Research On Inferior Defect-detection Techniques Of Carbon Electrode

The traditional detection technique in the carbon industry mainly depends on the examiner experience lever. By beating the carbon electrode using a hammer, the examiner can recognize whether or not there existing inferior defects through the sounds. Diagnostic test accuracy of this method, connected with the experience, ability, working attitude and maneuvering stability, is difficult to be normalized. Because of its depending on individual behaviors, a certain proportion of misjudgments can be generated. Therefore, some defective goods enter the next procedure and directly influence the product yield and performance indicators.This paper, by reviewing some related documents, and in combination with the experience of other industry products internal defects detection, summarizes several inferior defect-detection techniques for carbon electrode. By the continual testing of the researcher, making specifically presents two methods of those techniques. One is ultrasonic method and the other is impact hammering method. The detection efficiency is significantly improved by setting up an automatic test platform integrating these two methods. Based on a large quantity of sample experiments and manufacture practice, qualitative analysis of the defects can be implemented. The ultrasonic method utilizes non-metallic ultrasonic to assess the internal quality of the carbon electrode on the basis of the ultrasonic propagation velocity in the electrode. The impact hammering method, however, mainly depends on the relevance between the sound characteristic and electrode quality. Frequency of the sound wave is defined as characteristic quality for pattern recognition. What’s more, this paper also discusses the application of software MATLAB to the audio signal process, including filtering and denoising. The detection accuracy can be significantly increased by the combination of the above two methods.This paper, on the basis of numerous experiment data and a database written in VC++, lays a foundation for the internal quality-test system of the carbon electrode.