Seat assembly for use in fracturing subsurface geologic formations

Abstract

An embodiment of a seat assembly cooperates with an isolation member to isolate a well first portion from a well second portion and comprises one of a recess or a chamber to receive an explosive charge. A pressure sensor, a circuit, and a battery may also be received into the same or other recess(es) or chamber(s) to trigger detonation, or a tool may be run into the well to engage and detonate the explosive charge. The seat assembly is secured in the well casing by at least one deployable gripping component and it resists deformation under the application of a substantial pressure differential across the seat and an isolation member sealably engaged therewith. Detonation of the explosive charge disables the at least one gripping component, thereby enabling retrieval of a body of the seat assembly to the surface using a tool coupled to a wireline or a coiled tubing string.

What is claimed is: 
     
         1 . An isolation member seat assembly, for sealably receiving an isolation member, securable in a set position in a well casing in a well to isolate a pressure within a well first portion from a pressure in a well second portion, the isolation member seat comprising:
 a body having a proximal end, a bore therethrough and at least one of a chamber and a recess within the body;   at least one gripping component coupled to the body and movable from a retracted position to a deployed position to engage the well casing and to secure the body in the well casing;   a seat at the proximal end of the body to sealably engage the isolation member;   a battery received within the at least one of a chamber and a recess of the body;   an explosive charge including an explosive material received within the at least one of a chamber and a recess of the body;   a pressure sensor received within the at least one of a chamber and a recess of the body, the pressure sensor disposed in fluid communication an exterior surface of the body and adapted to generate a signal upon sensing a predetermined pressure; and   a circuit received within the at least one of a chamber and a recess of the body, the circuit conductively coupled to receive a signal from the pressure sensor and to generate a current to the explosive charge in response thereto;   wherein detonation of the explosive charge disables at least one of the at least one gripping member and the at least one displacement member to release the body from the secured position within the well casing.   
     
     
         2 . The isolation member seat assembly of  claim 1 , wherein the at least one gripping component comprises at least one slip coupled to the body of the seat assembly, the at least one slip movable from a retracted position to a deployed position. 
     
     
         3 . The isolation member seat assembly of  claim 2 , wherein the at least one gripping component further comprises at least one displacement member coupled to the body adjacent to at least one slip, the at least one displacement member movable from a run-in position to an engaged position to engage and displace the at least one adjacent slip from the retracted position to the deployed position and to thereby secure the seating assembly in a position at a targeted position in the well casing. 
     
     
         4 . The isolation member seat assembly of  claim 1 , wherein the at least one gripping component comprises a plurality of gripping components coupled to the body of the seat assembly and angularly spaced about an axis of the seat assembly. 
     
     
         5 . An isolation member seat assembly, for sealably receiving an isolation member, securable in a set position in a well casing in a well to isolate a pressure within a well first portion from a pressure in a well second portion, the isolation member seat comprising:
 a body having a proximal end, a bore therethrough and at least one of a chamber and a recess within the body;   at least one gripping component coupled to the body and movable from a retracted position to a deployed position to engage the well casing and to secure the body in the well casing;   at least one explosive charge disposed in one of a chamber and a recess in the body proximal to the at least one gripping component;   a seat at the proximal end of the body to sealably engage the isolation member; and   at least one conductive lead coupled at a distal end to the at least one explosive charge and at a proximal end to at least one contact secured to the body;   wherein detonation of the at least one explosive charge disables the at least one slip to release the seat assembly from a secured position within the well casing; and   wherein the contact is disposed in a position on the body for engagement by a tool positioned within the well casing to engage the seat assembly.   
     
     
         6 . The isolation member seat assembly of  claim 5 , wherein the tool is positionable within the well casing using one of a wireline and a coiled tubing string. 
     
     
         7 . The isolation member seat assembly of  claim 5 , wherein the tool engages the contact and introduces an electrical current through the at least one contact and the at least one conductive lead to the explosive charge to detonate the at least one explosive charge. 
     
     
         8 . The isolation member seat assembly of  claim 5 , wherein the at least one gripping component comprises two or more gripping components angularly spaced about the axis of the seat assembly. 
     
