Casing cutter
AssigneeDeltide Fishing & Rental Tools, Inc.
InventorDavid J. Ruttley
Life of this patent
Estimating the term…
Abstract
Casing cutter for severing multiple tubulars in a well bore has a pair of cutter blades pivotally mounted on a support body. The blades are pivotally mounted for gradual movement outside of the support body when downward force is applied to proximate ends of the cutter blades. The support body is rotated inside the innermost of the multiple tubulars, while the cutter blades sever the tubulars of progressively increasing diameter.
Claims24
An apparatus for severing multiple tubulars in a well bore, comprising:
- an elongated hollow body adapted for receiving torque from an external rotational source;
- a pair of cutter blades pivotally mounted in said body for cutting through walls of the tubulars, said cutter blades comprising a main top surface and a distal end wall, and
- wherein cutting elements are located on said main top surface and said distal end wall;
- and
- a means for gradually pivotally moving the cutter blades from an idle position recessed in the hollow body to a position substantially perpendicular to the vertical axis of the body;
- and a means for lowering said body into a well bore.
An apparatus for severing multiple tubulars in a well bore, comprising:
- a hollow support body adapted for lowering into a well bore;
- at least one longitudinal blade slot through said support body, to allow passage of a pair of cutter blades in opposite directions therethrough;
- and a vertical force transfer element mounted in said support body, for transferring downward vertical force from an external power source to the cutter blades and causing the cutter blades to extend outwardly from said support body, said vertical force transfer element comprising a piston and wherein a pair of alignment members are positioned adjacent a lower portion of the piston to ensure alignment of the piston when the vertical force is applied to the piston.
A method of severing multiple tubulars in a well bore, comprising the steps of:
- providing a hollow support body carrying a pair of pivotally moveable first set of a pair of cutter blades;
- providing a means for applying pivotal force on the cutter blades and for moving the cutter blades outwardly from the support body;
- lowering the support body into the innermost of said multiple tubulars;
- applying rotational force to said support body, while applying a downward force on the cutter blades, thereby causing the cutter blades to cut through a wall of the innermost of the multiple tubulars, each of said cutter blades having an end and an upper surface, and wherein cutting elements are positioned on said end and said upper surface.
Dependencies are inferred from the claim text.