Abstract: Managing operation of a sealing element is described. In some aspects, failure of the sealing element of a pressure drilling system may be predicted. Deformation of the sealing element as a tool joint is pulled through the sealing element may be detected and tracked to determine if a deformation pattern of sealing element changes. Responses of sealing element due to one or more of stress, strain, temperature, mechanical load, and pressure using a network of sensors around sealing element can be detected. Responses may be tracked over time. Detected responses are compared to tracked responses to identify changes in the symmetry of responses over time or changes in magnitude of responses over time. Changes are associated with fractures occurring within sealing element. A remaining life of sealing element is predicted based on the changes and replacement may be scheduled based at least in part on the predicted remaining life.

Abstract: Wear sensors are provided on a drill bit or other rotary cutting tool which is for operation in a subterranean borehole and has a plurality of separate cutters protruding from a support structure towards the material to be cut by the tool. The electrically operated sensing means are located at or coupled to a sensing point within a protrusion from the support structure. This sensing point is located within a protrusion such that attrition of at least one cutter to a partially worn state brings the protrusion into abrasive contact with the material being cut and attrition of the protrusion then exposes the sensing point to the material which is being cut by the tool and thereby brings about a detectable change, which may include damage to the sensor at the sensing point, indicative of wear. The tool includes means to communicate data from the sensing means to the surface.

Abstract: A rotary cutting tool having a tool body insertable into a drill string with a plurality of projecting or extendable cutter assemblies at positions distributed azimuthally around the longitudinal axis of the tool body. Each cutter assembly includes a support structure bearing a plurality of cutters with exposed hard cutting surfaces facing in a direction of rotation of the tool. The support structure may have a surface positioned to contact a conduit wall and may be made as a body of particulate material infiltrated with a metal binder, where the particulate material may include material such as tungsten carbide having a Knoop hardness of at least 1000. The support structure may have a functionally graded composition with hard material to contact the wall and steel in a region which will be machined during manufacture.

Abstract: Systems and methods are provided for aligning pressure drilling system equipment. According to such methods, a longitudinal axis of a shaft of the pressure drilling system is determined. An offset between the axis of the shaft and a longitudinal axis of a blowout preventer is determined. A first adjustment component is coupled with the blowout preventer. A second adjustment component is aligned relative to the first adjustment component based on the measured offset. The second adjustment component is coupled with the first adjustment component. A rotating control device is coupled with the second adjustment component such that an axis of the rotating control device corresponds with the axis of the shaft to account for the measured offset.

Abstract: A method for detecting an influx and/or loss of circulation in a wellbore, comprising measuring a condition in the wellbore using a downhole sensor; determining that a positive displacement pump is shut off or turned on; predicting pit volume and/or gas concentration at a plurality of time points after the positive displacement pump is shut off or turned on using the measured condition in the wellbore prior to the positive displacement pump is shut off or turned on, wherein the measured condition correlates with the pit volume and/or gas concentration; measuring pit volume and/or gas concentration at the plurality of time points; comparing the predicted and the measured pit volumes and/or gas concentrations at the plurality of time points; and producing a warning signal if the difference between the predicted and the measured pit volumes and/or gas concentrations is greater than a pre determined value.

Abstract: A method for controlling a managed pressure drilling system including a drillstring located in a borehole, a pump that delivers drilling fluid, and a choke that controls the flow of the drilling fluid from an annulus formed between the drillstring and the wall of the borehole. During drilling, the drilling fluid flows downwardly through the drillstring from the pump and through a drill bit, and returns through the annulus to the choke. The method includes determining a correction ?Vcorr in the volume of the fluid in the annulus to achieve a target pressure in the fluid; calculating a choke flow rate correction term ?qcorr by dividing ?Vcorr by a factor related to the acoustic travel time ta of a pressure wave in the fluid travelling the length of the annulus; and determining a flow demand from the choke on the basis of the flow rate correction term ?qcorr.

