Patent ID: 7735553

Claim:
A prepacked screen assembly, comprising: a tubular well casing member having an outer cylindrical surface with a first groove formed therein; a first bushing having an inner bore with a raised lip for engaging said first groove to prevent axial movement of said first bushing, said raised lip being flexible in a radially outward direction during assembly to permit the first bushing to slide over the tubular well casing member until the raised lip engages said first groove; a second groove formed in the outer cylindrical surface of the tubular well casing member at a location axially spaced from said first groove; a second bushing having an inner bore with a raised lip for engaging said second groove to prevent axial movement of said second bushing, said raised lip of said second bushing being flexible in a radially outward direction during assembly to permit the second bushing to slide over the tubular well casing member until the raised lip engages said second groove; wherein said first and second bushings each comprises an outer surface, and further comprising a cylindrical-shaped mesh screen member concentrically positioned around said well casing member with a first end of the mesh screen member secured over the outer surface of said first bushing and a second end of the mesh screen member secured over the outer surface of said second bushing, and a filter pack of granular material surrounding the well casing member and contained within an area defined by the outer cylindrical surface of the well casing member, an inner surface of the screen member, and the first and second bushings; and further comprising first and second clamps for securing the mesh screen member to the outer surfaces of the first and second bushing members, respectively.