the first cylindrical pipe, the second cylindrical pipe comprising one or more second materials disposed on an inner surface of the second cylindrical pipe, wherein the first materials generate one or more signals when the first materials come in contact with the second materials, and a digital logic circuit configured to receive the one or more signals as input, and generate an output based on the input, the output configured for actuation of the downhole devices.

Systems and methods for actuation of downhole devices are disclosed. The system includes a first cylindrical pipe having one or more first materials attached to an outer surface of the first cylindrical pipe, a second cylindrical pipe co-axial with the first cylindrical pipe and having a diameter greater than the first cylindrical pipe, the second cylindrical pipe comprising one or more second materials disposed on an inner surface of the second cylindrical pipe, wherein the first materials generate one or more signals when the first materials come in contact with the second materials, and a digital logic circuit configured to receive the one or more signals as input, and generate an output based on the input, the output configured for actuation of the downhole devices.

A system for facilitating fluid flow to a wellbore includes a packer having a first conduit and a second conduit adjacent to the first conduit. A portion of the second conduit is formed by an outer surface of the first conduit. The packer also includes a swelling element that surrounds and radially encloses the first conduit and second conduit. The first end of the packer includes a bulkhead manifold having a transition section that forms a fluid coupling from at least one external bypass conduit to the second conduit, and the swelling element is operable to form a seal against a wellbore wall upon exposure to a swell fluid. The first end of the packer is fluidly coupled to the fluid supply source via an external bypass conduit, and the second conduit is fluidly coupled to the annulus of the wellbore at the second end of the annulus bypass packer.

A system for facilitating fluid flow to a wellbore includes a packer having a first conduit and a second conduit adjacent to the first conduit. A portion of the second conduit is formed by an outer surface of the first conduit. The packer also includes a swelling element that surrounds and radially encloses the first conduit and second conduit. The first end of the packer includes a bulkhead manifold having a transition section that forms a fluid coupling from at least one external bypass conduit to the second conduit, and the swelling element is operable to form a seal against a wellbore wall upon exposure to a swell fluid. The first end of the packer is fluidly coupled to the fluid supply source via an external bypass conduit, and the second conduit is fluidly coupled to the annulus of the wellbore at the second end of the annulus bypass packer.

A modular pressure cylinder for a downhole tool has an active mandrel tube that supports a modular pressure cylinder. Pistons of the modular pressure cylinder are respectively interconnected and cylinder walls of modular pressure cylinder are respectively interconnected. When fluid is pumped through a tubing string into the downhole tool, the pistons are urged in one direction while the cylinder walls are urged in an opposite direction along an axis of the active mandrel tube.

A modular pressure cylinder for a downhole tool has an active mandrel tube that supports a modular pressure cylinder. Pistons of the modular pressure cylinder are respectively interconnected and cylinder walls of modular pressure cylinder are respectively interconnected. When fluid is pumped through a tubing string into the downhole tool, the pistons are urged in one direction while the cylinder walls are urged in an opposite direction along an axis of the active mandrel tube.