Abstract:
A drill bit includes a bit body; a pad associated with the bit body; and a rate control device coupled to the pad that extends from a bit surface at a first rate and retracts from an extended position to a retracted position at a second rate in response to external force applied onto the pad. The rate control device includes a piston for applying a force on the pad; a biasing member that applies a force on the piston to extend the pad at the first rate; a fluid chamber associated with the piston; and a pressure management device for controlling a fluid pressure within the fluid chamber.
Abstract:
A backup ring for a face seal in a roller cone bit is configured to resist wear from drilling fluids present adjacent exposed faces of the backup ring. Portions are removed from an exposed end face in a variety of shapes while the hardness of the material is increased. The removal of material offsets an increase in force that would be transmitted through the backup ring on face seal assembly due to flexing. A spring can optionally be included in the removed material location. Another way is to increase the edge density of all or part of the exposed edges while leaving the interior portions unaffected by using electron beam radiation to increase the crosslink density or by other techniques that allow a unitary structure with a more durable edge region.
Abstract:
A backup ring for a face seal in a roller cone bit is configured to resist wear from drilling fluids present adjacent exposed faces of the backup ring. Portions are removed from an exposed end face in a variety of shapes while the hardness of the material is increased. The removal of material offsets an increase in force that would be transmitted through the backup ring on face seal assembly due to flexing. A spring can optionally be included in the removed material location. Another way is to increase the edge density of all or part of the exposed edges while leaving the interior portions unaffected by using electron beam radiation to increase the crosslink density or by other techniques that allow a unitary structure with a more durable edge region.
Abstract:
Earth-boring tools may include a body and a passively adjustable, aggressiveness-modifying member secured to the body. The passively adjustable, aggressiveness-modifying member may be movable between a first position in which the earth-boring tool exhibits a first aggressiveness and a second position in which the earth-boring tool exhibits a second, different aggressiveness responsive to forces acting on the passively adjustable, aggressiveness-modifying member.
Abstract:
Earth-boring tools may include a body and a passively adjustable, aggressiveness-modifying member secured to the body. The passively adjustable, aggressiveness-modifying member may be movable between a first position in which the earth-boring tool exhibits a first aggressiveness and a second position in which the earth-boring tool exhibits a second, different aggressiveness responsive to forces acting on the passively adjustable, aggressiveness-modifying member.
Abstract:
Earth-boring tools may include a body and a passively adjustable, aggressiveness-modifying member secured to the body. The passively adjustable, aggressiveness-modifying member may be movable between a first position in which the earth-boring tool exhibits a first aggressiveness and a second position in which the earth-boring tool exhibits a second, different aggressiveness responsive to forces acting on the passively adjustable, aggressiveness-modifying member.
Abstract:
A self-adjusting earth-boring tool includes a body carrying cutting elements and an actuation device disposed at least partially within the body. The actuation device may include a first fluid chamber, a second fluid chamber, a first reciprocating member, and a second reciprocating member. The first and second reciprocating members may divide portions of the first fluid chamber from portions of the second fluid chamber. A connection member may be attached to both of the first and second reciprocating members and may have a drilling element removably coupled thereto. A first fluid flow path may extend from the second fluid chamber to the first fluid chamber. A second fluid flow path may extend from the first fluid chamber to the second fluid chamber.
Abstract:
In one aspect, a drill bit is disclosed, including: a bit body; a pad associated with the bit body; a rate control device coupled to the pad that extends from a bit surface at a first rate and retracts from an extended position to a retracted position at a second rate in response to external force applied onto the pad, the rate control device including: a piston for applying a force on the pad; a biasing member that applies a force on the piston to extend the pad at the first rate; a fluid chamber associated with the piston; and a pressure management device for controlling a fluid pressure within the fluid chamber.
Abstract:
A backup ring for a face seal in a roller cone bit is configured to resist wear from drilling fluids present adjacent exposed faces of the backup ring. Portions are removed from an exposed end face in a variety of shapes while the hardness of the material is increased. The removal of material offsets an increase in force that would be transmitted through the backup ring on face seal assembly due to flexing. A spring can optionally be included in the removed material location. Another way is to increase the edge density of all or part of the exposed edges while leaving the interior portions unaffected by using electron beam radiation to increase the crosslink density or by other techniques that allow a unitary structure with a more durable edge region.
Abstract:
A method of improving the service life of a drill bit comprises creating a weldment between load bearing portions of the drill bit where the weldment has a preselected root gap greater than about 25 mils and a preselected root face greater than about 25 mils, and where the weldment has a material property greater than the materials being joined.