A well screen for placement within wells used to filter out impurities from the fluid entering the well. In the preferred embodiment, the well screen comprises a spirally-wound wire forming a cylinder with gaps between the layers of wire. The layers of wire are attached by spacers placed within the gaps. In an alternative embodiment, the well screen is formed from concentric rings, and in a third embodiment the well screen is formed from a cylindrical tubes that are machined to remove material to form horizontal gaps. In the first two embodiments, at least one spacer is integrally formed to the wire or a ring to minimize the amount of welding required to secure the spacers to adjacent rings or windings.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of application Ser. No. 09/123,197 filed on Jul. 27, 1998, now U.S. Pat. No. 6,089,316, which is a continuation-in-part of application Ser. No. 08/904,883 filed on Aug. 1, 1997, now U.S. Pat. No. 5,785,122.
An apparatus for manufacturing a wire wound filter screen from wrapping wrap wire over a set of rib wires has a frame, a spindle for supporting the rib wires in a longitudinal orientation, a wire guide for delivering wrap wire around the rib wires as the spindle rotates the rib wires, an electrode for welding the wrap wires to the rib wires at each intersection thereof, and a translating mechanism positioned on the frame for moving rib wires and the welded wrap wire longitudinal along the frame. A laser measures a gap between adjacent surfaces of wrap wire. A processor is used to adjust the translating of the rib wires relative to the gap. An air cushion urges the electrode against the wrap wire.
The system and method of the present invention includes an electrical to mechanical converter (EMC), such as a motor, and a hydraulic pump-and-cylinder arrangement that is connected to the electrical to mechanical converter for input, and to a sucker rod pump for output, in at least one embodiment. The entire assembly can be deployed below the level of the well fluid in a well. The EMC-driven hydraulic pump and cylinder can provide reciprocating linear motion to operate the sucker rod pump. In contrast, this linear motion is normally provided by sucker rods connected to a plunger inside a pump barrel and a pumping unit on the surface. The invention provides the required linear motion for the sucker rod pump to operate, but without the need for sucker and a surface pumping unit.
