1. Make sure to check the machine regularly;
2. The operator needs to understand the performance characteristics of the eddy current flaw detector, various buttons, operating methods and precautions;
3. After using the eddy current flaw detector, the connecting cables should be neatly arranged. At the same time, turn off the power switch and unplug the power cord. The instrument, connecting cables and probes should also be cleaned and placed neatly in the toolbox.
1. Blind area
The small distance from the detection surface to the defect that can be found is called the blind zone. Defects in the blind zone cannot be found at all. The blind zone is related to the blocking time of the amplifier and the initial pulse width. The blocking time is long, the initial pulse is wide, and the blind zone is large.
The ability to distinguish two adjacent defects with different distances on the phosphor screen is called resolution. The smaller the distance between the two defects that can be distinguished, the higher the resolution. The resolution is related to the pulse width. The pulse width is small and the resolution is high.
3. Sensitivity margin
Sensitivity margin refers to the ability to find small defects within a certain detection range after the combination of the eddy current testing machine and the probe. Specifically, when the specified wave height is obtained from an artificial test block with a specified ranging aperture, the high dB number reserved by the instrument indicates a high sensitivity margin.
As a portable non-destructive testing instrument, the eddy current flaw detector is widely used in steel structure, pressure vessel, pressure-bearing pipeline weld and plate, casting, forging and other overall material testing. It can be used to quickly and accurately determine the weld, and the distribution of crack defects on the surface of the material and the shallow surface.