Flaw precise positioning method for steel rail ultrasonic flaw detection

Abstract

The invention discloses a flaw precise positioning method for steel rail ultrasonic flaw detection. In the method, a steel rail to be tested is processed into a plate sample of which the thickness is the same as that of the rail waist, a detection route in which the directions of two wheels are vertical is adopted, the central point of a flaw source of the steel rail is determined, and the flaw point is detected and analyzed by a linear cutting method; and thus, an ultrasound probe is in complete fit with the test sample, the detection accuracy is improved, the hit rate and accuracy of the positioning of the central point of the flaw source are increased, detection result offset caused by the offset of the central point is avoided. In addition, the linear cutting mode is used for dissecting the flaw source of the steel rail accurately and the data on the central point of the flaw source and the flaw type can be obtained by further detection and analysis, so an accurate detection basis is provided for improving the quality of the steel rail; and by corresponding control measures, the flaw rate of the steel rail is lowered effectively and the internal quality of the steel rail is assured.

Description

technical field [0001] The invention belongs to the field of rail quality detection, and in particular relates to a method for accurately locating rail defects in ultrasonic flaw detection. Background technique [0002] With the increasing speed of trains and the gradual increase of rail length, the internal quality requirements of rails are getting higher and higher, so the accuracy of rail flaw detection must also be adapted and improved. At present, ultrasonic flaw detection is still commonly used in the detection of internal defects of rails. However, on-line ultrasonic flaw detection of rails can only determine whether the rail meets the corresponding inspection standards, but cannot accurately locate the exact location of the flaw detection defect of the rail. For the determination of the location of the source of damage and the inspection of the type of defect on the rail, it is necessary to use a portable ultrasonic flaw detector to locate the location of the source...

AI Technical Summary

Problems solved by technology

However, due to the small flaw detection defects, the portable flaw detector still has the problem of poor positioning accuracy of the source of damage, and it is often the case that the source of damage cannot be found after offline re-inspection

In particular, because the rail waist has a certain radian and is not a straight line, the ultrasonic probe cannot completely match the measured rail. In addition, the shape and structure of the rail head and rail bottom are complex, resulting in extremely inaccurate flaw detection and location, which in turn leads to defects. Determine the deviation and affect the detection effect of flaw detection

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