Which inspections should be used to detect cracks on the bead seat area?

• A. Dye penetrant
• B. Visual
• C. Eddy current
• D. Ultrasonic

Answer: (C)

Detecting cracks in the bead seat area requires a method that is highly sensitive to surface and near-surface flaws in a conductive curved component. Cracks in this region tend to be shallow and open at or very close to the surface, and the bead seat is a complex, rounded area where access is limited. Eddy current inspection uses coils to induce currents in the metal; a crack disrupts those currents, causing a measurable change in impedance as the probe scans around the bead seat. This makes it particularly effective at finding tiny surface-connected cracks quickly without disassembling the wheel or requiring extensive surface prep. Visual inspection can miss cracks hidden by paint or corrosion, dye penetrant needs clean, accessible openings and may be less reliable on tight radii, and ultrasonic can detect subsurface flaws but is more challenging to set up on the bead seat’s curved geometry. So, eddy current is the best-suited method for crack detection in the bead seat area.