Abstract: A well tool apparatus comprises a control arrangement configured to control response of the downhole tool by varying downhole drilling fluid conditions. 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 in an activated mode and/or a deactivated mode. Unlatching of the valve piston can be effected by displacement thereof in a particular axial direction to a mode change position. A stay member is automatically displaceable in the particular actual direction under hydraulic actuation responsive to above-threshold drilling fluid conditions, to obstruct movement of the valve piston under hydraulic actuation to the mode change position.

Abstract: A flexible reamer housing includes a tubular central portion including a tool bay with an aperture to allow a reamer cutter arm within the tool bay to move radially outward through the aperture, and tubular first and second auxiliary portions arranged toward opposite ends of the central portion. The first and second auxiliary portions each include a first stiffness that is less than a second stiffness of the central portion.

Abstract: A flow-diverter assembly includes a housing having a discharge port, a valve piston located in the housing, and a barrel cam coupled to the valve piston. The valve piston includes a valve body in fluid communication with an internal flow passage of the housing, and is movable axially along a longitudinal axis of the housing between an open position, where a vent of the valve body is fluidly coupled to the discharge port, and a closed position, where the vent of the valve body is substantially sealed from the discharge port.

Abstract: A well tool apparatus comprises a control arrangement configured to control response of the downhole tool by varying downhole drilling fluid conditions. 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 in an activated mode and/or a deactivated mode. Unlatching of the valve piston can be effected by displacement thereof in a particular axial direction to a mode change position. A stay member is automatically displaceable in the particular actual direction under hydraulic actuation responsive to above-threshold drilling fluid conditions, to obstruct movement of the valve piston under hydraulic actuation to the mode change position.

Abstract: A flow-diverter assembly includes a housing having a discharge port, a valve piston located in the housing, and a barrel cam coupled to the valve piston. The valve piston includes a valve body in fluid communication with an internal flow passage of the housing, and is movable axially along a longitudinal axis of the housing between an open position, where a vent of the valve body is fluidly coupled to the discharge port, and a closed position, where the vent of the valve body is substantially sealed from the discharge port.

Abstract: A flexible reamer housing includes a tubular central portion including a tool bay with an aperture to allow a reamer cutter arm within the tool bay to move radially outward through the aperture, and tubular first and second auxiliary portions arranged toward opposite ends of the central portion. The first and second auxiliary portions each include a first stiffness that is less than a second stiffness of the central portion.