Abstract: Various implementations described herein refer to a downhole device having a body with a cavity. The downhole device includes a mechanical element disposed within the cavity. The mechanical element has a base with a left-extending member and a right-extending member that holds the mechanical element in position within an interior space of the cavity. The downhole device includes an inflatable bladder disposed within the cavity between an interior sidewall of the cavity and the base of the mechanical element. The inflatable bladder has an opening on one end for receiving hydraulic fluid, and the inflatable bladder is activated and deactivated to selectively displace the mechanical element in and out of the cavity.

Abstract: A well tool apparatus comprises a control arrangement configured to control response of the downhole tool by varying a bore-annulus pressure difference. The control arrangement includes a valve piston longitudinally slidable in a generally tubular controller housing that is in operation substantially co-axial with the wellbore, to open or close a valve port to a fluid flow connection between the drill strings interior and the tool. A latch mechanism is configured to latch the valve piston against movement in one axial direction, keeping the valve piston in an open or a closed condition. Unlatching of the valve piston requires displacement thereof in the other axial direction to a mode change position. A stay member is automatically displaceable under hydraulic actuation responsive to bore-annulus pressure differences above a trigger threshold value, to obstruct movement of the latched valve piston under hydraulic actuation to the mode change position.

Abstract: Drilling dysfunction during simultaneous down-hole drilling and reaming is reduced by obtaining an indication of force on cutters of a reamer, determining whether or not the indication indicates an excessive force, and upon determining that the indication indicates an excessive force, extending drag elements from the bottom hole assembly to contact a wall of the well bore and reduce the force on the cutters of the reamer. The indication of force on the cutters can be obtained by sensing the weight on the drill bit, and the determination can be done by comparing the indicated weight on the drill bit to a first threshold and a second threshold.

Abstract: Drilling dysfunction during simultaneous down-hole drilling and reaming is reduced by obtaining an indication of force on cutters of a reamer, determining whether or not the indication indicates an excessive force, and upon determining that the indication indicates an excessive force, extending drag elements from the bottom hole assembly to contact a wall of the well bore and reduce the force on the cutters of the reamer. The indication of force on the cutters can be obtained by sensing the weight on the drill bit, and the determination can be done by comparing the indicated weight on the drill bit to a first threshold and a second threshold.

Abstract: A well tool apparatus comprises a control arrangement configured to control response of the downhole tool by varying a bore-annulus pressure difference. The control arrangement includes a valve piston longitudinally slidable in a generally tubular controller housing that is in operation substantially co-axial with the wellbore, to open or close a valve port to a fluid flow connection between the drill strings interior and the tool. A latch mechanism is configured to latch the valve piston against movement in one axial direction, keeping the valve piston in an open or a closed condition. Unlatching of the valve piston requires displacement thereof in the other axial direction to a mode change position. A stay member is automatically displaceable under hydraulic actuation responsive to bore-annulus pressure differences above a trigger threshold value, to obstruct movement of the latched valve piston under hydraulic actuation to the mode change position.

Abstract: A seal assembly for a reamer tool positionable in a wellbore includes an annular seal disposed in a longitudinal bore of a tool housing of the reamer tool; an annular wiper disposed upstream of the annular seal in the longitudinal bore; and a tubular sleeve coupled to and movable with a drive mechanism disposed in the longitudinal bore of the tool housing. The tubular sleeve is disposed in a radial gap between the drive mechanism and a surface of the longitudinal bore of the tool housing. The sleeve includes a radial opening through a sidewall of the sleeve, and the tubular sleeve is slidably engageable with the annular seal and with the annular wiper as the drive mechanism is moved through the longitudinal bore of the tool housing.