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. 13, 1981
Filed:
Oct. 19, 1979
Robert Desbrandes, Sevres, FR;
Pierre Grolet, Orgerus, FR;
Institut Francais du Petrole, Rueil-Malmaison, FR;
Abstract
This device comprises a resilient stress-responsive member interconnecting two conduits which can be respectively coupled to upper and lower portions of the downhole assembly, and are surrounded by a protecting sleeve making up with one of said conduits, the lateral walls of an annular space. Annular elements secured to a first of said lateral walls, and slidable on the second of said lateral walls, form the end walls of said space and an intermediate annular piston integral with the second lateral wall, and slidable on the first lateral wall, divides the annular space into two annular chambers communicating respectively with the inner and outer spaces of the downhole assembly of the drill string, and having operative cross sections selected so as to compensate for the axial loads due to the hydrostatic pressure and bottom effect applied to the stress-responsive member.