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:
Feb. 21, 1995
Filed:
May. 11, 1993
Roger Tailby, .ANG.lg.ang.rd, NO;
Den Norske Stats Oljeselskap A.S, Stavanger, NO;
Abstract
Hydraulic tool for carrying out relative axial movements in an oil or gas well by means of hydraulic pressure through a hollow tubing string, comprising a cylindrical tool housing and axially movable cylinder-piston members in the housing. There are provided concentric, hollow cylinders (20,30) each being separately movable axially in said housing (10), and an inner piston (40) being axially movable within an adjacent cylinder (30). Breakable retaining elements (31,32) keep said inner piston (40) and said adjacent cylinder (30) in an initial position until said retaining elements are overcome by the hydraulic pressure. Thrust dogs (21,22) cooperate with recesses (88) in a surrounding tubing component (80) where axial movement of said outer cylinder (20) causes radial expansion of said thrust dogs (21,22), by means of conical surfaces (23) on said outer cylinder (20). A spring (27) acts against said axial movement of the outer cylinder (20) to return the cylinder to its initial position upon termination of the hydraulic pressure. Projecting members (29,18 and 62,66) of at least one cylinder (30) and said inner piston (40) are pushed out of said housing (10) by sequential exposure to said hydraulic pressure, for carrying out a sequence of relative axial movements.