Prepare for the Surface Methods - Liquid Penetrant Inspection (LPI) Exam. Utilize flashcards and multiple-choice questions with detailed hints and explanations. Ace your exam with confidence!

Multiple Choice

What was the whiting made with?

In liquid penetrant inspection, whiting is the dry developer that creates a contrasting background and helps pull penetrant out of surface flaws so indications become visible. The traditional whiting is a chalk-like powder, specifically calcium carbonate, suspended in alcohol. The fine chalk particles provide a white coating, and the alcohol carrier allows even application and quick drying, leaving a uniform white deposit that highlights defects when viewed under normal or UV lighting. Other mixtures wouldn’t give that dry, white, uniform background: a calcium carbonate powder in water would stay wet and not provide the same quick-drying film; graphite in oil would create a dark, not white, layer; starch in water would form a paste rather than a fine, dry powder coating.

In liquid penetrant inspection, whiting is the dry developer that creates a contrasting background and helps pull penetrant out of surface flaws so indications become visible. The traditional whiting is a chalk-like powder, specifically calcium carbonate, suspended in alcohol. The fine chalk particles provide a white coating, and the alcohol carrier allows even application and quick drying, leaving a uniform white deposit that highlights defects when viewed under normal or UV lighting.

Other mixtures wouldn’t give that dry, white, uniform background: a calcium carbonate powder in water would stay wet and not provide the same quick-drying film; graphite in oil would create a dark, not white, layer; starch in water would form a paste rather than a fine, dry powder coating.