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一、前言由于焊缝的特点,超声焊缝探伤有别于一般的探伤。首先焊缝存在加强部分,使得在1/2S(即一次波)探伤时探头无法前移,存在声束不能达到的区域。同时管道只能单面探伤,对中上部焊缝需用1S(二次波)探伤。因此须考虑管壁曲率的影响。另外还因焊缝本身的高衰减特性,不能以常用的距离——振辐曲线〈下称DAC图表〉来定量,需对曲面和焊缝的影响进行修正后,才可用它。本文还对缺陷长度和深度测量方法等问题进行了探讨。
First, the preface Due to the characteristics of the weld, ultrasonic weld inspection is different from the general inspection. First of all, there is a strengthening part of the weld so that the probe can not move forward when the 1 / 2S (primary wave) flaw detection exists, and there is an area that the sound beam can not reach. At the same time the pipeline can only be single flaw detection, the upper weld required 1S (secondary wave) flaw detection. Therefore, we must consider the influence of wall curvature. In addition, due to the high attenuation characteristic of the weld itself, it can not be quantified by the commonly used distance-vibration curve (DAC chart). It is necessary to correct the influence of the surface and the weld before it is used. This article also discusses the defect length and depth measurement methods and other issues.