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:
Nov. 20, 2018
Filed:
Dec. 25, 2014
Mitsubishi Hitachi Power Systems, Ltd., Kanagawa, JP;
Hiroyuki Nakaharai, Tokyo, JP;
Yuichi Kanemaki, Tokyo, JP;
Kazuhiro Domoto, Kanagawa, JP;
Yoshinori Yamasaki, Kanagawa, JP;
MITSUBISHI HITACHI POWER SYSTEMS, LTD., Kanagawa, JP;
Abstract
A heat transfer tube for a boiler, an interior of the heat transfer tube having a supercritical pressure and being configured to have a heating medium flow therethrough, includes: a groove portion defined on an inner circumferential surface and having a spiral shape extending continuously toward a tube axis direction; and a rib portion extending continuously and protruding inward in a radial direction by the groove portion of the spiral shape. In a cross section taken along the tube axis direction, a width of the groove portion in the tube axis direction is defined as Wg, a height of the rib portion in the radial direction is defined as Hr and a tube outer diameter is defined as D, and the width Wg of the groove portion, the height Hr of the rib portion, and the tube outer diameter D satisfy Wg/(Hr·D)>0.40.