A modified tubular, particularly a drill pipe (12) has a composite non-rotating drill pipe protector assembly (1) including first and second composite collars (2, 3) provided as cooperating parts positionable around the drill pipe (12) and bondable thereto using bonding agent, a non-rotating composite protector shell (4), provided as cooperating shell parts and an internal polymeric radial bearing (7) which fits within a recess (41) within the non-rotating composite protector shell (4) and has an internal surface (10) configured to provide a plurality of internal fluid flow channels (11). An external surface of the non-rotating composite protector shell (4) has blades (14), spaced apart by fluid flow by-pass channels (24). In use the rotation of the drill pipe facilitates fluid movement within the non-rotating composite protector shell by creating a pumping effect inducing ingress of fluid and through-flow within the internal polymeric radial bearing (7).

An apparatus for mounting on a tubular structure, such as a casing or drill string having a longitudinal axis, that may reduce friction of the tubular structure in a horizontal or deviated well comprises a tubular segment for mounting over the casing or drill string such that the apparatus is freely rotatable about the longitudinal axis. The apparatus also includes a plurality of ridges on an outer face of the tubular segment, the ridges being at an angle to an axial direction of the tubular segment to cause the apparatus to rotate responsive to movement of the apparatus against a wall of a wellbore as the apparatus traverses the wellbore. The raised ridges have a non-uniform height from the outer face of the tubular segment.

Downhole plug assemblies comprising plug, release sleeve and collet adapter and methods thereof are disclosed. The plug comprises of a mandrel with a bore and an outer subassembly comprising a top element, anchoring system, sealing system and a nose element. The release sleeve is engaged and secured within the bore at a proximal portion by a plurality of shearable fastening members. The collet adapter comprises of a plurality of fingers with each finger ending in a head at the tip. The collet head is engaged with a slanting face of the release sleeve at a lower end and is configured to be engaged with a setting tool at an upper end. During the release process, the fingers expand to prevent disengaging from the face thus transferring the load to the release sleeve and causing the fastening members to shear off and the release sleeve to release from the mandrel.

An antirotation stabilizer may include one or more antirotation pads extending from a stabilizer body. Each antirotation pad may be positioned at least partially within a recess formed in the stabilizer body. Each antirotation pad may be coupled to a torsion bar. The torsion bar may couple between the antirotation pad and the stabilizer body and may be under torsional loading such that the antirotation pad is extended from the stabilizer body. The antirotation stabilizer may include one or more rollers.

The disclosure of this application is directed to a downhole tool comprising a central element/member and a sleeve that is rotatably and orbitally disposed around the central element/member. The sleeve rotates and orbits around the central element/member responsive to fluid flowing through the downhole too. The disclosure is also related to a method of advancing the downhole tool in a well by flowing fluid through the tool.

A connection mechanism (4) comprises first and second components (6, 8) which can be selectively coupled together, one of the first or second components comprises a locking member (25) which is moveable between a first state and a second state, the other of the first or second component comprises means (16) for initially moving the locking member from the first to the second state as the first and second components are initially drawn together and means (19) for returning the locking member to the first state once the first and second components are fully engaged together to prevent disengagement of the first and second components.

A rotating control device (RCD) for use in pressurized drilling operations. The RCD having a non-rotating RCD housing enclosing an elongate passage, a tubular RCD mandrel extending along the elongate passage of the RCD housing, wherein the RCD mandrel has a longitudinal axis and is configured in use to rotate relative to the RCD housing about the longitudinal axis, and a stripper element which is mounted on an end of the RCD mandrel and which is configured to seal against and rotate with a tubular drill pipe extending along the elongate passage of the RCD housing, wherein the stripper element is secured to the end of the RCD mandrel by a flexible sleeve which is more flexible than the stripper element.

Some embodiments of the disclosure relate to an apparatus that may reduce friction of a tubular structure in horizontal or deviated well. An apparatus is provided for mounting on a tubular structure, such as a casing or drill string having a longitudinal axis. The apparatus comprises a tubular segment for mounting over the casing or drill string such that the apparatus is freely rotatable about the longitudinal axis. The apparatus also includes a plurality of ridges on the outer face of the tubular segment, the ridges being at an angle to an axial direction of the tubular segment to cause the apparatus to rotate responsive to movement of the apparatus against a wall of the wellbore as the apparatus traverses the wellbore. The raised ridges have a non-uniform height from the outer face of the tubular segment.

An apparatus for reducing torque in a drill string includes a clamp assembly having a first clamp segment and a second clamp segment, the first and second clamp segments each including two circumferential ends, the two circumferential ends of the first clamp segment being configured to be connected to the two circumferential ends of the second clamp segment so as to secure the clamp assembly around an oilfield tubular and prevent the clamp assembly from rotating relative to the oilfield tubular. An outer diameter surface of each of the first and second clamp segments is generally continuous in an axial direction. The apparatus also includes an outer sleeve positioned around the clamp assembly, wherein the clamp assembly is configured to rotate with the oilfield tubular and with respect to the outer sleeve.

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.