Methods and systems for damping torsional oscillations of downhole systems are described. The systems include a downhole string, a bit support assembly configured to support and receive a disintegration device, wherein the disintegration device is disposed on an end of the downhole string and mounted to the bit support assembly, and a damping system configured at least one of on and in the bit support assembly, the damping system comprising at least one damper element arranged in contact with a portion of the bit support assembly.

Methods and systems for damping torsional oscillations of downhole systems are described. The systems include a downhole string, a bit support assembly configured to support and receive a disintegration device, wherein the disintegration device is disposed on an end of the downhole string and mounted to the bit support assembly, and a damping system configured at least one of on and in the bit support assembly, the damping system comprising at least one damper element arranged in contact with a portion of the bit support assembly.

A method for calibrating an output of a torsional vibration transducer can include: providing a torsional vibration transducer proximate to a body of a shaft configured to rotate along an axis of rotation, the torsional vibration transducer configured to measure a torsional vibration of the shaft; actuating the shaft to cause rotation of the shaft; while the shaft rotates, acquiring, using the torsional vibration transducer, a plurality of zero-stress measurements of the shaft across a plurality of gaps between the torsional vibration transducer and the shaft; calculating at least one calibration coefficient using the plurality of zero-stress measurements; and calibrating the output of the torsional vibration transducer according to the at least one calibration coefficient to reduce a sensitivity of the torsional vibration transducer to changes in gap between the torsional vibration transducer and the shaft when the torsional vibration of the shaft is measured.

A method for calibrating an output of a torsional vibration transducer can include: providing a torsional vibration transducer proximate to a body of a shaft configured to rotate along an axis of rotation, the torsional vibration transducer configured to measure a torsional vibration of the shaft; actuating the shaft to cause rotation of the shaft; while the shaft rotates, acquiring, using the torsional vibration transducer, a plurality of zero-stress measurements of the shaft across a plurality of gaps between the torsional vibration transducer and the shaft; calculating at least one calibration coefficient using the plurality of zero-stress measurements; and calibrating the output of the torsional vibration transducer according to the at least one calibration coefficient to reduce a sensitivity of the torsional vibration transducer to changes in gap between the torsional vibration transducer and the shaft when the torsional vibration of the shaft is measured.

A method includes receiving data characterizing time-dependent lateral vibration of a shaft of a machine, the lateral vibration indicative of motion of at least a portion of the shaft perpendicular to a first direction. The lateral vibration is detected by a first sensor located at a first predetermined location on the shaft. The method further includes, receiving data characterizing time-dependent torsional vibration of the shaft, the torsional vibration indicative of rotation of the shaft around the first direction. The torsional vibration is detected by a second sensor located at a second predetermined location on the shaft. The method also includes calculating a coherence of the data characterizing time-dependent lateral vibration and the data characterizing time-dependent torsional vibration. The method further includes identifying, based on the coherence, a first frequency value in the frequency domain indicative of coupling between the time-dependent lateral vibration and the time-dependent torsional vibration.

The invention relates to a wave-emitting device comprising an electromechanical actuator stimulated by a signal generator that allows it to generate torsional waves with a higher amplitude, and to an ultrasonic transducer comprising said device. The use of said devices allows the reconstruction of the structural characteristics of the materials subject to the waves generated by the emitter device.

The invention relates to a wave-emitting device comprising an electromechanical actuator stimulated by a signal generator that allows it to generate torsional waves with a higher amplitude, and to an ultrasonic transducer comprising said device. The use of said devices allows the reconstruction of the structural characteristics of the materials subject to the waves generated by the emitter device.

Embodiments of the present disclosure relate to a tangible, non-transitory, computer-readable medium that stores instructions executable by one or more processors, in which the instructions cause the one or more processors to determine a threshold value associated with an axial acceleration oscillation amplitude at a drill bit, in which the drill bit is a part of a drilling system. The instructions further cause the one or more processors to receive an operating parameter value of the drilling system, compare the operating parameter value with the threshold value, and adjust an operation of the drilling system in response to comparing the operating parameter value with the threshold value.

Embodiments of the present disclosure relate to a tangible, non-transitory, computer-readable medium that stores instructions executable by one or more processors, in which the instructions cause the one or more processors to determine a threshold value associated with an axial acceleration oscillation amplitude at a drill bit, in which the drill bit is a part of a drilling system. The instructions further cause the one or more processors to receive an operating parameter value of the drilling system, compare the operating parameter value with the threshold value, and adjust an operation of the drilling system in response to comparing the operating parameter value with the threshold value.

A method of bearing fault detection including measuring a signal of torsional energy transfer from a rotating device to a non-rotating device at a distance away from the rotating device, calculating a health status of the rotating device based on a comparison of the measured signal to a baseline signal, and calculating a remaining useful life of the rotating device.