     
         9 . The isolation member seat assembly of  claim 5 , wherein the at least one gripping component of the seat assembly comprises at least one slip movable from a retracted position to a deployed position to engage and grip the well casing and to thereby secure the seat assembly in a targeted position within the well casing. 
     
     
         10 . The isolation member seat assembly of  claim 9 , wherein the eat least one gripping component of the seat assembly comprises at least one displacement member disposed adjacent to the at least one slip, the at least one displacement member coupled to the body of the seat assembly and movable from a run-in position to an engaged position to engage and deploy the at least one slip to the deployed position. 
     
     
         11 . The isolation member seat assembly of  claim 5 , wherein the at least one gripping component comprises a plurality of gripping components, each angularly spaced from the others about an axis of the seat assembly. 
     
     
         12 . The isolation member seat assembly of  claim 11 , wherein each of the plurality of gripping components comprise at least one slip coupled to the body of the seat assembly and movable from a retracted position to a deployed position to engage and grip the well casing and to thereby secure the seat assembly in the targeted position in the well casing. 
     
     
         13 . The isolation member seat assembly of  claim 12 , wherein each of the plurality of gripping components further comprises a displacement member movable coupled to the body of the seat assembly adjacent to each of the at least one slips of each gripping component, each displacement member movable from a run-in position to an engaged position to displace the at least one slip from the retracted position to a deployed position to engage and grip the well casing. 
     
     
         14 . A method of retrieving a seat assembly from a secured position in a well casing, comprising:
 providing one or more explosive charges coupled to the seat assembly;   securing the seat assembly in the well casing at a targeted position by moving one or more gripping components coupled to the seat assembly from a retracted position to a deployed position to engage and grip the well casing;   introducing an isolation member into the well casing;   sealably engaging the isolation member with the secured seat assembly to isolate a well first portion above the seat assembly from a well second portion below the seat assembly;   applying a substantial pressure to the well first portion to fracture one or more subsurface geologic formations in fluid communication therewith;   detonating the one or more explosive charges to disable the one or more gripping components; and   retrieving at least a body of the seat assembly from the well casing using a tool.   
     
     
         15 . The method of  claim 14 , wherein the one or more gripping components each comprises a slip coupled to the body of the seat assembly and movable from a retracted position to a deployed position to engage and grip the well casing. 
     
     
         16 . The method of  claim 15 , wherein the one or more gripping components each further comprises a displacement member coupled to the body of the seat assembly and movable from a run-in position to an engaged position to displace the slip from the retracted position to the deployed position. 
     
     
         17 . The method of  claim 14 , wherein the one or more gripping components comprises a plurality of gripping components, each angularly spaced one from the others about an axis of the seat assembly. 
     
     
         18 . The method of  claim 14 , wherein the step of detonating the one or more explosive charges to disable the one or more gripping components comprises:
 providing a pressure sensor, a circuit and a battery each within one of a chamber and a recess in the body of the seat assembly;   connecting the pressure sensor, the battery, the one or more explosive charges and the circuit to enable delivery of an electrical current from the battery to the one or more explosive charges upon detection of a predetermined pressure signal using the pressure sensor;   generating the predetermined pressure signal by applying the substantial pressure to the well first portion;   sensing, with the pressure sensor, the predetermined pressure signal; and   generating an electrical current from the battery to the one or more explosive charges to detonate the one or more explosive charges.   
     
     
         19 . The method of  claim 14 , wherein the step of detonating the one or more explosive charges to disable the one or more gripping components comprises:
 providing one or more conductive leads, each having a first end coupled to at least one of the one or more explosive charges and a second end coupled to one or more contacts provided on the seat assembly;   introducing a tool into the well first portion having one or more contacts thereon for engaging the one or more contacts on the seat assembly;   engaging the one or more contacts on the tool with the one or more contacts on the seat assembly; and   delivering an electrical current to through the one or more contacts on the tool, the one or more contacts on the seat assembly, and the one or more conductive leads of the seat assembly to the one or more explosive charges to detonate the one or more explosive charges and to thereby disable the one or more gripping components.   
     
     
         20 . The method of  claim 19 , wherein the tool comprises one of:
 a wireline unit having an elongate conductive member therein for conducting an electrical current; and   a coiled tubing string having a fluid powered electrical current generator coupled to a distal end of the coiled tubing string.