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. 29, 2019
Filed:
Mar. 23, 2016
Nakagawa Sangyo Co., Ltd., Inuyama-shi, JP;
Noriaki Nakagawa, Inuyama, JP;
NAKAGAWA SANGYO CO., LTD., Inuyama-Shi, JP;
Abstract
A method for manufacturing a double pipe includes: drawing a plate (), which has a predetermined shape corresponding to the desired final shape of a curved outer pipe (), into a curved, substantially U-shape in cross-section to produce a half pipe (). Then, an inner pipe (), which has a curved shape similar to the desired final curved shape of the outer pipe, is inserted into and positioned within the interior space of the half pipe. Subsequently, the inner pipe is welded to the half pipe at one longitudinal end thereof. Thereafter, longitudinally-extending edges of the half pipe are curled towards each other until they abut and a substantially circular cross-section is formed that surrounds the exterior of the inner pipe. The abutting longitudinally-extending edges () of the half pipe are then welded together to produce the curved outer pipe ().