The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 16, 1999
Filed:
Sep. 05, 1997
George A Gillespie, Coon Rapids, MN (US);
Stephen A Uban, Stillwater, MN (US);
Abstract
Well casing assembly for use in oil and gas wells, and especially deviated or horizontal wells, has an inner pipe member with threaded ends which permit a number of casing assemblies to be joined in a string. The inner pipe has a series of perforations along a segment of its length which are covered by an elongated screen member which prevents the passage of sand particles. A concentric outer protective cover member is devoid of perforations in regions which are radially opposite the inner screen to prevent damage to the screen. One or more perforated segments of the outer member are axially spaced from the screen member so that inward flow from a formation will have its energy and velocity reduced before it reaches the screen, thereby minimizing erosion of the screen surface. If desired, perforated flow control devices such as annular rings can be located between the inner pipe and outer member at the ends of the screen segment to allow a more uniform flow to the screen, and thus further reduce erosion.