A conductor assembly comprising a conductor of an offshore platform and a guide surrounding the conductor. The guide extending from an upper end to a lower end and having a main portion therebetween, a stabilising body defining a bore extending therethrough, the conductor extending through the bore of the stabilising body, the stabilising body provided between the conductor and the guide optionally the stabilising body comprising an inner body and an outer body. In this way, the conductor is allowed to move vertically within the guide with the only moving surfaces in contact being an outer surface of the inner body and the inner surface of the outer body, thus mitigating or eliminating abrasion of the conductor and/or guide.

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 shank adapter, rock drilling machine and method of mounting a shank adapter of a rock drilling machine inside a slide bearing element. The shank adapter includes a coupling head and a rotation portion at its opposite ends, and a flushing portion located therebetween. Outer diameters of the coupling head and the rotation portion are both greater than outer diameters of portions of the shank adaptor located therebetween.

Adjustment of the angle of a bent sub or other steering feature in a drill string relative to a reference angle of a downhole sensor is facilitated by a rotatable coupling between the bend sub and the sensor. The rotatable coupling may be rotated to align the high side with a reference indicia and locked at the set angle. Calibration of the sensor is facilitated and opportunities for certain measurement errors are eliminated. An embodiment provides a locking mechanism comprising tapered locking fingers which are clamped against a surface by a tapered collar. Rows of ceramic balls retained in circumferential channels may be provided to permit rotation while carrying tensile and compressional forces.

An apparatus and method for reducing torque in a drill string, in which the apparatus includes a first clamp assembly including a plurality of arcuate clamp segments that are pivotally connected together, the plurality of arcuate clamp segments being configured to be positioned around and secured to an oilfield tubular so as to be rotationally fixed to the oilfield tubular, and an outer sleeve positioned around the first clamp assembly. The outer sleeve includes at least two sleeve segments assembled together to form a generally cylindrical sleeve around the first clamp assembly, and the first clamp assembly is configured to rotate with the oilfield tubular and with respect to the outer sleeve.

The invention belongs to the technical field of drills for petroleum, coal mines and exploration, and provides a whipstocking drill for an ultra-short-radius well. The whipstocking drill comprises several flexible drill rods which are sequentially connected end to end, wherein the flexible drill rod at an end portion is connected with a length compensation device, and the flexible drill rods are externally sleeved with several guide sleeves which are movably connected. The invention solves the technical problems of a long whipstocking length and an excessively large turning radius of curvature during whipstocking.

A system for centering a reinforcing member within a drilled shaft/bore hole includes a first cage member and a second cage member. The first cage member is operable to surround a first half of the reinforcing member. The second cage member is operable to surround a second half of the reinforcing member. The second cage member is operably connected to the first cage member, and the first and second cage members have identical shapes.

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.

An apparatus including an external surface portion shaped so as to mate with a docking device, and two half-shells having internal surfaces of semi-circular cross section. The apparatus further includes a plurality of segments arranged inside the two half-shells and including teeth for gripping onto a shaft, and an installation tool operable to cause the two half-shells to close around the shaft, thereby securing the apparatus to the shaft.

A system and a method for providing an external thread on a cylinder. The system includes a circumferential groove in an exterior surface of the cylinder and a split ring. The split ring has a lug on an interior side for inserting within the groove and has the external thread on an exterior side. The split ring may include a shoulder on the exterior side of the split ring for providing a torquing surface. The system may include a retaining mechanism for inhibiting rotation of the split ring within the groove. The retaining mechanism may include a slot in the groove and a key for inserting within the slot and within a gap in the split ring. Systems and methods for threadably connecting a tool, component or object having an internal thread with a cylinder having an external thread. The external thread on the cylinder may be provided using the system for providing an external thread on a cylinder, may be integral with the cylinder, or may be provided in some other manner. The cylinder may be a housing and the tool, component or object may be a stabilizer.