What is dye penetrant testing (PT) used for in welding inspection?

What is dye penetrant testing (PT) used for in welding inspection?

• A. Detects shallow surface color changes of the weld.
• B. Measures radiographic density of metal.
• C. Detects surface-breaking defects by allowing penetrant to seep into openings and showing voids.
• D. Assesses hardness of weld area.

Answer: (C)

Dye penetrant testing is a non-destructive method that detects surface-breaking defects by using a dye liquid that seeps into any cracks or openings on the weld surface. After removing the excess penetrant and applying a developer, the penetrant trapped in the defects bleeds out to the surface, creating visible indications that show where flaws exist. This makes it ideal for finding cracks, porosity at the surface, and other openings in welds. It won’t reveal subsurface flaws, and it isn’t about color changes, radiographic density, or hardness testing.

Dye penetrant testing is a non-destructive method that detects surface-breaking defects by using a dye liquid that seeps into any cracks or openings on the weld surface. After removing the excess penetrant and applying a developer, the penetrant trapped in the defects bleeds out to the surface, creating visible indications that show where flaws exist. This makes it ideal for finding cracks, porosity at the surface, and other openings in welds. It won’t reveal subsurface flaws, and it isn’t about color changes, radiographic density, or hardness testing.