Pressure Insensitive Counting Toe Sleeve

Abstract

A downhole tool has a housing with a communication path extending from a first to a second part of a bore. An indexer disposed in the communication path is movably responsive to applied pressure at the first part. The indexer counts a number of applications of the applied pressure and permits fluid communication of the applied pressure from the first part to the second part in response to the counted number. An insert in the housing bore sealably encloses the second part of the communication path and is movable from a first position covering to a second position uncovering a port in the housing. At least a portion of the insert acted upon by the applied fluid pressure in the second part initiates movement of the insert from the first to the second position. A kit having a modular housing portion and the indexer can adapt the downhole tool for use.

What is claimed is: 
     
         1 . A method of opening a sleeve disposed on a tubing string in a wellbore, the method comprising:
 holding an insert temporarily toward a closed condition relative to at least one port in the sleeve using at least one retainer;   counting, with a counter of the sleeve, a plurality of applications of fluid pressure in the tubing string;   permitting, in response to the counted applications, communication of the fluid pressure from a first part of a communication path of the sleeve to act on a portion of the insert in a second part of the communication path of the sleeve;   releasing the hold of the at least one retainer on the insert in response to the communication permitted to act on at least the portion of the insert; and   shifting the insert toward an opened condition relative to the at least one port in the sleeve in response to the released hold.   
     
     
         2 . The method of  claim 1 , wherein holding the insert toward the closed condition in the sleeve using the at least one retainer comprises holding the insert using at least one shear element disposed between the insert and a housing of the sleeve, the shear element being configured to shear in response to a predetermined shear force. 
     
     
         3 . The method of  claim 1 , wherein releasing the hold of the at least one retainer in response to the communication comprises breaking the at least one retainer in response to a level of the fluid pressure permitted to act against the portion of the insert. 
     
     
         4 . The method of  claim 1 , further comprising locking the insert in the opened condition with a lock engageable within the sleeve. 
     
     
         5 . The method of  claim 1 , wherein holding the insert temporarily toward the closed condition relative to the at least one port in the sleeve using the at least one retainer comprises sealing first and second seals on the insert against a bore of the sleeve on both sides of the at least one port. 
     
     
         6 . The method of  claim 1 , wherein counting, with the counter of the sleeve, the plurality of applications of the fluid pressure in the tubing string comprises responding, with the counter of the sleeve, to increasing and decreasing of the fluid pressure applied down the tubing string in the plurality of applications. 
     
     
         7 . The method of  claim 1 , wherein shifting the insert toward the opened condition relative to the at least one port in the sleeve comprises shifting the insert by collapsing a pressure chamber sealed between the insert and the sleeve. 
     
     
         8 . The method of  claim 1 , wherein counting, with the counter of the sleeve, the plurality of applications of the fluid pressure comprises initially breaching, in response to a level of the fluid pressure in a bore of the sleeve, a barrier disposed between the bore and the first part of the communication path. 
     
     
         9 . The method of  claim 1 , wherein counting, with the counter of the sleeve, the plurality of applications of the fluid pressure comprises moving a piston of the counter in the first part of the communication path with the applications of the fluid pressure. 
     
     
         10 . The method of  claim 9 , wherein permitting, in response to the counted applications, the communication of the fluid pressure from the first part to the second part of the communication path comprises moving a seal of the counter, initially in a sealed condition, to an unsealed condition in response to the movement of the piston, the unsealed condition permitting the communication past the seal of the counter and into the second part of the communication path. 
     
     
         11 . The method of  claim 10 , wherein counting the plurality of applications of the fluid pressure at the first part of the communication path against the piston comprises:
 biasing a ring of the piston against the applications of the fluid pressure; and   moving the ring, responsive to the applications of the fluid pressure at the first part of the communication path, between first and second positions in the first part of the communication path of the sleeve.   
     
     
         12 . The method of  claim 11 , wherein moving the seal of the counter comprises moving at least one rod with the ring between first and second of the sealed condition, the at least one rod in the first and second sealed conditions preventing communication of the fluid pressure from the first part to the second part of the communication path. 
     
     
         13 . The method of  claim 12 , wherein moving the seal of the counter comprises moving, in response to the counted applications, the at least one rod to the unsealed condition permitting the communication of the fluid pressure from the first part to the second part. 
     
     
         14 . The method of  claim 12 , wherein moving the ring, responsive to the applications of the fluid pressure at the first part of the communication path, between the first and second positions comprises controlling, in response to each of the applications of the fluid pressure, the movement of the ring with a slot and pin arrangement. 
     
     
         15 . The method of  claim 1 , comprising initially configuring the sleeve from a downhole tool that has a housing with a first housing portion coupleable to a second housing portion, the housing defining a housing bore therethrough and defining the at least one port communicating the housing bore outside the housing, the downhole tool having the insert movably disposed in the housing bore, by coupling an intermediate housing portion in series between the first and second housing portions, the intermediate housing portion having the counter and having a first end coupling to the first housing portion to define the first part of the communication path, the intermediate housing portion having a second end coupling to the second housing portion to define the second part of the communication path. 
     
     
         16 . The method of  claim 15 , wherein the insert is disposed in the second housing portion, and wherein the portion of the insert at least partially encloses the second part of the communication path defined by the intermediate housing portion coupled with the second end of the second housing portion. 
     
     
         17 . The tool of  claim 16 , wherein the first and second housing portions are configured to couple together without the intermediate housing portion and the counter to form the downhole tool. 
     
     
         18 . A method of opening fluid communication between a tubing string and an annulus in a wellbore, the method comprising:
 configuring a toe sleeve to open from a closed condition to an opened condition in response to a plurality of applications of fluid pressure in the tubing string;   deploying the configured toe sleeve and one or more second sleeves on the tubing string in the wellbore, the configured toe sleeve disposed toward the toe, the one or more second sleeves disposed uphole of the toe sleeve;   breaching a burst disc on the configured toe sleeve by applying a first of the applications of the fluid pressure down the tubing string; and   opening the configured toe sleeve from the closed condition to the open condition by applying remaining ones of the applications of the fluid pressure down the tubing string, counting each of the remaining ones of the applications of the fluid pressure, releasing a seal in response to the counted applications, and permitting the fluid pressure to open an insert of the configured toe sleeve in response to the released seal.   
     
     
         19 . The method of  claim 18 , wherein breaching the burst disc on the configured toe sleeve by applying the first of the applications of the fluid pressure down the tubing string comprises applying the first application of the fluid pressure at a first level configured to burst the burst disc; and wherein opening the configured toe sleeve from the closed condition to the open condition by applying the remaining ones of the applications of the fluid pressure down the tubing string comprises applying the remaining ones of the applications at a second level to move a counter disposed in the toe sleeve. 
     
     
         20 . A method of opening fluid communication between a tubing string and an annulus in a wellbore, the method comprising:
 providing a downhole tool having an insert configured to open in response to one application of fluid pressure at a level breaching a burst disc on the downhole tool, the downhole tool having first and second housing portions connected together;   configuring the downhole tool to open the insert for one or more additional applications of the fluid pressure by installing an intermediate housing portion, having a counter configured to count the one or more additional applications, in series between the first and second housing portions;   deploying the configured downhole tool on the tubing string in the wellbore; and   opening the insert of the downhole tool for fluid communication between the tubing string and the annulus by applying the one application of the fluid pressure at the level breaching the burst disc followed by applying the one or more additional applications of the fluid pressure for the counter to count.