Performance of STRESSVISION® indicator based on the principle of measurement of Electro-Motive Forces (EMF), excited in measuring coils of sensor by the magnetic field, initiated by excitation coils in the electromagnetic field of the inspected object. The received signal of the sensor unit is proportional to the difference of the main mechanical stresses (DPMS) at the setup area of sensor on the surface of the monitoring object and in the specified direction.
Probing of metal by special electro-magnetic field enables high reproducibility of indications and to collect information on stress status layer by layer. The measurements provide information sufficient to quantify coefficient of concentration of mechanical stresses CMS, the evaluation of the levels of the difference of the main mechanical stresses DPMS in «direction», the gradient of DPMS and determine the conditions for development of flaw in the examined area of the inspected object.
The process of data collection
- On the surface of the investigated site of the product (control zone) placed a rectangular coordinate grid. The minimum size of the grid is-5 x 5 (lines * columns).
- Grid spacing set depending on the specific issue to be solved, from 5 mm when examining a particular point CMS up to 25 cm in the analysis of stress-strain structures.
- The Probe (Sensor) consistently placed in the nodes (intersections) of a grid zone, maintaining its constant orientation relative to the axes of the products using the pointer (main marker) on the sidelines of the probe.
- Performing point-by-point measurement a.k.a as the “manual scan”
- The received results are preliminary processed in the processor device (the measuring block) and are stored in non-volatile memory.
- After completing the scanning, accumulated results are transfer on laptop or computer where they are stored and for final processing, evaluation and to be represented as cartograms DPMS, CMS, etc.
- Beware of Edge effect during the scanning.