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:
Oct. 15, 2019
Filed:
Mar. 28, 2017
Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;
Satoshi Hirose, Tokyo, JP;
NIPPON STEEL CORPORATION, Tokyo, JP;
Abstract
A metal pipe has a circular cross section with an outer diameter D and a length not less than 6D. The metal pipe includes a high-strength portion (A) and low-strength portions (B). The high-strength portion (A) is disposed along the entire circumference of the metal pipe to extend a dimension, as measured in the longitudinal direction of the metal pipe, that is not less than (⅔)D and not more than 3D of the metal pipe. The high-strength portion (A) has a yield strength not less than 500 MPa (or a tensile strength not less than 980 MPa). The low-strength portions (B) are disposed along the entire circumference of the metal pipe to be arranged in the longitudinal direction of the metal pipe to sandwich the high-strength portion (A). The low-strength portions (B) have a yield strength of 60 to 85% of that of the high-strength portion (A).