Drilling string back off sub apparatus and method for making and using same

A method for disconnecting a drill string comprising the steps of:

• providing a drill string including one back-off sub or a plurality of back-off subs disposed at a desired location or desired locations along a length of the string, where each sub is capable of independent activation and comprises an apparatus comprising:
• an upper portion including:
• a control section and
• a translational section having:
• a first sub connector,
• a first string connector, and
• a lower portion including:
• an abandonment section having:
• a second sub connector, and
• a second string connector,
• where the upper section and the lower section are connected together via the sub connectors forming a sub connection and where the apparatus is adapted to be placed in the drill string via the string connectors so that the drill string can be disconnected at the sub-connection by rotating the first sub connector relative the second sub connector, leaving the abandonment section and a portion of the string downstream of the abandonment section,
• lowering the string into a well,
• activating one of the subs in the string to overcome a make-up force holding the sub connection tight where the translation section is adapted to rotate the first sub connector relative the second sub connector breaking the sub connection, and
• rotating the string upstream of the sub to disconnect at the sub-connection.

An apparatus comprising:

• a plurality of pipe sections having first and second connectors for forming connections between the pipe sections to form a string of pipes,
• one sub or a plurality of subs disposed at one or a plurality of desired locations along the string, where each sub comprises:
• an upper portion including:
• a control section including:
• a catcher including a plurality of ports,
• a holding means,
• a stop adapted to stop the downward motion of the catcher in response to the activation pressure,
• a plurality of conduits, and
• a hydraulic chamber connected to the plurality of conduits,
• where the catcher is adapted to catch a ball, the holding means is adapted to hold the catcher in place until the catcher catches the ball and is exposed to an activation pressure and to allow the catcher to move downward in response to the activation pressure, the stop is adapted to align the ports and the conduits, the conduits are adapted to allow fluid to flow into the chamber and the chamber is adapted to fill and push against a top of the translational section causing the translational section to move downward with sufficient torque to overcome a make-up force holding the sub connection tight, and
• a translational section having:
• a first sub connector,
• a first string connector, and
• a lower portion including:
• an abandonment section having:
• a second sub connector, and
• a second string connector,
• wherein the upper section and the lower section are connected together via the sub connectors forming a sub connection and where the apparatus is adapted to be placed in a drill string via the string connectors so that the drill string can be disconnected at the sub-connection by rotating the first sub connector relative the second sub connector, leaving the abandonment section and a portion of the string downstream of the abandonment section and where the string is capable of being disconnected independently at each sub.