Rail tread crack ultrasonic detection device and detecting method

Abstract

The invention provides an ultrasonic detecting device and a detecting method for inclined cracks on a steel trail pedaling surface. The detecting device of the invention uses a detecting probe of the invention and a common signal processor in a whole for judging whether the inclined cracks on a steel trail pedaling surface exceeds the specific threshold value. The detecting probe of the invention comprises two independent probes encapsulated together for carrying and convenient use. The detecting method of the invention combines the detecting probe of the invention with the common signal processor to rapidly judge whether the crack depth of the surface opening is higher than the specific threshold value (for example 5 mm).

Description

technical field [0001] The invention relates to an ultrasonic detection device and a detection method, in particular to an ultrasonic detection device and a detection method for rail tread cracks. Background technique [0002] In recent years, with the large-scale speed increase of my country's railways, the running speed and load capacity of trains have been greatly improved, which has led to new forms of rail defects, and a large number of oblique cracks on rail treads have appeared on some lines According to the survey statistics, the average distance between oblique cracks is 41mm, and the larger one reaches 160mm. The cracks generally develop obliquely downward in the direction of 15°-30° with the rail tread. When the crack develops to 6-8mm away from the tread, the crack is almost horizontal. It expands and breaks quickly, so it is best to be able to identify the crack when it grows to about 5mm, so that it will not cause excessive waste and prevent the rail from breakin...

AI Technical Summary

Problems solved by technology

The echo amplitude method for oblique cracks on rail treads has the following disadvantages: (1) oblique cracks seriously affect the incidence of sound waves, thereby affecting the echo height and quantitative accuracy; (2) the echo amplitude method can only be quantified according to the echo The range of the crack depth is roughly given, but the specific depth of the crack cannot be given; (3) The artificial cracks in the comparison test block used in the echo amplitude method are quite different from the actual cracks, which affects the quantitative accuracy; (4) Since the echo amplitude is affected by many factors, the repeatability of the measurement results is poor

Moreover, this kind of crack is often substantially perpendicular to the rail extension direction or at a certain angle (for example, 15°, 30° or other angles) with the direction perpendicular to the rail, and the traditional flaw detection equipment using TOFD must measure it. Set the scanning direction and probe position angle for each crack individually. In summary, it is not suitable for quick judgment on whether the depth of oblique cracks on rails exceeds the threshold, regardless of cost or efficiency.

[0007] Therefore, the current quantitative method cannot solve the quantitative problem of rail oblique cracks well, and cannot make an accurate evaluation of rail oblique cracks.

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