Method and instrument capable of accurately measuring thickness of ultrathin workpieces

Abstract

The invention provides a method capable of accurately measuring the thickness of ultrathin workpieces. As the ultrasonic information representing workpiece thickness is extracted by adopting a signal processing method, the invention is suitable for the ultrasonic thickness measurement technique for both ultrathin large-curvature workpieces and common workpieces, and the core of the invention is to perform fast Fourier transform on received echo signals so as to obtain measurement results. An instrument using the method capable of accurately measuring the thickness of ultrathin workpieces consists of a probe part and a host computer part, wherein the host computer part comprises a DSP control module, an ultrasonic transmitting circuit, an ultrasonic signal-receiving circuit, a signal amplification circuit, a gate circuit, a communication interface, an LCD display and a keyboard. The invention has the advantages of suitability for the thickness measurement of both ultrathin large-curvature workpieces and common workpieces, capability of acquiring ultrasonic echo signals in real time, real-time fast Fourier transform, real-time calculation and storage of pipe wall thickness and capability of realizing mechanized automatic measurement.

Description

technical field [0001] The invention relates to the field of non-destructive testing, and in particular provides a method and an instrument capable of accurately measuring the thickness of ultra-thin workpieces. Background technique [0002] Ultrasonic thickness measurement technology is an important part of the field of non-destructive testing technology, widely used in various fields such as petroleum, chemical industry, metallurgy, shipbuilding, aviation, and aerospace. The existing ultrasonic thickness gauges at home and abroad are based on the principle of ultrasonic pulse reflection to measure thickness. The ultrasonic pulse wave emitted by the ultrasonic probe enters the measured object through the coupling agent, and is reflected when it propagates to the bottom surface in the measured object and is reflected back. The ultrasonic wave (echo) is received by the ultrasonic probe, and the ultrasonic pulse travels back and forth between the two surfaces of the object to ...

AI Technical Summary

Problems solved by technology

When the thickness of the measured object is thin to a certain extent, two adjacent echoes overlap, and the time interval between them cannot be measured, so the thickness of the measured object cannot be obtained.

Due to the large curvature of the workpiece, the ultrasonic reflection echo signal is weak, and the echo series cannot be formed, and the thickness of the workpiece cannot be measured

Therefore, for ultra-thin workpieces, especially ultra-thin workpieces with large curvature, the existing ultrasonic echo instruments are powerless

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