摘要 |
Improved well screen has its open area defined by a helically wrapped strip of wire mesh which is supported by a rigid cage-like structure of welded steel longitudinal support rods and helical wrap wires. The design is cost competitive with the simple, and rather fragile, screens made by wrapping a mesh about a perforated pipe while offering the mechanical strength characteristics of wire-wrapped welded screens and a substantially larger open area for flow. The wire mesh strip is helically wound with a gap and at least one wrap wire is helically wound in the gap so that a small portion of its width can be firmly adhered to the rods while at least another portion of its width overlies an adjacent side edge of the mesh strip. |