Performing a wellbore tieback operation

Abstract

A wellbore tieback system that includes a liner, a tieback string, and a seal system. The liner is disposed within a wellbore and defines an annulus between an external surface of the liner and a wall of the wellbore. The tieback string has a receptacle end that defines an inner diameter larger than an outer diameter of the liner such that the receptacle end can be disposed within the annulus to receive a portion of the liner. The seal system is coupled to an internal surface of the receptacle end. The seal system has at last one annular seal that swells inwardly to form, with the portion of the liner inserted within the receptacle end, a seal with the external surface of the liner. The tieback string is fluidly coupled, with the seal formed, to the liner to receive production fluid from the liner.

What is claimed is: 
     
         1 . A wellbore tieback system, comprising:
 a liner disposed within a wellbore, the liner set on the wellbore and defining an annulus between an external surface of the liner and a wall of the wellbore;   a tieback string configured to be disposed within the wellbore, the tieback string comprising a receptacle end defining an inner diameter larger than an outer diameter of the liner such that the receptacle end is configured to be disposed within the annulus to receive a portion of the liner; and   a seal system coupled to an internal surface of the receptacle end, the seal system comprising at last one annular seal configured to swell inwardly to form, with the portion of the liner inserted within the receptacle end, a seal with the external surface of the liner, the tieback string fluidly coupled, with the seal formed, to the liner to receive production fluid from the liner.   
     
     
         2 . The wellbore tieback system of  claim 1 , wherein the tieback string comprises a tubular body extending from or near a terranean surface of the wellbore to the receptacle end, the tubular body defining an inner diameter substantially equal to or greater than an inner diameter of the liner. 
     
     
         3 . The wellbore tieback system of  claim 1 , wherein the at least one annular seal comprises at least one swellable seal configured to swell upon exposure to a wellbore fluid to form the seal. 
     
     
         4 . The wellbore tieback system of  claim 3 , wherein the wellbore fluid is at a temperature of between 150 and 350 degrees Fahrenheit when the fluid touches the at least one swellable seal. 
     
     
         5 . The wellbore tieback system of  claim 3 , wherein the at least one swellable seal comprise an elastomer configured to absorb fluid to swell over a time period of 3 to 5 days to form the seal. 
     
     
         6 . The wellbore tieback system of  claim 3 , wherein the at least one swellable seal is configured to swell absent mechanical movements of the tieback string and absent fluid pumped downhole through the tieback string. 
     
     
         7 . The wellbore tieback system of  claim 1 , wherein the liner is partially cemented in the wellbore, the annulus extending from an uphole inlet of the liner to a liner hanger or cement disposed between the liner and a wall of the wellbore. 
     
     
         8 . The wellbore tieback system of  claim 1 , wherein the liner comprises a monobore completion liner, and the portion of the liner comprises an uphole fluid inlet formed upon cutting the liner and retrieving a second portion of the liner uphole of the portion of the liner. 
     
     
         9 . A wellbore assembly, comprising:
 a casing pipe configured to be disposed within a wellbore, the casing pipe defining, with the casing pipe set on the wellbore, an annulus between an external surface of the casing pipe and a wall of the wellbore; and   a wellbore string configured to be disposed within the wellbore, the wellbore string comprising a downhole end defining an inner diameter larger than an outer diameter of an uphole end of the casing pipe, the downhole end comprising at least one internal, annular seal configured to expand to form, with the uphole end of the casing pipe inserted within the downhole end of the wellbore string, a seal with the external surface of the casing pipe, the wellbore string fluidly coupled, with the seal formed, to the casing pipe to flow fluid between the wellbore string and the casing pipe.   
     
     
         10 . The wellbore assembly of  claim 9 , wherein the wellbore string comprises a tubular body extending from or near a terranean surface of the wellbore to the downhole end, the tubular body defining an inner diameter equal to or greater than an inner diameter of the casing pipe. 
     
     
         11 . The wellbore assembly of  claim 9 , wherein the at least one annular seal comprises at least one swellable seal configured to swell upon exposure to a wellbore fluid to form the seal 
     
     
         12 . The wellbore assembly of  claim 11 , wherein the wellbore fluid is at a temperature of between 150 and 350 degrees Fahrenheit when the fluid touches the at least one swellable seal. 
     
     
         13 . The wellbore assembly of  claim 11 , wherein the at least one swellable seal comprises an elastomer configured to absorb fluid to swell over a period of time and form a seal with an unpolished or uneven surface of the casing pipe. 
     
     
         14 . The wellbore assembly of  claim 11 , wherein each swellable seal is disposed within a respective internal groove of the downhole end, each swellable seal comprising a compliant external surface configured to swell from the groove toward the external surface of the casing pipe. 
     
     
         15 . The wellbore assembly of  claim 9 , wherein the casing pipe is partially cemented in the wellbore, the annulus extending from an uphole inlet of the casing pipe to a casing pipe hanger or packer or cement disposed between the casing pipe and a wall of the wellbore. 
     
     
         16 . The wellbore assembly of  claim 9 , wherein the seal fluidly isolates the annulus from a bore of the wellbore string and a bore of the casing pipe. 
     
     
         17 . The wellbore assembly of  claim 9 , wherein the casing pipe comprises a monobore completion casing pipe, and the portion of the casing pipe comprises an uphole fluid inlet formed upon cutting the casing pipe and retrieving a second portion of the casing pipe uphole of the portion of the casing pipe. 
     
     
         18 . A method, comprising:
 running a tieback string within a wellbore comprising a liner defining an annulus between an external surface of the liner and a wall of the wellbore, the tieback string comprising a receptacle end comprising an inner diameter larger than an outer diameter of the liner, the receptacle end comprising at least one annular seal configured to swell inwardly to form, with the portion of the liner inserted within the receptacle end, a seal with the external surface of the liner;   positioning the receptacle end around a portion of the liner; and   activating the at least one annular seal to form, with the external surface of the liner, a seal, the tieback string fluidly coupled, with the seal formed, to the liner to receive production fluid from the liner.   
     
     
         19 . The method of  claim 18 , further comprising, before running the tieback string within the wellbore, cutting the liner and retrieving an upper portion of the liner to form the portion of the liner. 
     
     
         20 . The method of  claim 18 , wherein activating the annular seal comprises flowing, from a terranean surface of the wellbore and through the tieback string, a fluid configured to reach the at least one annular seal at a temperature of between 150 and 350 degrees Fahrenheit.