DRAINAGE OR FILTER LAYER FOR WELL SCREEN ASSEMBLY WITH INTEGRATED STAND-OFF STRUCTURE

摘要

An integral structure including woven wire cloth or non-woven metal filter medium for use as a drainage layer (31) or filter layer (37) in a well screen assembly is provided. A plurality of elongated members (32) are welded on the woven metal cloth (31) or non- woven metal filter medium to provide reduced resistance to flow parallel to a layer of the woven cloth. Segments (A, B, C) of the woven or non- woven metal materials having elongated members (71, 74) joined thereto may be rolled into a cylinder to form a part of a well screen assembly.