Rat hole bypass for gravel packing assembly

Abstract

A gravel packing slurry bypass for use between a cross-over and a screen in a gravel packing assembly. The bypass includes a section of tubing connected between the cross-over and screen. A liner is carried on the tubing. A seal is carried on the liner to block slurry flow in an annulus outside the liner. The bypass is sized and positioned to provide a slurry bypass flow path past a rat hole.

1 . A gravel packing slurry bypass, comprising: 
 a section of tubing adapted for connection between a crossover and a screen, and    a section of a substantially tubular member carried on the tubing and forming an annulus between the tubing and the tubular member.    
   
   
       2 . The gravel packing slurry bypass of  claim 1 , further comprising: 
 a seal carried on an outer surface of the section of substantially tubular member.    
   
   
       3 . The gravel packing slurry bypass of  claim 2 , wherein the seal is adapted to restrict flow in an annulus surrounding the substantially tubular member when the seal is positioned in a well casing.  
   
   
       4 . The gravel packing slurry bypass of  claim 1 , wherein the section of substantially tubular member has an outer diameter selected to restrict flow in an annulus surrounding the substantially tubular member when a portion of the section of substantially tubular member is positioned in a well casing.  
   
   
       5 . The gravel packing slurry bypass of  claim 1 , wherein the section of substantially tubular member has a length selected to extend across at least a rat hole area in a borehole.  
   
   
       6 . The gravel packing slurry bypass of  claim 1  wherein the substantially tubular member is slidably carried on the tubing.  
   
   
       7 . The gravel packing slurry bypass of  claim 1 , further comprising a sleeve slidably carried on the tubing and attached to the substantially tubular member.  
   
   
       8 . The gravel packing slurry bypass of  claim 7 , wherein the tubing comprises a plurality of sections of tubing connected together by collars having an outer diameter, the sleeve has an inner diameter less than the collar outer diameter, and the sleeve is slidably carried on the tubing between two collars.  
   
   
       9 . The gravel packing slurry bypass of  claim 1 , wherein the section of substantially tubular member has one or more perforations, further comprising a removable material blocking flow of fluids through the one or more perforations.  
   
   
       10 . Apparatus for flowing gravel packing slurry through borehole irregularities located between an upper cased portion of a borehole and a lower portion of a borehole, comprising: 
 a section of tubing adapted to be coupled between a gravel packing crossover in the cased portion of the borehole and a screen in the lower portion of the borehole, and    a liner carried on the outer surface of the tubing, and forming an annulus between the tubing and liner, the liner having a length selected to extend across the borehole irregularities.    
   
   
       11 . The apparatus of  claim 10 , further comprising: 
 a seal carried on the outer surface of the liner and adapted to block slurry flow through an annulus between the liner and the cased portion of the borehole.    
   
   
       12 . The apparatus of  claim 10 , wherein the liner has an outer diameter selected to restrict flow in an annulus surrounding the liner when a portion of the liner is positioned in a well casing.  
   
   
       13 . The apparatus of  claim 10  wherein the liner is slidably carried on the tubing.  
   
   
       14 . The apparatus of  claim 10 , further comprising a sleeve slidably carried on the tubing and attached to the liner.  
   
   
       15 . The apparatus of  claim 14 , wherein the tubing comprises a plurality of sections of tubing connected together by collars having an outer diameter, the sleeve has an inner diameter less than the collar outer diameter, and the sleeve is slidably carried on the tubing between two collars.  
   
   
       16 . The apparatus of  claim 10 , wherein the liner has one or more perforations, further comprising a removable material blocking flow of fluids through the one or more perforations.  
   
   
       17 . A method for flowing gravel packing slurry through a rat hole area between a gravel packing crossover and a screen in a wellbore, comprising: 
 placing a section of pipe in the rat hole area between a gravel packing crossover and a screen, and    positioning a section of tubular member around the section of pipe, thereby forming a first annulus between the pipe and tubular member and a second annulus between the tubular member and the wellbore.    
   
   
       18 . The method of  claim 17 , further comprising flowing gravel packing slurry through the first annulus.  
   
   
       19 . The method of  claim 17 , further comprising: 
 restricting the flow of slurry through the second annulus.    
   
   
       20 . The method of  claim 19  further comprising restricting the flow of slurry with a seal carried on the section of tubular member.  
   
   
       21 . The method of  claim 20  wherein the wellbore is cased above the rat hole area and the section of tubular member has an upper end, further comprising positioning the seal between the upper end of the tubular member and the cased portion of the wellbore.  
   
   
       22 . The method of  claim 19  further comprising restricting the flow of slurry by selecting an outer diameter of at least a portion of the section of tubular member to form a close fit to a well casing when the section of tubular member is positioned in a well.  
   
