GB/T 35393-2017Non-destructive testing—Practice for electromagnetic (eddy-current) sorting of nonferrous metals (English PDF)

4.1 General

Electromagnetic separation is mainly used absolute (single) coil method and comparative (double) coil method, usually based on experience to choose detection methods. Absolutely

In the Coil method (pass-through or drop-in), the instrument is calibrated by testing a control block of known electrical characteristics. Detected with alloy, hot

Processing or hardness-related electrical parameter values are displayed on the instrument. In the comparative coil method (through or placed), two wires are used

Circle to be seized compared to the workpiece and the test block, in order to determine whether the inspection of the workpiece is qualified.

4.2 sorting method

4.2.1 absolute coil method

4.2.1.1 Through the coil method

Will be different contrast test blocks in turn into the detection coil, adjust the instrument to obtain the appropriate signal. Usually use 3 respectively on behalf of the file, mid-range

And the next level of contrast test block calibration. Then the workpiece to be seized into the detection coil, observe the signal, sorting.

4.2.1.2 placed coil method

Place the lay-in coils in turn on the contrast test block and adjust the instrument to obtain the appropriate signal (see 4.2.1.1). Then place the coil on it

Check the workpiece, observe the signal, sorting.