A flow rate control system includes a housing and a valve assembly slidingly disposed within a housing inner bore. The housing includes bypass openings. The valve assembly includes a valve and an orifice disposed in a valve inner bore. The valve includes a plurality of valve bypass bores extending axially through a valve collar. The valve assembly slides between closed and fully open positions. A spring biases the valve assembly toward the closed position in which the valve closes the housing bypass openings. In the open position, a bypass fluid path is formed including the valve bypass bores and the housing bypass openings. The valve assembly is flow rate controlled in the closed position and pressure controlled in the open position. The valve assembly may slide within a sleeve assembly including sleeve bypass openings, which connect the valve bypass bores and housing bypass openings in the bypass fluid path.

A tool for use in a wellbore includes a tubular body having a bore therethrough, an opening through a wall thereof, and a connector at each longitudinal end thereof; and an arm. The arm is pivotally connected to a first piston and rotationally coupled to the body, is disposed in the opening in a retracted position, and is movable to an extended position where an outer surface of the arm extends outward past an outer surface of the body. The first piston is disposed in the body bore, has a bore therethrough, and is operable to move the arm from the retracted position to the extended position in response to fluid pressure in the piston bore exceeding fluid pressure in the opening. The tool further includes a lock operable to retain the first piston in the retracted position; and a second piston operably coupled to the lock.

A flow rate control system includes a housing and a valve assembly slidingly disposed within a housing inner bore. The housing includes bypass openings. The valve assembly includes a valve and an orifice disposed in a valve inner bore. The valve includes a plurality of valve bypass bores extending axially through a valve collar. The valve assembly slides between closed and fully open positions. A spring biases the valve assembly toward the closed position in which the valve closes the housing bypass openings. In the open position, a bypass fluid path is formed including the valve bypass bores and the housing bypass openings. The valve assembly is flow rate controlled in the closed position and pressure controlled in the open position. The valve assembly may slide within a sleeve assembly including sleeve bypass openings, which connect the valve bypass bores and housing bypass openings in the bypass fluid path.

A downhole tool assembly coupled to a drill string includes a drill string motor that rotates the drill string, the downhole tool assembly including a tool body defining a perimeter, one or more cutting elements positioned on the perimeter of the tool body, where the one or more cutting elements are positionable between an extended position, in which the one or more cutting elements extend outwardly from the perimeter of the tool body, and a retracted position, where the one or more cutting elements are positioned further outward from the perimeter of the tool body in the extended position than the retracted position, and a tool motor coupled to the tool body, where the tool motor is structurally configured to rotate the tool body as fluid passes through the tool motor.

A packer apparatus usable in a well casing to provide an annular seal in the well casing. The packer apparatus includes an activation member mounted to the body wherein the activation member is moveable relative to the body to deform an elastomeric packer element outwardly relative to the body to form an annular seal in the well casing. A plurality of pistons is arranged to move the activation member relative to the body, each piston being disposed in a respective pressure chamber arranged to be filled with fluid in response to an increase in fluid pressure in the body.

A packer apparatus usable in a downhole well casing or an open borehole to provide an annular seal in the well casing or borehole. The packer apparatus includes an activation member disposed in body wherein the activation member is moveable relative to the body to deform an elastomeric packer element outwardly relative to the body to form an annular seal in a well casing in use. A plurality of pistons is arranged to move the activation member relative to the body, each piston being disposed in a respective pressure chamber arranged to be filled with fluid in response to an increase in fluid pressure in the body.

Apparatus (10) and method for removing a section of well tubing. A work string including a hydraulic tensioning device (14) and a section mill (12) a run in a rigless arrangement to provide continuous upward milling of the tubing (24) by raising the work string at a desired rate of progress. The hydraulic tensioning device (14) has a lower end (34) moveable longitudinally relative to the work string by application of fluid pressure in the work string to apply a weight on the section mill. The hydraulic tensioning device includes a self-correcting mechanism (30) to maintain the lower end at a position between a fully extended position and a fully retracted position to provide continuous milling of the tubing by the section mill at a milling rate matching the rate at which the work string is lifted. Embodiments are described for use in a rigless well abandonment procedure.

An apparatus is positioned within a wellbore in a subterranean formation. The apparatus includes a housing, a guide shaft, a follower, multiple underreamer blades, and a hydraulic chamber. The housing defines a track including multiple catch points. The guide shaft is disposed within the housing. The follower protrudes radially outward form the guide shaft and is received by the track. The follower and the track are cooperatively configured to restrict movement of the guide shaft relative to the housing. A rate of flow to the guide shaft is adjusted to adjust a relative position of the guide shaft with respect to the housing until the follower is located at one of the catch points. A pressure within the hydraulic chamber is adjusted to adjust a level of radially outward protrusion of the underreamer blades. The underreamer blades are rotated to cut into the subterranean formation.

To condition a wellbore with a reamer on a wireline, a portion of a wellbore is formed from a surface of the earth toward a subsurface hydrocarbon reservoir using a wellbore drilling assembly. After forming the portion of the wellbore, the wellbore drilling assembly is removed from the portion of the wellbore. Using a wireline, a wellbore sampling tool and a reamer are lowered into the portion of the wellbore. While maintaining the wellbore sampling tool and the wireline in a non-rotational state, the portion of the wellbore is cleaned using the reamer.

Method and apparatus for removing a section of well tubing. The well tubing (24) is milled in an upward direction on a hydraulic tensioning device (14) which maintains a constant load on the section mill so that long sections of tubing can be removed in a near continuous procedure on a single trip into the well. The hydraulic device includes an indicator (30) to provide a signal as the device nears each end of a stroke to inform a user that: the section mill is about to bottom out and the work string needs to be raised to extend the device; and the device is fully extended and can begin another stroke. Embodiments are described for use in a rigless well abandonment procedure.