Liquid Penetrant Test (LPT)
Liquid Penetrant Test (LPT)
Liquid Penetrant Testing (LPT) finds surface-breaking flaws like cracks, porosity, and lack of fusion in non-porous materials (metals, ceramics, plastics) by using capillary action to draw dye into defects, revealing them after applying a developer, widely used in aerospace, automotive, oil & gas for inspecting welds, castings, and critical components to ensure structural integrity.
Uses
- Surface Cracks:Hairline cracks from fatigue, manufacturing, or stress.
- Porosity:Tiny holes or voids on the surface.
- Lack of Fusion/Inclusions:Gaps or foreign material in welds/castings.
- Seams & Cold Shuts:Surface separations in forged or machined parts.
- Corrosion Pits:Pits from inter-granular corrosion.
Applications
Aerospace:Aircraft components, turbine engines, landing gear, structural welds.
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- Automotive:Engine parts, castings, welds on chassis.
- Oil & Gas:Pipelines, pressure vessels, valves, storage tanks.
- Power Generation:Turbines, boilers, processing equipment.
- General Manufacturing:Welds, castings, forgings, machined parts, non-ferrous metals (like aluminum, titanium).
- Cryogenics:Inspecting equipment for defects under extreme cold.



