Underreamer with adjustable cutter block expansion
AssigneeSmith International, Inc.
InventorJianbing Hu
Life of this patent
Estimating the term…
Abstract
An underreamer for increasing a diameter of a wellbore. The underreamer includes a body having an axial bore extending at least partially therethrough. A sleeve is arranged and designed to move a first axial distance within the body. A cutter block is movably coupled to the body. The cutter block is arranged and designed to move at least the first axial distance with respect to the body to contact the sleeve in response to hydraulic pressure in the bore. The cutter block moves from a first outer diameter to a second outer diameter as the cutter block moves the first axial distance.
Claims20
An underreamer for increasing a diameter of a wellbore, comprising:
- a body;
- a sleeve within the body;
- an actuator arranged and designed to control axial movement of the sleeve within the body between one or more axial positions;
- a cutter block coupled to the body and arranged and designed to move between a radially retracted position and one or more radially expanded positions in response to hydraulic pressure in the body;
- and
- a stopper within the body and arranged and designed to move within the body to one or more axial positions, the one or more axial positions of the stopper corresponding to the one or more radially expanded positions of the cutter block and to the one or more axial positions of the sleeve as controlled by the actuator.
A method for increasing a diameter of a wellbore, comprising:
- inserting an underreamer in a wellbore while a cutter block of the underreamer is in a radially retracted position relative to a body of the underreamer;
- applying hydraulic force to move a cutter block of the underreamer from the radially retracted position to a first radially expanded position, wherein moving the cutter block includes engaging the cutter block against a stopper within the body;
- operating an actuator of the underreamer to move a sleeve of the underreamer a first axial distance within the body;
- moving the stopper the first axial distance within the body;
- and
- applying hydraulic force to move the cutter block at least the first axial distance to a second radially expanded position, wherein moving the cutter block includes engaging the cutter block against the stopper within the body.
Dependencies are inferred from the claim text.