Abstract:
The present invention relates to a method for detecting temporally varying thermomechanical stresses and/or stress gradients over the wall thickness of metal bodies, in particular pipelines. In the method, the temperature on the outer surface of the body is measured in order to determine a temperature progression and stress progression therefrom. In addition, electromagnetic ultrasonic transducers are used at at least one measuring point on the outer surface in order to determine the progression of the stresses and/or stress gradients over time over the wall thickness of the body in conjunction with the result of the temperature measurement. The method allows the fatigue monitoring of pipelines even in the event of rapid stress changes.
Abstract:
An X-ray stress measuring apparatus, for measuring stress on a sample, comprises: a pair of X-ray generating means (10, 11, 10′, 11′) for irradiating X-ray beams, determining an angle defined between the X-ray beams, mutually, at an arbitrary fixed angle, on a plane inclining by an angle desired with respect to a surface of the sample to be measured stress thereon; an X-ray sensor portion (29) for detecting plural numbers of Debye rings (C, C′), which are generated by incident X-ray beams from said pair of X-ray generating means; and a battery (410) for supplying necessary electricity to each of parts of the apparatus, wherein said X-ray sensor portion is made up with only one (1) piece of a 2-dimensional X-ray detector (20) or a 1-dimensional X-ray detector (20′), and is disposed in a position where the plural numbers of Debye rings generated by the incident X-ray beams from the at least one pair of X-ray generating means are adjacent to each other, or intersect with each other, thereby detecting the plural numbers of the Debye rings caused due to the X-ray and the X′-ray in common with.
Abstract:
A system and methods with which changes in microstructure properties such as grain size, grain elongation, texture, and porosity of materials can be determined and monitored over time to assess conditions such as stress and defects. An example system includes a number of ultrasonic transducers configured to transmit ultrasonic waves towards a target region on a specimen, a voltage source configured to excite the first and second ultrasonic transducers, and a processor configured to determine one or more properties of the specimen.
Abstract:
A device for determining a bearing preload of a rolling-element bearing includes an exciter configured to be attachable to a component of the rolling-element bearing and to excite the component of the rolling-element bearing and cause it to vibrate when the rolling-element bearing is not rotating, at least one vibration sensor configured to be attachable to the component or to a further component of the rolling-element bearing and to record (capture) a mechanical reaction, in response to the excitation, of the component or the further component of the rolling-element bearing, and an evaluating circuit configured to receive the sensor signal and provide an evaluation signal based on the sensor signal, the evaluation signal including information about the bearing preload. An associated method and computer program are also disclosed.
Abstract:
At least one embodiment is directed to a sensor for measuring a parameter. A signal path of the system comprises an amplifier (612), a sensor element, and an amplifier (620). The sensor element comprises a transducer (4), a waveguide (5), and a transducer (30). A parameter such as force or pressure applied to the sensor element can change the length of waveguide (5). A pulsed energy wave is emitted by the transducer (4) into the waveguide (5) at a first location. The transducer (30) is responsive pulsed energy waves at a second location of the waveguide (5). The transit time of each pulsed energy wave is measured. The transit time corresponds to the pressure or force applied to the sensor element.
Abstract:
A system is provided for both reading an optical identification mark, such as a bar code, on a fastener and for making ultrasonic load measurements in the fastener using a single probe for use during fastener installation with assembly tools and for the inspection of load in preinstalled fasteners. The probe includes both a fiber optic imaging cable and at least one electrical conductor. The fiber optic imaging cable is optically coupled to an imaging device such as a bar code reader allowing the bar code reader to be located remote from the fastener. The electrical conductor provides an electrical connection from the ultrasonic transducer on the fastener to load measurement instrumentation. The probe is further capable of providing illumination of the bar code to facilitate reading of the bar code.
Abstract:
At least one embodiment is directed to a sensor for measuring a parameter. A signal path of the system comprises an amplifier (612), a sensor element, and an amplifier (620). The sensor element comprises a transducer (4), a waveguide (5), and a transducer (30). A parameter such as force or pressure applied to the sensor element can change the length of waveguide (5). A pulsed energy wave is emitted by the transducer (4) into the waveguide (5) at a first location. The transducer (30) is responsive pulsed energy waves at a second location of the waveguide (5). The transit time of each pulsed energy wave is measured. The transit time corresponds to the pressure or force applied to the sensor element.
Abstract:
The present invention is directed to a system and methods with which changes in rail conditions can be determined and monitored over time. The present invention includes a database of data, wherein a first set of data is used for comparison with a second set of data to determine the stress state of rail.
Abstract:
A force sensor having a substrate for measuring forces is provided, on which substrate a first path and a second path for travel of acoustic surface waves are arranged. The two paths are arranged essentially parallel to one another and their lengths are different. An effect of a force on the substrate is detectable by measuring a time needed for an acoustic surface wave to travel at least one of the first and second paths.
Abstract:
A method for stimulating a sensor and measuring it's output over a frequency ranges starting at a frequency f1 and ending at a frequency f2 is disclosed, which can include the following steps: (a) placing an assembled sensor on a shaker table; (b) setting the shaker table at a specified frequency and exciting the sensor by moving the sensor up and down at an amplitude at least approximately equal to a reference “g” level of acceleration; (c) measuring the sensor's output and recording the measured output as a first value; (d) incrementally changing an excitation frequency of the shaker table and adjusting the amplitude to achieve the reference “g” level; (e) measuring the sensor's output and recording the measured output as a second value; and (f) repeating steps (d) and (e) for one or more discrete frequencies within the frequency range to provide a frequency response curve for the sensor over the frequency range.