On-line dynamic real-time monitoring method and apparatus for magnetic suspension concentration

Abstract

The invention discloses an on-line dynamic real-time monitoring method and an apparatus for magnetic suspension concentration, the designed on-line real-time monitoring apparatus for the magnetic suspension concentration comprises a tubular type electromagnetic sensor, a sensor cable, two adapter rings, an electromagnetic detector and two standard magnetic suspension concentration calibration test tubes; the tubular type electromagnetic sensor comprises an external electromagnetic detection coil, a nonmetal circular pipe and a metal shield pipe; the method is characterized in that a pulse transient alternate electromagnetic field is used for motivating the magnetic powder in a constant capacity (100ml) magnetic suspension, a secondary reflection magnetic field generated by the magnetic powder is received, the electromagnetic detector memories the characteristic signals, when the concentration value of the magnetic suspension to be detected exceeds an allowed scope, the electromagnetic detector enables real time alarm, thereby the magnetic suspension concentration changes which are caused by various reasons of nonuniform stirring, impurity containing and repeated usage and the like can be timely found, the detection leakage, misjudgment and repeated detection work are avoided, and the detection quality of the magnetic powder can be effectively enhanced.

Description

technical field [0001] The invention relates to a non-destructive detection technology, in particular to an online dynamic real-time monitoring method and device for the concentration of a magnetic suspension. Background technique [0002] Magnetic particle testing is a non-destructive testing method that uses magnetic phenomena to detect surface and near-surface defects of ferromagnetic materials. At present, magnetic particle inspection is mainly based on wet inspection, mainly using oil-based carrier liquid or water-based carrier liquid as a dispersant, configured as a magnetic suspension, and then applied to the surface of the workpiece, the leakage magnetic field absorbs the magnetic powder to form magnetic marks to show the existence of defects and shape. The concentration of the magnetic suspension directly affects the detection sensitivity. If the concentration is too low, the magnetic marks are very weak and difficult to recognize visually; if the concentration is ...

AI Technical Summary

Problems solved by technology

In order to ensure that the concentration of the magnetic suspension is maintained within the standard concentration range of the magnetic suspension, the concentration of the magnetic suspension needs to be checked before the start of the detection work. Usually, the sedimentation tube measurement method is used, which requires demagnetization, precipitation, and visual reading of the magnetic powder. The concentration value of the measured magnetic suspension can be obtained from the precipitation height. This measurement method takes a long time and the measurement accuracy is not high.

At the same time, the above-mentioned determination method can only be carried out before the detection. During the detection process, when the concentration of the magnetic suspension changes due to various reasons such as uneven stirring, impurities, and repeated use, it cannot be found in time.

As a result, it will directly affect the clarity of detected defects, leading to misjudgment and affecting the quality of inspection

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