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:
Mar. 06, 1979
Filed:
Mar. 30, 1977
Yuji Yoshitomi, Kudamatsu, JP;
Zensuke Tamura, Kudamatsu, JP;
Hideaki Kamohara, Kudamatsu, JP;
Keiji Omura, Kudamatsu, JP;
Yoshimasa Murakami, Kudamatsu, JP;
Tadasi Takata, Kudamatsu, JP;
Teruo Nuwa, Kudamatsu, JP;
Hitachi, Ltd., , JP;
Abstract
A tube-hole structure for an expanded tube-to-tube-sheet joint which is formed by axially moving a rod within each tube member in each tube hole of the tube sheet by external drive means, thereby imparting an elastic mass placed inside the tube with a sufficient compressive load to expand the tube uniformly in the radial direction to provide a rigid joint between the tube and tube hole, characterized in that each tube hole has at least one circumferential groove with an axial dimension or length of 1.5/.beta. to 3.0/.beta. (.beta. being ##EQU1## WHERE R is the mean radius of the tube member to be expanded, t is the wall thickness of the tube, and .nu. is the Poisson's ratio).