Configuring a velocity string in a production tubing of a wet gas production well

Abstract

A velocity string for increasing fluid velocity in a production tubing (1) of a wet natural gas production well is configured downhole by:—inserting components (5) for configuring an annular liner (4) into the production tubing (1); and—clustering the components together in an annular space (9) adjacent to an inner surface of the production tubing (1) to configure the annular liner (4) in a cost effective manner without requiring killing the well with a high density liquid, expensive hoisting and/or other workover equipment and materials required to install conventional corrosion resistant steel velocity strings.

1 . A method for producing wet natural gas comprising downhole configuring a velocity string to increase fluid velocity in a production tubing of a wet natural gas production well, the method comprising:
 inserting components for configuring an annular liner into the production tubing;   clustering the components together in an annular space within the production tubing to configure the annular liner; and   producing wet natural gas through the interior of the velocity string formed by the annular liner.   
     
     
         2 . The method of  claim 1 , wherein the components are injected in a substantially liquid form into the well and are solidified and/or bonded together in the annular space to configure the annular liner. 
     
     
         3 . The method of  claim 2 , wherein the liquid components are inserted by pumping the liquid components into the annular space and the annular liner is formed by inducing the liquid components to harden in the annular space within the production tubing. 
     
     
         4 . The method of  claim 2 , wherein lowering a slug line through the production tubing and subsequently retrieving the slug line from the production tubing while pumping slugs of said components down the slug line to a frusto-conical injection head at a lower end of the slug line, wherein the components are mixed at an entrance of the frusto-conical injection head, and discharging mixed components against the inner surface of the production tubing, whereby allowing the mixed components to cure to generate a cured solidified annular liner against the inner surface of the production tubing. 
     
     
         5 . The method of  claim 4 , wherein the components are gels. 
     
     
         6 . The method of  claim 3 , wherein:
 the liquid components are inserted by injecting them as an annular gel body around a substantially cylindrical core formed by a degradable gel which is injected into the wellhead simultaneously with and at substantially the same downward velocity as the annular gel body, and   after the annular space is substantially filled with the annular gel body the annular gel body is allowed to harden and the cylindrical core is allowed to degrade.   
     
     
         7 . The method of  claim 3 , wherein the liquid components are inserted by:
 inserting a casting string through a stuffing box at a wellhead of the well, which casting string is provided near a lower end thereof with one of the group consisting of a solid bottom plug and an annular bottom plug, which bottom plug slideably engages an inner surface of the production tubing; and   pumping the liquid filler material through an injection port in the wellhead below the stuffing box and above the bottom plug, thereby pushing the bottom plug down into the well until it has reached a target depth.   
     
     
         8 . The method of  claim 7 , wherein the casting string comprises one of the group consisting of a solid rod and a tubular, which is removed from the well before the step of producing wet natural gas through the interior of the annular liner. 
     
     
         9 . The method of  claim 7 , wherein:
 the casting string is an expandable casting tubular;   during the pump down procedure the casting tubular is collapsed by the pressure of the liquid filler material that is pumped into the surrounding annular space; and   after the bottom plug has reached the target depth fluid is pumped into the interior of the casting tubular, thereby radially expanding the tubular and pushing excess liquid filler slurry out of the annular space via the injection port.   
     
     
         10 . The method of  claim 7 , wherein:
 the casting string is a casting tubular with a bottom section having a larger outer diameter than an upper part of the casting tubular;   the liquid filler material comprises a chemical composition that hardens upon mixing with a hardening agent;   after the bottom plug has reached the target depth the casting tubular is pulled out of the well, whilst the interior of the bottom section thereof is closed and the hardening agent is injected via the upper part of the casting tubular and a hardening agent injection opening in the wall of the casting tubular above the closed bottom section, thereby generating a hardened synthetic liner.   
     
     
         11 . The method of  claim 7 , wherein:
 the casting string is one of the group consisting of a rod and a tubular, made of poly-ethylene or another plastic material that stretches and obtains a reduced diameter when a tension force is exerted to the casting string; and   the casting string is released from the bottom plug and pulled out of the well after hardening of the annular liner.   
     
     
         12 . The method of  claim 2 , wherein the liquid components are inserted by a longitudinally movable, and optionally rotatable, spray head that sprays and clads the liquid components against the inner surface of the production tubing to configure the annular liner. 
     
     
         13 . The method of  claim 2 , wherein the liquid components comprise a cement slurry, which is induced to harden to an annular cement liner. 
     
     
         14 . The method of  claim 2 , wherein the liquid components comprise a fluid resin which hardens downhole to an annular synthetic liner. 
     
     
         15 . The method of  claim 14 , wherein the liquid components comprise a hardenable resin composition and a hardening agent that are separately injected into the well and mixed and cured downhole. 
     
     
         16 . The method of  claim 1 , wherein the components comprise ring shaped liner sections with substantially cylindrical inner surfaces that are clustered together by stacking the sections on top of each other within the annular space to configure the annular liner. 
     
     
         17 . The method of  claim 1 , wherein the components and any associated casting and/or other annular liner assembling equipment are inserted via at least one of the group consisting of a pressure resistant lock, a lubricator, and a stuffing box in the wellhead, and wherein the well is not killed by a high density liquid when the annular liner is configured. 
     
     
         18 . The method of  claim 1 , wherein producing wet natural gas through the interior of the production tubing prior to inserting the components for configuring the annular liner into the production tubing. 
     
     
         19 . The method of  claim 1 , wherein, after having produced wet natural gas through the interior of the velocity string formed by the annular liner for a period of time, inserting and clustering additional components for configuring an additional annular liner within the annular liner. 
     
     
         20 . A method of downhole configuring a velocity string to increase fluid velocity in a production tubing of a wet natural gas production well, the method comprising:
 inserting components for configuring an annular liner into the production tubing;   clustering the components together in an annular space within the production tubing to configure the annular liner.