The invention relates to an acoustic sensor system (1) for detecting a defect (2) of a pipeline wall (3), having: at least one transmitter unit (4) which is configured to emit ultrasound in the direction of a pipeline wall (3) and detect an ultrasound echo reflected by the pipeline wall (3); and a control unit (5) which is connected to the at least one transmitter unit (4) for signaling purposes and which is configured to detect a defect (2) of the pipeline wall (3) using a present change in he ultrasound echo. The invention additionally relates to an in-line inspection device comprising the sensor system (1), to a method for detecting a defect (2) in a pipeline wall (3), to a computer program, to a data carrier signal, and to a data storage unit.

An AE-signal detecting device for an abrasive wheel includes: an AE sensor which outputs an AE signal upon receipt of an elastic wave generated in an annular abrasive wheel sandwiched between a fixed flange fixed to a rotating shaft and a movable flange provided capable of getting closer to/separating from the fixed flange; a transmission circuit portion which wirelessly transmits the AE signal output from the AE sensor; and a reception circuit portion which receives the AE signal transmitted wirelessly, wherein the AE sensor is disposed on the movable flange or the fixed flange, detects the elastic wave transmitted from the abrasive wheel, and outputs the AE signal.

An apparatus and a method for inspecting a semiconductor includes a water tank which includes a housing, an interior of which is filled with a liquid, and a support block which provides a settling surface for an inspection object inside the housing. A plurality of signal generators are installed on a bottom surface of the housing, and output a frequency signal in a direction in which the inspection object is located. A power supply operates the signal generators. A probe is placed above the inspection object, and a receiver which operates with the probe and is attached to a bottom surface of the support block. Foreign matter remaining on the inspection object are removed, using a plurality of frequency signals which are output by the plurality of signal generating units.

A method of testing for thickness loss in a metal wall is disclosed. The method includes mounting a first and a second ultrasonic transducer to the metal such that the transducers are in ultrasonic communication along a beam line and moving the first and second ultrasonic transducers along a scan line. A series of composites of received signal measurements are obtained by, at multiple locations along the scan line, using the first ultrasonic transducer to transmit ultrasonic signals through the metal wall along the beam line at a plurality of transmission angles and obtaining composites of received signal amplitudes by combining signal amplitudes measured by the second ultrasonic transducer. The series of composites are input into a predetermined relationship to obtain a thickness profile indicative of a proportion of remaining wall thickness. The predetermined relationship is experimentally obtained to characterize a given metal wall of nominal thickness.

Method for monitoring the operation of a pair of turboprop engines of an aircraft comprising the steps of: detecting the sound pressure generated by the first or second turboprop engine generating a respective first or second signal x(t); iteratively calculating by means of a function Rx/Ry the similarity between the first/second signal x(t)/y(t) at a time T1 and at a time T2 subsequent to time T1; and storing the degrees of similarity calculated in successive iterations in order to detect situations of normal operation of the engines when the degrees of similarity fall in successive iterations within the interval of a first value and to detect a potential fault situation in the engines when the degrees of similarity depart from this interval.

A method of determining wear/degradation levels of a consumable assembly of a welding/plasma torch may utilize a controlled sound signal in order to determine an acoustic profile or full spectral audio analysis dataset of the consumable assembly that facilitate the identification of patterns that correlate to certain wear/degradation levels of the consumable assembly. The full spectral audio analysis dataset may be obtained by subjecting a given consumable assembly to a controlled sound signal between operations and as the consumable assembly degrades over time. The full spectral audio analysis may serve as a wear/degradation profile over the life of the given consumable assembly. With a full dataset known for a particular consumable assembly model, an acoustic profile of another consumable assembly of the same model may be obtained and compared to the full dataset in order to identify the wear/degradation level of the tested consumable assembly.

In one example, a method performed by electronic circuitry comprises: causing a transducer to transmit a first signal; receiving a second signal from the transducer; computing distances responsive to a time between the first and second signals; determining a vibration characteristic based on the distances; reading reference vibration characteristics from data in a memory; comparing the input vibration characteristic to the reference vibration characteristics; and responsive to the comparing, performing at least one of: providing a signal representing a status of the comparing; or updating the data in the memory.

Methods and devices are provided for analyzing a tubular structure including at least two electromagnetic-acoustic transducers (EMAT) and, called sensors, attachable or attached in, on or in the vicinity of the tubular structure; and computation and/or memory resources, that are accessed locally and/or remotely and that are configured to determine, for the pair of sensors, a function representing the impulse response of the tubular structure on the basis of the diffuse acousto-elastic noise present in the structure. Developments describe the use of rings supporting the sensors; translation and/or rotation movements; permanent or temporary installations; hinged rings; various computation modes, e.g., intercorrelation, a passive inverse filter, or correlation of the coda of the correlation; the use of artificial noise sources, imaging (e.g., tomography) for determining the existence of one or more defects in the structure. Software aspects are described.

A method of monitoring both liner wear and charge impact in an industrial mill uses a sensor mounted on an elongated element deployed through a shell into a liner of the mill. The elongated element wears at a same rate as the liner under conditions within the shell. Liner wear is related to a reduction in length of the elongated element as measured by travel time of an ultrasound wave, while location and strength of charge impact is related to change in amplitude of vibrations caused by the charge impact. Liner wear measurement can be improved by using shear ultrasound waves instead of conventional longitudinal ultrasound waves. A mill monitoring apparatus has a means for acquiring ultrasonic waves and audible sound waves using the same digitizer; a means for determining the angular position of the monitoring apparatus; and a means for supplying electric power to the apparatus.

A sonic speed measurement device includes a reception array in which a plurality of reception elements which output reception signals in response to reception of an ultrasonic wave are disposed in one direction, a phase difference detection portion that detects a phase difference between the reception signals output from the reception elements adjacent to each other in a case where the plurality of reception elements receive the ultrasonic wave which propagates in a spherical wave shape from a target point, and a sonic speed calculation portion that calculates a sonic speed of the ultrasonic wave on the basis of the phase difference.