Description
This webinar covers measurement variability due to surface
roughness, geometry, and human operators in wet magnetic particle inspection (MPI)
of metal castings. Steel castings have rougher surfaces than machined parts, which
makes this an important factor to investigate because unevenness on the surface
causes the particles to collect and may result in false positives or prevent the
human operator from finding true defects. An advantage of castings is their complex
geometries; however, this geometry creates a variance in the magnetic field strength
on the part. If a process is not properly set up to account for the effect of geometry
on the magnetic field strength, the discontinuities may not be identified in regions
where the magnetic field strength is low. Lastly, a gauge repeatability and reproducibility
(R&R) study was performed in three foundries to investigate the human error
in wet MPI. The R&R results were reported as the “percent of matches.”
Key takeaways:
- Understand the effects of surface roughness on the effectiveness of wet MPI
- Understand the effects of geometry on the magnetic field strength
- Understand the current percent match gauge R&R results for wet MPI in metal castings