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:
Jun. 14, 2016
Filed:
Apr. 28, 2011
Koji Yano, Chiba, JP;
Hiroyuki Sumi, Chiba, JP;
Kenji Oi, Chiba, JP;
JFE STEEL CORPORATION, Tokyo, JP;
Abstract
A method of manufacturing a laser welded steel pipe by forming a steel strip into a cylindrical open pipe and performing laser welding on edges that includes: emitting two laser beams along the edges from an upper surface side of the open pipe, the two laser beams being transmitted through different optical fibers with in-focus spot diameters exceeding 0.3 mm; emitting leading and trailing laser beams each inclined toward a direction in which welding proceeds at an incident angle with respect to a direction perpendicular to an upper surface of the open pipe; setting the incident angle of the leading laser beam to be larger than the incident angle of the trailing laser beam; and setting a gap between a center point of the leading laser beam and a center point of the trailing laser beam on a back surface of the open pipe to 1 mm or larger.