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. 12, 2002
Filed:
Mar. 09, 2000
Robert A. R. Mills, Bragg Creek, CA;
Kudu Industries, Inc., , CA;
Abstract
A hardfacing for downhole progressing cavity pumps is disclosed as well as a method for producing same. The hardfacing consists of a ceramic layer applied to a ferrous pump rotor body by way of plasma spraying and a top layer of metallic material having a lower hardness than the ceramic. The ceramic layer has a grainy surface with a plurality of peaks and intermediate depressions, the peaks being formed by ceramic grains at the surface of the ceramic layer. The thickness of the top layer is adjusted such that the depressions between the peaks of the ceramic layer are completely filled thereby providing the rotor with a ceramic hardfacing of significantly reduced surface roughness. In the process of the invention, the pump rotor, which may be provided with a molybdenum bonding layer, is plasma coated with the ceramic and the resulting ceramic layer is covered with the metallic material top layer. The top layer is polished either until the dimensions thereof are within the tolerances acceptable for the finished rotor or until a majority of the peaks of the ceramic layer are exposed.