There are described devices and methods for use, for example, with signaling in a well, e.g. using a well structure of the well. Such signaling may include the communication of power and/or data signals. The devices and methods used may assist with efficient and/or effective communication of such signals. In some examples, there is described deployable devices and methods, e.g. a deployable device for signaling contact in a well, and methods associated therewith.

A drilling system includes a drill string for connecting with a drill bit for drilling a borehole, a fixed stabilizer fixed on the drill string, and an active stabilizer including a body and actuators connecting the body and the drill string. The actuators are capable of driving the drill string away from a center of the borehole with a displacement. The body has an outer surface for contacting a wall of the borehole, an inner surface facing the drill string, and at least one guiding portion projecting from the inner surface and each defining at least one groove. The drill string includes at least one sliding portion slidable within the at least one groove respectively to constrain movement between the drill string and the active stabilizer along an axial direction of the drill string and guide movement between the drill string and the active stabilizer perpendicular to the axial direction.

The present invention relates to a stabilizing system (100) adapted to be used in a deep drilling system. The stabilizing system (100) comprises a longitudinal housing (110) and a spring (140) preferably a helical spring, arranged inside the housing (110). Thereby, the stabilizing system (100) is contracted and the spring (140) is compressed along the longitudinal axis of the stabilizing system (100) when an external load is applied in longitudinal direction onto the stabilizing system (100). The transversal diameter of the stabilizing system (100) increases when the stabilizing system (100) is contracted. Further, the transversal diameter of the stabilizing system (100) decreases when the stabilizing system (100) expands along the longitudinal axis.

A sampling-by-pushing system includes a setting-by-pushing mechanism and a centralizing device. The setting-by-pushing mechanism is connected with the centralizing device through a connecting pipe, and is configured to be set and sealed in a borehole. The centralizing device includes a base body and a retractable support arm arranged on the base body. The support arm is configured to be in contact with the wall of the borehole so as to position the setting-by-pushing mechanism in the center of the borehole.

Drilling tools are frequently subject to rotation with respect to the central drilling axis caused by torque. A mechanical linkage can be configured to apply force that is proportional to the weight-on-bit on the borehole surface while transmitting axial loads used to generate weight-on-bit. The device can be used to manage drill string twist that could lead to drilling dysfunctions.

A core detection device of a coring instrument includes a base body and a core switch mechanism provided on the base body. The base body is provided with a core channel communicated with a core barrel. The core switch mechanism includes a detection portion, a connecting rod assembly and a travel switch which are sequentially arranged and connected along a length direction of the coring instrument. The detection portion is rotatably installed on the base body and one end thereof is extended into the core channel, so that a core passing through the core channel pushes the detection portion to rotate. The connecting rod assembly can be pulled by the rotating detection portion to trigger the travel switch to operate. The core switch mechanism adopts a slider-connecting rod structure, and the kinematic pairs are mainly a sliding pair and a rotating pair.

A centralizing perforating gun for perforating a tubular in a wellbore include a gun housing, perforating charges positioned within the gun housing and detonatable to perforate the tubular, and a centralizing system. The centralizing system includes an extendable member configured to move between a retracted position and an extended position. The extendable member is configured to engage a surface of the tubular in the extended position, thereby biasing the centralizing perforating gun away from the surface of the tubular.

A perforation system includes: a perforating tool including a main body and a perforating head disposed within the main body; a wireline electrically coupled to the perforating head; a pulse generator electrically coupled to the wireline; and a power supply electrically coupled to the pulse generator. Upon electrification of the perforating head, a spark discharged from the perforating head arcs to a perforation target location.

An in-pipe apparatus for pipe inspection or maintenance is provided. The apparatus includes: a rotational deployment mechanism to rotationally deploy a probe or tool about an inner circumference of a pipe with respect to an axis of rotation; a radial deployment mechanism to radially deploy the probe or tool in a radial direction from the axis of rotation toward a target point on the inner circumference of the pipe; and a passive centering mechanism to passively align the axis of rotation with the axis of the pipe. In some embodiments, the rotational deployment mechanism includes a motor to rotate the radial deployment mechanism about the axis of rotation. In some embodiments, the apparatus further includes a longitudinal deployment mechanism to longitudinally deploy the probe or tool along the axis of the pipe, with the passive centering mechanism passively maintaining alignment of the axis of rotation with the pipe axis during the longitudinal deployment.

A downhole tool that has a plurality of arm assemblies. Each of the arm assemblies has an arm configured to expand and retract and an actuator. A hydraulic bus in fluid communication with the plurality of arm assemblies. A plurality of flow control devices. The flow control devices are configured to selectively isolate one or more arm assemblies of the plurality of arm assemblies from the hydraulic bus while maintaining the other arm assemblies of the plurality of arm assemblies in communication with the hydraulic bus.