A device for detecting micro-cracks near the surface of pressure-bearing equipment

Abstract

The invention relates to a near-surface micro crack detection device of pressure equipment. The near-surface micro crack detection device is characterized by consisting of a signal generator (1), a power amplifier (2), a magnetic yoke (3), an excitation coil (4), a first horizontal detection coil (5), a second horizontal detection coil (6), a vertical detection coil (7) and an oscilloscope (8), wherein the number of turns of the excitation coil (4) is 30, and the diameter of the excitation coil (4) is 15-20mm; the signal generator (1) generates a sinusoidal signal, and the sinusoidal signal is amplified by the power amplifier (2) to generate distribution of magnetic lines in the space through the excitation coil (4); the magnetic lines (10) overflow via a near-surface defect of pressure equipment (9); the first horizontal detection coil (5) is used for detecting the global magnetic field tangential component, the second horizontal detection coil (6) is used for detecting the local magnetic field tangential component, the vertical detection coil (7) is used for detecting the depth information of the defect, and a detection signal is displayed by the oscilloscope (8). The near-surface micro crack detection device has the advantages that the different detection coils are used for detecting the information of different sizes of defects, the detection accuracy of size parameter of the defect is improved, the operability is high, the innovation is good, and the near-surface micro crack detection device can be applied to various types of physical engineering.

Description

technical field [0001] The utility model relates to a device for detecting tiny cracks near the surface of pressure equipment, which belongs to the field of electromagnetic nondestructive testing. Background technique [0002] Boilers, pressure vessels, and pressure pipes are pressure-bearing special equipment, and most of these equipment are made of some metal materials. Corrosion and thinning of metal materials and cracking at stress-concentrated parts are often the main safety hazards of these pressure-bearing special equipment, so early detection of these defects is of great significance. [0003] Existing detection technologies have certain limitations. For example, the penetrant detection technology is affected by temperature, and the surface of the workpiece must be pre-treated, and the detection process is cumbersome; the magnetic particle detection technology must be pre-treated on the workpiece surface, which may cause certain damage to the workpiece during detecti...

AI Technical Summary

Problems solved by technology

[0004] The current magnetic flux leakage detection sensors are often used for a single purpose, and all the information of the defect is detected through the same sensor

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