Automatic tubing release

A method of automatically releasing a perforating apparatus from a tubing, comprising the steps of:

• conducting a detonation wave through a detonating cord, said detonating cord begin disposed within an interior of a frangible member and connected to said perforating apparatus;
• directing the propagation of said detonation wave initially through said interior of said frangible member and subsequently toward said perforating apparatus;
• shattering said frangible member in response to said detonation wave conducting through said detonating cord;
• and
• releasing said perforating apparatus from said tubing only after said frangible member shatters.

Apparatus for controlling the movement of a piston in a well tool in the presence of a hydrostatic pressure of a wellbore fluid when said well tool is disposed in a wellbore and for disconnecting a perforating apparatus from a tubing in response to said movement, comprising:

• frangible means including a hollow interior for preventing said wellbore fluid from exerting said hydrostatic pressure on said piston, said piston not moving and remaining stationary when said wellbore fluid is not exerting said hydrostatic pressure on said piston;
• and
• means for shattering said frangible means, said wellbore fluid exerting said hydrostatic pressure on said piston when said frangible means shatters, said piston moving in response to said hydrostatic pressure, said perforating apparatus being disconnected from said tubing in response to the movement of said piston,
• the means for shattering said frangible means including a detonating cord adapted for conducting a detonation wave disposed within said hollow interior of said frangible means, said frangible mean shattering in response to said detonation wave conducting within said detonating cord and propagating within the hollow interior of said frangible means.

A release apparatus adapted to be connected between a perforating apparatus and a tubing for releasing the perforating apparatus from the tubing, comprising:

• means for connecting said perforating apparatus to said tubing;
• frangible means having a hollow center ad adapted to shatter for maintaining the connection between the perforating apparatus and the tubing by said means for connecting when the frangible means remains intact and has not shattered;
• and
• detonating cord means disposed within the hollow center of said frangible means and connected to said perforating apparatus for conducting a detonation wave through said frangible means and toward said perforating apparatus.
• said frangible means shattering in response to said detonation wave conducting within said detonating cord means,
• said perforating apparatus detonating in response to said detonation wave,
• said perforating apparatus being released form said tubing when said frangible means shatters.

A method of releasing a perforating apparatus form a tubing, comprising the steps of:

• conducting a detonation wave in a detonating cord and propagating said detonation wave through an interior of a frangible member;
• shattering said frangible member when the detonation wave in said detonating cord passes through said frangible member;
• shifting a release piston in release piston in response to the shattering step;
• and
• releasing the perforating apparatus from the tubing in response to the shifting step.

Release apparatus adapted to be connected between a device and a tubing in a wellbore for releasing the device form the tubing, comprising:

• a frangible apparatus having a hollow interior, said frangible apparatus being comprised of a cast iron material;
• detonating cord means disposed with the hollow interior of said frangible apparatus for conducting a detonation wave, said detonation wave shattering the cast iron material of said frangible apparatus when said detonation wave conducts through said frangible apparatus;
• and
• connection means for maintaining a connection between the device and the tubing before the frangible apparatus shatters and disengaging said connection between the device and the tubing after the frangible apparatus shatters.

A method of releasing a device form a tubing in a wellbore, comprising the steps of:

• conducting a detonation wave in a detonating cord through an interior of a frangible member, said frangible member being comprised of a cast iron material;
• shattering the cast iron material of said frangible member when the detonation wave conducts through the interior of said frangible member;
• and
• releasing the device form the tubing in response to the shattering step.

A method of releasing a device from a tubing in a wellbore, comprising the steps of:

• conducting a detonation wave in a detonating cord and propagating the detonation wave through an interior of a frangible member;
• shattering said frangible member when the detonation wave propagates through said interior of said frangible member;
• shifting a release piston when said frangible member is shattered in response to the detonation wave propagating through the frangible member;
• and
• releasing the device from the tubing in response to the shifting step.