Developers enhance the visibility of penetrant indications by pulling penetrant from a surface open discontinuity and spreading the penetrant through the developer coating on the part surface. The penetrant indication may appear larger than its actual size as the penetrant spreads through the developer over time.
The test surface should be cleaned to remove any dirt, paint, oil, grease or any loose scale that could either keep penetrant out of a defect or cause irrelevant or false indications. Cleaning methods may include solvents, alkaline cleaning steps, vapour degreasing, or media blasting.
Dye penetrant inspection (DP), also called liquid penetrate inspection (LPI) or penetrant testing (PT), is a widely applied and low-cost inspection method used to check surface-breaking defects in all non-porous materials (metals, plastics, or ceramics). The penetrant may be applied to all non-ferrous materials and ferrous materials, although for ferrous components magnetic-particle inspection is often used instead for its subsurface detection capability. LPI is used to detect casting, forging and welding surface defects such as hairline cracks, surface porosity, leaks in new products, and fatigue cracks on in-service components.
A highly-sensitive oil-based magnetic particle aerosol for nonfluorescent (visible) wet method magnetic particle testing to locate fine and medium discontinuities on finished parts.
ML-72B provides clear, strong indications due to the heavy buildup of the highly magnetic particles. The convenient aerosol packaging is ideal for field testing, spot inspections and places where bulk processing is impractical, and the wide spray pattern makes it easy to cover large areas for faster processing during remote inspections of tubing, piping and large structures.
A bright white, opaque NDT contrast paint, provides a high
contrast background to improve probability of detection and sensitivity during
visible magnetic particle inspections.
This fast drying paint aerosol sprays on evenly, without
flaking, before inspection so when non-florescent / colored magnetic particles
are applied, the indications appear clearly against the opaque white