EN
TRPenetrant inspection is a method used to detect surface defects. The defects must be open to the inspection surface, so defects that are below the surface or have closed openings cannot be detected using this method.
Scientific Basis
A penetrant liquid that has penetrated into discontinuities on the inspection surface through capillary action is drawn back to the surface by a developer, resulting in indications of discontinuities. If the discontinuity is a crack, linear indications are obtained, and if it is a pore, round indications are obtained.
Applications
It can be used to detect expected surface defects in all metallic or non-metallic materials.
Limitations
If the inspection part has a highly porous structure, it is difficult to apply this method effectively. Only defects that are open to the surface can be detected. Improper surface cleaning can have a direct negative impact. Additional cleaning may be required after inspection. The use of chemical substances requires special care (e.g. waste).
Procedure
- Pre-cleaning of the inspection surface
- Application of penetrant
- Waiting for penetration
- Intermediate cleaning
- Development
- Inspection
- Evaluation and report preparation
- Final cleaning
EN and ISO Standards Used
General:
EN ISO 3452-1 - Non-destructive testing - Penetrant testing - Part 1: General principles
EN ISO 3452-2 - Non-destructive testing - Penetrant testing - Part 2: Testing of penetrant materials
EN ISO 3452-3 - Non-destructive testing - Penetrant testing - Part 3: Reference test blocks
EN ISO 3452-4 - Non-destructive testing - Penetrant testing - Part 4: Equipment
EN ISO 3059 - Non-destructive testing - Penetrant testing and magnetic particle testing - Viewing conditions
Sources:
EN ISO 23277 - Non-destructive testing of welds - Penetrant testing of welds - Acceptance levels
Castings:
EN 1371-1 - Castings - Liquid penetrant inspection - Part 1: Sand, gravity die and low pressure die castings
EN 1371-2 - Castings - Liquid penetrant inspection - Part 2: Investment castings
Steel forgings:
EN 10228-2 - Non-destructive testing of steel forgings - Part 2: Penetrant testing
Steel pipes:
EN ISO 10893-4 - Non-destructive testing of steel pipes - Part 4: Liquid penetrant inspection of seamless and welded steel pipes for the detection of surface imperfections