Abstract: A rotary tool for milling tubing in a borehole comprises at least one cutter with a cutter body and a cutting surface on the body. Each cutter is shaped and positioned on the tool so as to reduce tensile stress in the cutter, thereby reducing risk of the cutter becoming chipped or broken in use and produces swarf of reduced rigidity, less likely to form a blockage in the borehole.

Abstract: A downhole cutting tool which may be a reamer or a mill has a rotary tool body with at least one block which carries hard-faced cutters and projects or is extensible from the tool body. A radially outward facing part of the cutter block defines a channel for fluid flow which extends generally axially along the cutter block. The channel is configured such that at least the rotationally trailing edge of the channel extends along the block in one or more directions which are inclined relative to the tool axis. This reduces or avoids the amount of channel edge parallel to the tool axis and thereby mitigates whirling and/or or vibration.

Abstract: A traction system for connecting and/or disconnecting pipe during well drilling is disclosed. The traction system of the present disclosure is installed above a rotating control device or blowout preventer and may be used with a continuous circulation device. The traction system uses a traction assembly that holds tension on a pipe to lift or hoist the pipe and that has two or more elements in contact with the pipe that spin around the pipe to rotate the pipe.

Abstract: Tubing in a borehole is removed using a rotary milling tool comprising a plurality of elements projecting from or extensible from the body of the tool. The elements are distributed azimuthally around the tool body. The elements comprise cutters to remove material from the tubing and outward facing guide surfaces for sliding contact with an inner surface of the tubing. As the tool is rotated and advanced, forward cutters contact the inner surface removing material from the tubing and exposing a renewed interior tubing surface with a diameter swept out by the cutter. The outward facing guide surfaces extend the same distance from the tool body as the forward cutters producing a sliding contact with the newly created inward facing surface. Further cutters, disposed behind the outward facing guide surfaces, with respect to motion of the tool through the tubing, remove the remaining portion of the tubing.

Abstract: A bell nipple for use in an offshore wellbore operation comprising an upper tubular member and a lower tubular member connected telescopically via a slip joint, one or more pistons at the level of the radial plane which is defined by the lowest point of the side outlet and each substantially not axially movable relative to the lower tubular member, wherein the total cross sectional area of the one or more pistons is substantially the same as the cross sectional area of the slip joint less the cross sectional area of the drillpipe. The one or more pistons in the bell nipple provides passive heave compensation in the system, so that the flow rate of drilling fluid measured along the flowline is free from perturbation due to heave during offshore operations.

Abstract: A reaming tool for enlarging an underground borehole comprises a plurality of cutter assemblies distributed azimuthally around a longitudinal axis of the tool, wherein each cutter assembly includes a supporting structure bearing a sequence of cutters which have hard surfaces exposed and facing in a direction of rotation of the tool. The outer surface of the support structure on each cutter assembly includes zones which each face towards an end of the assembly and is configured such that as it extends circumferentially relative to the tool axis in the direction opposite to rotation of the tool, it also extends away from an end of the assembly.

Abstract: A reamer for enlarging an underground borehole comprises a plurality of cutter assemblies distributed azimuthally around a longitudinal axis of the tool. Each cutter assembly comprises a supporting structure and a plurality of hard faced cutters secured therein with a hard surface of each cutter exposed and facing in a direction of rotation of the tool and extending radially outwards from the tool axis to a radially outward extremity. These cutters are arranged in a sequence extending axially along the tool. In contrast with convention a1 cutter assemblies, the supporting structure comprises at least one radially outward-facing surface which is positioned to follow behind the leading face of at least one cutter as the tool rotates and which is aligned with the radially outer extremity of the cutter at the same radial distance from the tool axis. Thus the surface area available to contact the borehole wall and stabilise the positioning and motion of the rotating reamer is enhanced.

