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:
Sep. 11, 1984
Filed:
Aug. 31, 1982
Richard L Holbrook, Louisville, OH (US);
Dean L Mayer, Alliance, OH (US);
The Babcock & Wilcox Company, New Orleans, LA (US);
Abstract
A method of prestressing a tubular apparatus having coaxial inner and outer tubes which are connected to each other at axially spaced locations comprises, after the inner and outer walls are connected to each other and the tube is heat-treated or otherwise processed, reducing the diameter of the outer wall so that the outer wall is elongated. The elongation of the outer wall establishes a prestressed condition between the inner and outer walls, with the inner wall under tension and the outer wall under compression. The reduction in diameter of the outer wall can be accomplished by using a roll extrusion machine, a tube reducer or a draw bench.