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:
Jan. 11, 2000
Filed:
Oct. 20, 1997
Philip N Hulsizer, Atlanta, GA (US);
Welding Services, Inc., Norcross, GA (US);
Abstract
A method is disclosed for applying a weld overlay to a tube. Using a first weld head, a bead of overlay material is applied onto a tube by melting the overlay material. In the process of applying the weld bead to the tube, a heat affected zone is created within the tube. Thereafter, a second weld head is employed to apply sufficient heat to the exterior of the tube to raise the temperature within the heat-affected zone to a temperature higher than its tempering temperature but lower than its Ae1 temperature. In this manner the heat affected zone is eliminated without creating a new heat affected zone in the process. In the disclosed embodiment, the tube is rotated with respect to the weld heads, while the weld heads move along the longitudinal axis of the tube. According to the disclosed embodiment, the first weld head employs a gas-metal arc welding process, and the second weld head employs a gas-tungsten arc welding process.