The Ultimate Guide to Fluorescent Penetrant Inspection for Aircrafts
Fluorescent penetrant inspection, also referred to as “dye penetrant inspection” or “liquid penetrant inspection”, is a thorough, non-destructive testing method used on safety-critical components in the aircraft inspection and maintenance to detect surface cracks, seams or discontinuities in parts. If left undetected, surface cracks can propagate, which can ultimately cause part failure – and even catastrophic damage. That is why this inspection is so important.
How It Works
Fluorescent penetrant inspection uses a dye penetrant that fluoresces under UV-A black light. This fluorescent dye becomes stuck in any surface indications and then becomes observable under black light during the inspection process. When a developer is then applied, these cracks are visible to the naked eye.
Benefits of Fluorescent Penetrant Inspection
As a safety-critical part of your aircraft ages, it’s important to perform routine evaluations to spot issues early and ensure safe operations. Fluorescent penetrant inspection accurately detects miniscule damage quickly and efficiently. This is just one of the many benefits of using FPI, including:
There are several options of materials and applications. This inspection can be performed on most materials that are not extremely rough or porous, including material composition that is metallic or nonmetallic, magnetic or nonmagnetic and conductive or nonconductive.
It allows teams to rapidly and harmlessly inspect large areas on safety-critical components. Parts or materials of virtually any size, shape or volume can be inspected. The test is also efficient, easy to perform and produces quick results.
The inspection has the ability to identify small surface discontinuities that may be missed using other tests. Fluorescent liquid penetrants are ‘higher sensitivity” penetrants, which means they have the capability to detect smaller cracks and defects.
Fluorescent Penetrants Options / Methods
We offer several series of penetrants, all of which are QPL-certified. A few of our most requested penetrant systems are outlined below:
Fluorescent Penetrants – Biodegradable
- Biodegradable Penetrants by Met-L-Chek® are water-washable and solvent-removable and are used for the detection of fine cracks, porosity, and through-leaks on metals, composites, synthetic materials and even plastics. The materials used are low in sulfur, halogens, VOC-free and safe for use on all metal surfaces.
- Met-L-Chek® FBP Series Penetrants are bright yellow, smooth washing and non-gel forming, allowing them to wash cleanly from rough surfaces.
- For Method C applications, use with an approved Met-L-Chek® solvent cleaner. The Met-L-Chek® family of solvent cleaners includes E-59, E-59A, R-503, and R-504.
Fluorescent Penetrants – Water Washable
- All Met-L-Chek® Method A[i] & C[ii] Fluorescent Water Washable Penetrants are SAE AMS 2644 QPL certified, meeting the requirements of AMS 2647, ASTM E1417, ASTM E165, ASTM E1209, ISO/FDIS 3452.
- Met-L-Chek® Method A & C Fluorescent Water Washable Penetrants are also solvent-removable and used for the detection of fine cracks, porosity, and through-leaks on metals, composites, synthetic materials and plastics. The materials used are low in sulfur, halogens and safe for use on all metal surfaces.
- Met-L-Chek® Method A & C Fluorescent Water Washable Penetrants are bright yellow, smooth washing and non-gel forming, allowing them to wash cleanly from rough surfaces.
- For Method C applications, use with an approved Met-L-Chek® solvent cleaner. The Met-L-Chek® family of solvent cleaners includes E-59, E-59A, R-503, and R-504.
Fluorescent Penetrants – Post Emulsifiable
- All Met-L-Chek® Post Emulsifiable Penetrants are SAE AMS 2644 QPL-certified, meeting the requirements of AMS 2647, ASTM E1417, ASTM E165, ASTM E1209, ISO/FDIS 3452.
- Met-L-Chek® Post Emulsifiable Penetrants are used in Methods B[iii], C & D[iv] for the detection of fine cracks, porosity, and through-leaks on metals, composites, synthetic materials and some plastics. They are low in sulfur and halogens and safe for use on all metal surfaces.
- For Method B applications, use with Met-L-Chek® E-57 emulsifier.
- For Method C applications, use with an approved Met-L-Chek® solvent cleaner. The Met-L-Chek® family of solvent cleaners include E-59, E-59A, R-503, and R-504.
- For Method D applications, use with Met-L-Chek® E-58D emulsifier.
Check out the links below to learn more about the four different “methods” of fluorescent penetrants, and send us a message to set up a consultation today.
METHOD A: FLUORESCENT PENETRANT WATER WASHABLE INSTRUCTIONS
METHOD B: FLUORESCENT PENETRANT POST-EMULSIFIABLE, LIPOPHILIC INSTRUCTIONS
METHOD C: FLUORESCENT PENETRANT SOLVENT-REMOVABLE (WIPE-OFF) INSTRUCTIONS
METHOD D: FLUORESCENT PENETRANT POST-EMULSIFIABLE, HYDROPHILIC INSTRUCTIONS