Release assembly for a downhole tool string and method for use thereof

A method for releasing a portion of a tool string downhole of a release assembly positioned in a wellbore, the method comprising:

• providing a surface controller;
• running the tool string including a downhole controller, a plurality of downhole remote units and a plurality of release assemblies each operably associated with one of the downhole remote unit into the wellbore;
• sticking the tool string in the wellbore;
• placing the tool string in tension;
• obtaining tension information at the surface controller from the release assemblies;
• identifying the first release assembly uphole of a location wherein the tool string is stuck based upon the tension information;
• sending an actuation command to the downhole remote unit operably associated with the first release assembly via the downhole controller;
• sending an actuation signal to the first release assembly from the downhole remote unit operably associated therewith;
• and
• actuating the first release assembly to release the portion of the tool string downhole thereof by electrically actuating a first release member to enable relative axial movement between a fishing receptacle and an outer housing of the release assembly then mechanically actuating a second release member to decouple the fishing receptacle from the outer housing.

A system for releasing a portion of a tool string positioned in a wellbore, the system comprising:

• a surface controller;
• a downhole controller positioned within the tool string and operable to communicate with the surface controller;
• a plurality of downhole remote units positioned within the tool string and operable to communicate with the downhole controller;
• a release assembly positioned within the tool string and operably associated with a first one of the downhole remote units, the release assembly including an outer housing, a fishing receptacle disposed within the housing, the fishing receptacle having a fishing neck, a first release member initially coupling the fishing receptacle to the outer housing, a support assembly disposed within the housing, the support assembly having a first position wherein the support assembly engages the fishing neck to prevent relative axial movement between the fishing receptacle and the housing and a second position wherein the support assembly is disengaged from the fishing neck no longer preventing relative axial movement between the fishing receptacle and the housing and a second release member disposed within the housing, the second release member initially maintaining the support assembly in the first position;
• and
• a downhole tool positioned within the tool string downhole of the release assembly,
• wherein, an actuation command including an address of the first downhole remote unit is sent from the surface controller to the downhole controller, the actuation command is relayed from the downhole controller to the first downhole remote unit, and an actuation signal is sent from the first downhole remote unit to the release assembly to electrically actuate the second release member shifting the support assembly from the first position to the second position, and
• wherein, after shifting the support assembly to the second position, mechanical actuation of the first release member decouples the fishing receptacle and the outer housing.