Method for appraising X-ray detection weld joint K value by utilizing overlap joint mark article

Abstract

The invention discloses a method for evaluating a welding seam K value detected by X-ray based on lapping markers, comprising the steps as follows: the lapping marker is arranged at two endpoints of effective evaluation length of a workpiece to be monitored; a central mark is arranged at the central position of the transparent position section of the workpiece to be monitored; subsequently, the welding seam of the workpiece to be monitored is transilluminated so as to obtain the transparent negative of the welding seam of the workpiece to be monitored; on the transparent negative, when the image of a pointer is not coincident to the image which controls a ring, the K value of the photographed negative is qualified; and when the image of the pointer is coincident to the image which controls the ring, the K value of the photographed negative is not qualified. The method solves the problem that in the prior art at home and abroad, whether the photographed welding seam negative meets the requirement or not has no qualitative analysis, thus ensuring the correctness of the negative used for the welding seam detection and analysis. The evaluation method is simple and objective, can be used for judging whether the negative quality evaluation is qualified or not, can be used for judging whether an operator for a ray negative seriously executes the specific process, meanwhile, the negative meeting the requirement evaluated by the method can be directly used for the analysis on the welding seam.

Description

technical field [0001] The invention belongs to the X-ray detection technology of the weld seam quality of boilers or pressure vessels, and in particular relates to a detection method of the X-ray negative film of the weld seam quality. Background technique [0002] The welding quality of boilers, pressure vessels and other equipment is an important guarantee for safe operation. Radiographic flaw detection is one of the inspection methods for detecting internal defects in welding. Radiographic detection is to project a three-dimensional test piece (including the defects) on the film through projection and convert it into a two-dimensional image. Due to the relative position and angle changes between the ray source, the object (including its defects), and the film, the size, shape and position of the image on the negative film will be different from the real object, such as magnification, distortion, overlapping, relative changes in position, etc. The crack is the most dang...

AI Technical Summary

Problems solved by technology

For a long time, in the process of real-time inspection of process operation implementation, and in the evaluation of domestic and foreign X-ray photographic films, there is no technology that can visually inspect whether the transillumination thickness ratio K of the effective section weld meets the standard requirements. If the K value fails to meet the standard requirements, it may cause missed detection of cracks and other hazardous defects

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