Abstract: A reamer for enlarging an underground borehole comprises a plurality of cutter assemblies distributed azimuthally around a longitudinal axis of the tool, and each cutter assembly comprises a supporting structure and a plurality of hard faced cutters (211-216) embedded therein with a hard face of each cutter exposed and facing in a direction of rotation of the tool. Each cutter assembly includes at least one outward-facing gauge surface (220), at a radial distance from the tool axis which aligns the gauge surface with the radially outer extremity (218) of at least one cutter. This gauge surface (220) extends (221) in the direction of rotation circumferentially ahead of the extremity of the exposed face of the aligned at least one cutter. It may meet the side of the assembly at a curved (222) or bevelled (342) edge and may also extend back from the exposed face of the cutter.

Abstract: A reaming tool for enlarging an underground borehole has a plurality of cutter assemblies distributed azimuthally around a longitudinal axis of the tool. First, second and possibly more cutter assemblies each have an axially extending length comprising supporting structure bearing a sequence of cutters which have hard surfaces facing in a direction of rotation of the tool and are distributed axially along the length. A plurality of the cutters on the second cutter assembly are at axial positions relative to the tool which are intermediate between axial positions of the cutters on the first cutter assembly. Cutters on further assemblies may also be at intermediate axial positions. Cutters in the overall plurality of sequences are positioned at radial distances from the tool axis which increase as axial distance from an end of the tool increases.

Abstract: A rotary cutting tool, which may be a reamer for enlarging an underground borehole or a mill to remove tubing by cutting into the inside wall of the tubing, has a plurality of cutter assemblies distributed azimuthally around a longitudinal axis of the tool, wherein each cutter assembly includes a supporting structure bearing a sequence of cutters which extends axially along the tool with leading surfaces facing in a direction of rotation of the tool. The cutters of each sequence are positioned at a plurality of circumferential positions such that no more than three cutters of the sequence are aligned on any line parallel to the longitudinal axis of the tool. In an overlapping arrangement, a plurality of cutters in the sequence may have a leading face circumferentially behind the leading face but ahead of the trailing end of at least one other cutter.

Abstract: A reaming tool for enlarging an underground borehole comprises a plurality of cutter assemblies (251, 252, 253) distributed azimuthally around a longitudinal axis of the tool, wherein each cutter assembly comprises support structure bearing a sequence of cutters (211-214) with leading surfaces facing in a direction of rotation of the tool and the sequence of cutters extends axially along the tool from an axial end (202) of the tool with the cutters positioned at radial distances from the tool axis which progressively increase as the sequence extends away from the axial end of the tool. The cutter assemblies include guiding structure (261-264) which is positioned circumferentially ahead of the leading faces of cutters of the sequence on the assembly.

Abstract: Monitoring one or more items of equipment associated with a borehole or other conduit. A sensor system includes a vibration sensor for sensing vibrations at one or more sensor locations associated with one or more items of the equipment and/or the borehole or other conduit. A processing system processes the sensor information to determine a characteristic of the operation of the one or more items of equipment and/or the borehole or other conduit.

Abstract: A drilling procedure is operated such that a formation around the wellbore being drilled is fractured and then reservoir fluids from a hydrocarbon reservoir contained in the formation are flowed into the wellbore where the flow of the reservoir fluids is tested. Production predictions for the wellbore are processed from the measurements made on the flow of reservoir fluids and decisions regarding further drilling operations are made based upon the reservoir fluid measurements. By testing reservoir fluids prior to completing the wellbore, drilling operations such as, for example, continuing to drill the wellbore may be made without tripping the drillstring from the wellbore.

Abstract: A downhole rotary tool for comminuting tubing in a borehole comprises a tool body and a plurality of cutting assemblies projecting from or extensible from the tool body and distributed azimuthally around a longitudinal axis of the tool body. Each cutting assembly comprises a supporting structure and a plurality of cutters with cutting surfaces of hard material. The rotating tool is advanced into initial contact with the tubing to commence milling axially along the tubing and then advanced further to continue milling the tubing, At least one cutting assembly has material which is softer than the hard faces of the cutters and is positioned to contact the tubing at the initial contact and delay contact between at least one hard surfaced cutter and the tubing.