Filter Media For Sand Control Screen Assemblies

Abstract

A sand control screen assembly having a filter medium that provides a controlled offset between a shroud and the filter medium, and/or between a base pipe and the filter medium. The sand control screen assembly may also include a drainage layer positioned about the base pipe. The sand control screen assembly is utilized for preventing the flow of particulate material of a predetermined size therethrough and allowing the flow of production fluids therethrough.

What is claimed is: 
     
         1 . A sand control screen assembly, comprising:
 a base pipe having openings through a thickness of the pipe;   a filter medium disposed about the base pipe; and   a radial extension for ensuring substantially uniform radial spacing relative to at least one of the filter medium's inner surface and outer surface.   
     
     
         2 . The sand control screen assembly of  claim 1 , wherein the radial extension comprises a wire assembly adjacent the inner or outer surface of the filter medium. 
     
     
         3 . The sand control screen assembly of  claim 1 , wherein the radial extension comprises a metal sheet strips 
     
     
         4 . The sand control screen assembly of  claim 3 , wherein the metal sheet strips are assembled in sections along at least one of the filter medium's inner surface and outer surface. 
     
     
         5 . The sand control screen assembly of  claim 1 , wherein the radial extension is coupled to the filter medium. 
     
     
         6 . The sand control screen assembly of  claim 1 , further comprising a shroud disposed about the filter medium for protecting the filter medium. 
     
     
         7 . The sand control screen assembly of  claim 6 , wherein the radial extension is disposed between the shroud and the filter medium. 
     
     
         8 . The sand control screen assembly of  claim 1 , further comprising a drainage layer disposed between the base pipe and the filter medium. 
     
     
         9 . The sand control screen assembly of  claim 8 , wherein the radial extension is disposed between the drainage layer and the filter medium. 
     
     
         10 . The sand control screen assembly of  claim 1 , wherein the radial spacing is in the range of from about 0.05 to about 1.0 inch. 
     
     
         11 . A sand control screen assembly, comprising:
 a perforated base pipe;   a filter medium disposed about the base pipe; and   an offset means for providing a radial spacing relative to at least one of the filter medium's inner surface and outer surface.   
     
     
         12 . The sand control screen assembly of  claim 11 , wherein the offset means is oriented helically, longitudinally, or circumferentially about the filter medium's outer surface. 
     
     
         13 . The sand control screen assembly of  claim 11 , wherein the offset means is oriented helically, longitudinally, or circumferentially along the filter medium's inner surface. 
     
     
         14 . The sand control screen assembly of  claim 11 , wherein the offset means is assembled in sections along at least one of the filter medium's inner surface and outer surface. 
     
     
         15 . The sand control screen assembly of  claim 11 , wherein the offset means comprises metal sheet strips. 
     
     
         16 . The sand control screen assembly of  claim 11 , further comprising a shroud disposed about the filter medium for protecting the filter medium. 
     
     
         17 . The sand control screen assembly of  claim 11 , further comprising a drainage layer disposed between the base pipe and the filter medium. 
     
     
         18 . The sand control screen assembly of  claim 11 , wherein the radial spacing is in the range of from about 0.05 to about 1.0 inch.