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. 29, 1978
Filed:
Feb. 24, 1977
Fusao Koshiga, Kawasaki, JP;
Jinkichi Tanaka, Yokohama, JP;
Itaru Watanabe, Yokohama, JP;
Motoaki Suzuki, Yokohama, JP;
Toshifumi Kojima, Yokohama, JP;
Hiroyoshi Matsubara, Fukuyama, JP;
Tatsumi Osuka, Fukuyama, JP;
Kenji Takeshige, Fukuyama, JP;
Takashi Nagamine, Fukuyama, JP;
Osamu Hirano, Fukuyama, JP;
Nippon Kokan Kabushiki Kaisha, Tokyo, JP;
Abstract
In longitudinally seam-welding a pipe-blank for welded steel pipe from the inside along a groove by the reverse-polarity GMA welding process comprising using direct electric current supplied to a consumable electrode through a cable as the welding current with said consumable electrode as the anode, the direction of said direct electric current for welding flowing through said cable introduced into said pipe-blank is set in the same direction as that of welding, thereby preventing occurrence of a magnetic arc blow of the welding arc from said consumable electrode toward the upstream side of the welding direction, i.e., in the opposite direction to that of welding.