What does "DPI" stand for in the context of Penetrant Testing?

DPI stands for Dye Penetrant Inspection in the context of Penetrant Testing. This technique is widely used in non-destructive testing to identify surface defects in non-porous materials. The process involves applying a penetrant dye to the surface of the test material, which seeps into any surface-breaking flaws. After a specified dwell time, the excess dye is removed, and a developer is applied. The developer draws out the penetrant trapped in the defects, creating a visible indication that can be easily inspected under UV light or white light.

Dye Penetrant Inspection is valued for its sensitivity to small cracks or flaws, ease of use, and low cost compared to other non-destructive testing methods. It is applicable to various materials, including metals and plastics, which makes it a versatile choice in quality control and maintenance inspections in various industries.