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:
Jul. 04, 1989
Filed:
Dec. 18, 1987
Wallace C Rudd, New Canaan, CT (US);
Humfrey N Udall, Darien, CT (US);
Robert R Harriau, Old Greenwich, CT (US);
Thermatool Corporation, Stamford, CT (US);
Abstract
Method and apparatus for butt welding the edge faces of metal skelp which has been heated to a temperature of at least 1000.degree. F. but below the welding temperature of the metal of the skelp. The skelp is continuously advanced through a furnace in which the skelp is heated to such temperature and then, to forming rolls where the skelp is formed into a substantially complete tube with closely spaced skelp edge faces, to a spacing roll for maintaining the edge faces in closely-spaced relation and to pressure rolls where the edge faces are pressed together. Intermediate the spacing roll and the pressure rolls, the edge faces are heated to welding temperature with an induction coil fed with electrical current having a frequency of at least 10 Khz. The induction coil does not encircle the skelp in its tubular forms and instead, has legs adjacent the edge faces and at opposite sides of the gap between the edge faces.