A drill string apparatus includes an upper casing section having a port collar. The port collar provides a controllable opening from an interior of the upper casing section to an annulus around the upper casing section. A lower casing section is coupled to the upper casing section through a swivel. The lower casing section includes an external casing packer and a casing pad coupled to an external portion of the lower casing section. The external casing packer is expandable to an annulus around the lower casing section before a cement operation to avoid cement loss circulation to weak formation below the packer. Methods and systems are also disclosed.

A belling auger includes a rotatable shaft, a main shaft extending through the rotatable shaft, a sliding sleeve mounted on the main shaft a bottom panel and a shovel rotatably attached to the rotatable shaft. Pressing the rotatable shaft down towards the sliding sleeve causes the shovel to hinge outward at the bottom of a piling hole. As the device rotates the shovel scoops dirt onto the pan, thus widening the bottom of the hole to a bell or cone shape.

The invention discloses an anchor rod multi-section reaming machine tool and an application thereof. The machine tool is used cooperatively with an anchor rod drill rig (M), wherein a hydraulic cylinder (41) is connected with a hydraulic station (1) through a pipe, and the hydraulic cylinder (41) is fixed at a lower end of a drill rod (M1) of the anchor rod drill rig (M) and connected with the hydraulic station (1). A piston (412) is arranged inside a cylinder body (411) of the hydraulic cylinder (41) and axially moves relative to the cylinder body (411) such that the cylinder body (411) is divided into a hydraulic cylinder upper chamber (4111) and a hydraulic cylinder lower chamber (4112) which have variable volume. An upper end of a piston rod (413) is fixed at a lower portion of the piston (412) and a lower end of the piston rod (413) is fixed at an upper portion of an arch pressing device fixing disc (42); and an arch pressing device (43) comprises a pair of upper arch arms (431) and a pair of lower arch arms (432), upper ends of the upper arch arms (431) are rotatably connected with a central position of a lower portion of the arch pressing device fixing disc (42), lower ends of the upper arch arms (431) are rotatably connected with upper ends of the lower arch arms (432), and lower ends of the lower arch arms (432) are rotatably connected with a central position of an upper portion of a base plate (44). The machine tool can perform multi-site variable-section reaming at different positions and improve the anti-pull-out property of an anchor rod.

The invention discloses an anchor rod multi-section reaming machine tool and an application thereof. The machine tool is used cooperatively with an anchor rod drill rig (M), wherein a hydraulic cylinder (41) is connected with a hydraulic station (1) through a pipe, and the hydraulic cylinder (41) is fixed at a lower end of a drill rod (M1) of the anchor rod drill rig (M) and connected with the hydraulic station (1). A piston (412) is arranged inside a cylinder body (411) of the hydraulic cylinder (41) and axially moves relative to the cylinder body (411) such that the cylinder body (411) is divided into a hydraulic cylinder upper chamber (4111) and a hydraulic cylinder lower chamber (4112) which have variable volume. An upper end of a piston rod (413) is fixed at a lower portion of the piston (412) and a lower end of the piston rod (413) is fixed at an upper portion of an arch pressing device fixing disc (42); and an arch pressing device (43) comprises a pair of upper arch arms (431) and a pair of lower arch arms (432), upper ends of the upper arch arms (431) are rotatably connected with a central position of a lower portion of the arch pressing device fixing disc (42), lower ends of the upper arch arms (431) are rotatably connected with upper ends of the lower arch arms (432), and lower ends of the lower arch arms (432) are rotatably connected with a central position of an upper portion of a base plate (44). The machine tool can perform multi-site variable-section reaming at different positions and improve the anti-pull-out property of an anchor rod.

Latchable casing while drilling systems and methods are disclosed. Some system embodiments include a casing string including an upper latch apparatus and a lower latch apparatus. The system also includes a bottom hole assembly (BHA) latched into the lower latch apparatus for steerable drilling, the BHA configured to latch into the upper latch apparatus for enlarging a rat hole.

Latchable casing while drilling systems and methods are disclosed. Some system embodiments include a casing string including an upper latch apparatus and a lower latch apparatus. The system also includes a bottom hole assembly (BHA) latched into the lower latch apparatus for steerable drilling, the BHA configured to latch into the upper latch apparatus for enlarging a rat hole.

Expandable reamers for enlarging a borehole in a subterranean formation include a tubular body, at least one curved blade track carried by the tubular body, and at least one blade engaged with the at least one blade track and configured to slide along the curved blade track along a curved path between a first retracted blade position and a second expanded blade position. To form such an expandable reamer, a tubular body having at least one curved blade track carried by the tubular body may be formed, and at least one blade may be engaged with the blade track. The blade and blade track may be configured such that the blade slides along the blade track along a curved path between a retracted position and an expanded position. Such expandable reamers may be used to enlarge boreholes in subterranean formations.

Expandable reamers for enlarging a borehole in a subterranean formation include a tubular body, at least one curved blade track carried by the tubular body, and at least one blade engaged with the at least one blade track and configured to slide along the curved blade track along a curved path between a first retracted blade position and a second expanded blade position. To form such an expandable reamer, a tubular body having at least one curved blade track carried by the tubular body may be formed, and at least one blade may be engaged with the blade track. The blade and blade track may be configured such that the blade slides along the blade track along a curved path between a retracted position and an expanded position. Such expandable reamers may be used to enlarge boreholes in subterranean formations.

A steerable well bore drilling device and method are disclosed. The steerable well bore drilling device comprises a drill string, a bit coupled to the drill string, a drilling motor within the drill string and driving the bit, and a pair of eccentric reamers coupled to the drill string and positioned between the bit and the motor.

A steerable well bore drilling device and method are disclosed. The steerable well bore drilling device comprises a drill string, a bit coupled to the drill string, a drilling motor within the drill string and driving the bit, and a pair of eccentric reamers coupled to the drill string and positioned between the bit and the motor.