Influence of Air Gap on Magnetic Particle Testing in Thin Ring Open Parts

According to the problem that the air gap in the thin annular opening parts was to affect the magnetization detection, the factors affecting the magnetic field strength were found out. Taking the magnetic particle testing of the product of ring parts as an example,test results showed that the air gap increased the magnetic reluctance, produced a more magnetic pressure drop in the gap and resulted in the lack of magnetization, which made some minor defects difficult to be detected very well.