SU849065A1 - Method of systematic error detection in ultrasonic oscillation propagation time counters - Google Patents

Description

The invention relates to kontrolnoizmeritelnoy the art and may be used to control the physical-mechanical properties of construction and other materials on the propagation time of the ultrasonic 'k'olebany in stro- ⁵ itelstve, power and other industries.

A known method for detecting the systematic error of time meters • 10 of the propagation of ultrasonic vibrations in solid media is that elastic vibrations are excited in the main sample and their propagation time is measured, then the same is carried out on an additional sample, the size of which is different, and the acoustic properties coincide with the properties of the main sample

The magnitude of the systematic error * · ^ ti is determined from the expression (Λ-t

where, is the arithmetic mean value of the propagation time of ultrasonic vibrations, respectively, · in smaller and larger samples;

C - acoustic bases of a smaller and larger sample, respectively.

The disadvantages of this method are the low accuracy of error detection due to the difficulty of choosing two samples with identical acoustic properties, and the existence of a measurement error associated with the electronic unit and the exact installation of the transducers. In addition, a rather long measurement time is inherent in this method, since it is necessary to take samples, measure their geometric dimensions with a given accuracy, and only then take measurements.

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The purpose of the invention is to reduce the time for detecting errors and improve accuracy.

This goal is achieved by the fact that after measuring time, an additional, arbitrary size is attached to the main sample, and oscillations are excited in this composite sample and their propagation time is measured, and the systematic error is judged by the difference in the times of the meter readings and the error value obtained by calculation.

The method is as follows. fifteen

It excites vibrations and measures the speed of their propagation in the main sample, calculates the arithmetic mean value of time C using the formula t ^ = t ^ _n + fi, ²⁰ ₍ where t is the true propagation time of ultrasound in the sample;

Δ. - the value of the systematic error of the meter. Then, to the basic pattern accession nyayut additional ²⁵ which may differ from both the core properties and size. In the obtained composite sample, measurements similar to the above are carried out and the arithmetic mean value of time t is calculated by the formula

Ch = Chn ⁺ Chi ^{+ A} 'where t ^ _n “is the true time of propagation of the ultrasound phenomenon in an additional sample.

The true ultrasound propagation time in the additional sample will be 40

By adjusting the zero settings of the meter, they achieve the equality of the calculated value and the readings of the time meter of the additional sample.

The invention improves the metrological, the provision of measuring instruments for the speed (time) of the propagation of ultrasound, not only during the release of devices, but also due to the reduction of the systematic measurement error when controlling the physicomechanical properties of building and structural materials, increases the reproducibility and reliability of the measurement results, which, ultimately, improves the quality of products and designs.

Claims (1)

The purpose of the invention is to reduce the time of error detection and increase accuracy. This goal is achieved by adding an additional, arbitrary 1) GC dimensions to the main sample after the time measurement, and in this composite sample, oscillations are excited and their propagation time is measured, and the systematic error is measured using the calculated time difference. by the magnitude of the error. The method is carried out in the following manner. I excite F-oscillations and measure their speed in the axes -. The arithmetic mean time value {n by the formula i 1n (where t is the true propagation time of ultrasound in the sample) is the systematic error of the meter. Then, the additional sample is attached to the main sample, which may differ from the main one as by property Similarly by size In the obtained composite sample, similar measurements are made above and the arithmetic average time t is calculated and the formula is true for the total spread t of ultrasound in addition m sample. The true propagation time of ultrasound in an additional 1 T sample will be equal to the Regulator with the meter zero settings, achieving equality of the calculated value of t ,, and the readings of the time meter of the additional sample. The invention improves metrological, providing the meters with the speed of ultrasound propagation the production of devices, but also of operation by reducing the systematic error of measurements when monitoring the physical and mechanical properties of building and construction materials c, increases the reproducibility and reliability of measurement results, which ultimately improves the quality of products and structures. Claims A method for detecting the systematic error of measuring the time of propagation of ultrasonic vibrations in solid media, which consists in the fact that elastic oscillations are excited in the main sample and measure their propagation time, characterized in that, in order to reduce the error time of the error and improve accuracy After measuring the time, an additional, arbitrary size is attached to the main sample, and in this composite sample a vibration is excited and the time of their propagation is measured, and ematicheskoy error is judged from the difference in time meter readings and values obtained by calculation errors. Sources of information taken into account in the examination 1. USSR Author's Certificate No. 405067, cl. G 01 N 29/04, 1973 (liptotype).