
Dye Penetrant Inspection is a proven and highly versatile NDT technique used to detect surface-breaking defects in both ferrous and non-ferrous materials. At Inspection Quality, we offer DPI services using both visible (colour contrast) and fluorescent dyes, depending on your inspection requirements and environment. This method is widely used in industries such as aerospace, automotive, petrochemical, and fabrication.
The process involves applying a penetrant liquid to the surface of the part, allowing it to seep into surface flaws. After a suitable dwell time, the excess dye is removed, and a developer is applied to draw out the trapped penetrant. Any flaws become clearly visible under appropriate lighting conditions. DPI is especially effective for detecting cracks, porosity, laps, and fatigue damage in non-magnetic materials.
Common uses of DPI include:
- Enhances quality assurance and reduces product failure risk
- Weld inspection in stainless steels and aluminum alloys
- Surface checks on castings, valves, and turbine blades
- In-service inspection of high-performance aerospace parts
- Routine checks in manufacturing and fabrication workshops
DPI Advantages:
- Simple, portable, and cost-effective
- Highly sensitive to small, tight surface cracks
- Suitable for complex geometries and irregular shapes
- Compliant with standards such as ISO 3452 and ASTM E1417