   
       23 . The method of  claim 17  wherein the section of tubular member has one or more perforations, further comprising: 
 filling the one or more perforations with a removable material, thereby substantially blocking flow through the perforations, and    removing the removable material.    
   
   
       24 . A method for gravel packing a wellbore that penetrates a subterranean oil or gas reservoir and bypassing a rat hole area of the well during gravel packing, comprising: 
 (a) providing a wellbore in the reservoir;    (b) locating a gravel packing assembly in the wellbore, the assembly comprising a crossover, a length of tubing coupled to the crossover and a screen coupled to the tubing, the tubing extending through the rat hole area;    (c) locating a section of liner over the tubing corresponding to the rat hole area, whereby a first annulus is formed between the tubing and the liner and a second annulus is formed between the liner and the wellbore;    (d) restricting the flow of fluids through the second annulus; and    (d) injecting a fluid slurry containing gravel through the crossover into the first annulus.    
   
   
       25 . The method of  claim 24 , wherein the flow of fluids through the second annulus is restricted by a seal.  
   
   
       26 . The method of  claim 25  wherein the wellbore is cased above the rat hole area and the section of liner has an upper end, further comprising positioning the seal between the upper end of the liner and the cased portion of the wellbore.  
   
   
       27 . The method of  claim 24 , wherein the flow of fluids through the second annulus is restricted by selecting a liner size, relative to wellbore size, so that the flow area in the second annulus is substantially smaller than the flow area in the first annulus.  
   
   
       28 . The method of  claim 27 , wherein the wellbore is cased above the rat hole area, further comprising selecting the outer diameter of a portion of the liner to form a close fit with the casing and positioning the portion of the liner in the casing.  
   
   
       29 . The method of  claim 24  wherein the section of liner has one or more perforations, further comprising: 
 filling the one or more perforations with a removable material, thereby substantially blocking flow through the perforations, and    removing the removable material.    
   
   
       30 . The method of  claim 29 , further comprising flowing produced fluids through the one or more perforations.  
   
   
       31 . A gravel packing assembly, comprising: 
 a crossover,    a length of tubing having a first end connected to the crossover,    a screen connected to a second end of the length of tubing, and    a length of liner carried on the outer surface of the length of tubing.    
   
   
       32 . The gravel packing assembly of  claim 31 , further comprising a seal carried on the outer surface of the liner and adapted for blocking flow of fluid between the liner and a borehole.  
   
   
       33 . The gravel packing assembly of  claim 31 , wherein the liner has an outer diameter adapted for blocking flow of fluid between the liner and a borehole.  
   
   
       34 . The gravel packing assembly of  claim 31 , wherein the liner has one or more perforations, further comprising a removable material blocking flow of fluids through the one or more perforations.  
   
   
       35 . Apparatus for flowing gravel packing slurry through borehole irregularities located between an upper cased portion of a borehole and a lower portion of a borehole, comprising: 
 a section of tubing adapted to be coupled between a gravel packing crossover in the cased portion of the borehole and a screen in the lower portion of the borehole, the tubing forming an annulus between the tubing and the borehole,    one or more conduits carried on the outer surface of the tubing and in the annulus, the conduits having a length selected to extend across the borehole irregularities, and    a seal for restricting flow in the annulus outside the conduits.    
   
   
       36 . Apparatus according to  claim 35  wherein the seal comprises an elastomeric seal substantially filling the annulus outside the one or more conduits.  
   
   
       37 . Apparatus according to  claim 36  wherein the elastomeric seal has an outer diameter selected to seal against a well casing.  
   
   
       38 . Apparatus according to  claim 35  wherein the one or more conduits comprises a section of a substantially tubular member carried substantially coaxially around the section of tubing.  
   
   
       39 . Apparatus according to  claim 38  wherein the section of a substantially tubular member has an outer diameter selected to form a close fit to a well casing, the close fit forming the seal for restricting flow in the annulus outside the one or more conduits.  
   
   
       40 . A method for gravel packing a well having a cased upper portion, a rat hole area below the cased upper portion and a producing zone below the rat hole area, comprising: 
 positioning a sand screen in the producing zone,    positioning a tubing in the well extending through at least a portion of the cased upper portion and the rat hole area and to the sand screen, the tubing defining an annulus between the tubing and the well,    positioning one or more conduits in the annulus extending across the rat hole area, and    flowing gravel packing slurry from the surface to the producing zone comprising flowing substantially all of the gravel packing slurry through the one or more conduits.    
   
   
       41 . A method according to  claim 40 , further comprising restricting flow of fluids in the annulus outside the one or more conduits.  
   
   
       42 . A method according to  claim 41 , further comprising positioning a seal in the annulus outside the one or more conduits.