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:
Sep. 26, 2023
Filed:
Jul. 09, 2021
Applicant:
Kureha Corporation, Tokyo, JP;
Inventor:
Shinya Takahashi, Tokyo, JP;
Assignee:
KUREHA CORPORATION, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B 34/14 (2006.01); E21B 29/00 (2006.01); E21B 43/14 (2006.01); E21B 43/26 (2006.01);
U.S. Cl.
CPC ...
E21B 34/142 (2020.05); E21B 43/14 (2013.01); E21B 43/26 (2013.01);
Abstract
In a dart for a downhole device according to the present invention, a ball is formed of a first degradable material having a first degradation rate, a mandrel is formed of a second degradable material having a second degradation rate lower than the first degradation rate, and a sleeve is formed of the second degradable material or a third degradable material having a third degradation rate lower than the second degradation rate.