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:
Aug. 08, 1989
Filed:
Jun. 19, 1987
Dean L Mayer, Fremont, IN (US);
The Babcock & Wilcox Company, New Orleans, LA (US);
Abstract
Formation of continuous grooves on the internal surface of a tube shell, in a single continuous cold drawing step, in which the tube shell is first sunk in a die over a reduced diameter cylindrical mandrel portion so that the diameter of the inner surface of the tube shell is reduced to a dimension below the base of the grooves of a grooved plug portion of the mandrel thereby retarding longitudinal movement of a portion of the reduced internal surface of the sunk tube shell at a plurality of circumferentially spaced intervals to effect formation of longitudinally continuous shallow grooves. The mandrel is allowed to rotate if it is desirable to facilitate the formation of spiral grooves on the tube inner surface.