FP 91 high-sensitivity fluorescent penetrant
In industrial processes where inspection reliability is essential, the choice of penetrant makes all the difference. Metal-Chek FP 91 was developed for water-washable fluorescent penetrant testing, offering clear indications, intense fluorescence, and easy removal – characteristics that directly contribute to more productive and safer inspections.
Classified as Type I, Method A, Level 2 , FP 91 is a medium-sensitivity , water-washable fluorescent penetrant , indicated for the detection of surface discontinuities in non-porous materials that require greater sensitivity in the test. Its inspection should be carried out with 365 nm UV-A light , according to the product’s technical instructions.
High sensitivity for more visible indications.
One of the main advantages of FP 91 is its ability to generate sharper indications with an intense fluorescent yellow-green color . In practice, this facilitates the visualization of discontinuities during inspection, especially in controlled environments with adequate lighting, even when using the developer-free technique.
This high detection capability is crucial in applications where small surface flaws can compromise the quality, safety, or performance of the inspected component.
Low background fluorescence: more contrast during inspection.
In addition to the intensity of the indications, the FP 91 exhibits low background fluorescence . This difference contributes to better contrast between the inspected area and any indications, reducing visual interference and facilitating a clearer reading by the inspector.
In fluorescent assays, this point is especially important, as a surface with excessive background can hinder the correct identification of discontinuities.
Washable with water and easy to remove.
FP 91 belongs to Method A , meaning it is a water-washable penetrant . This makes the process of removing excess more practical, as it can be done with a water spray or with clean, dry cloths that are then slightly moistened, according to the technical procedure.
The ease of removal helps optimize the inspection process, maintaining efficiency without compromising test quality. The description also provides guidance on how to avoid excessive washing, preserving the indication of potential defects.
Versatile application in different materials and processes.
The Metal-Chek FP 91 can be used in a wide variety of industrial applications, including materials testing:
- forged;
- laminates;
- fused;
- welds;
- manufacturing steps;
- Maintenance of assembled sets or components.
It can also be applied to ferrous and non-ferrous metals , non-porous ceramics, glass and various types of plastics, provided that the surface is within the temperature range indicated for the test, between 10 °C and 52 °C .
Low material consumption
FP 91 also stands out for its low material consumption , related to less drag during the process and excellent wetting. This factor can contribute to greater product utilization, especially in industrial routines with a high frequency of inspections.
Aerosol version FP 91 HI: practical application.
In addition to larger volume packaging, FP 91 is also available in an aerosol version with hydrocarbon propellant, FP 91 HI . This option is suitable for spray applications, offering practicality for spot inspections, maintenance, and situations where the use of portable packaging facilitates fieldwork.
The aerosol version retains the product’s main characteristics: intense fluorescence, easy removal with water, low background fluorescence, and clear indication of surface discontinuities.
Compliance with recognized standards and specifications.
Another important distinguishing feature of the FP 91 is its compliance with specifications widely used in the industrial market. The product meets requirements such as:
AMS 2644, ISO 3452-2, ASTM E-1417, ASTM E-165, ASME Section V Article 6, PETROBRAS N-2370 and N-1596.
This set of specifications reinforces the suitability of the FP 91 for applications in industrial environments that require technical control, standardization, and traceability of inspection processes.
How does FP 91 contribute to more efficient inspections?
By combining high fluorescent intensity, low background fluorescence, ease of removal, and good durability of indications, FP 91 contributes to a more efficient and reliable assay.
Among the main advantages of the product, the following stand out:
Greater clarity of indications , facilitating the identification of surface discontinuities;
Better visual contrast , due to low background fluorescence;
It is easy to operate because it is washable with water;
Versatile application , in different materials and industrial stages;
Low consumption , contributing to better product utilization;
Aerosol option , ideal for practical and localized applications;
Compliance with technical standards is important for qualified industrial processes.
Metal-Chek FP 91 is an efficient solution for fluorescent penetrant testing on non-porous materials requiring higher sensitivity. Its high revelation capacity, combined with ease of removal and low background fluorescence, makes it an excellent choice for industrial inspections demanding clarity, productivity, and reliability.
For best results, use should follow the applicable inspection procedure, with a properly cleaned surface, adequate penetration time, controlled removal of excess, uniform application of the developer, and inspection under appropriate light intensity.
Excellence in products for those seeking reliable results.
Metal-Chek provides complete solutions for Non-Destructive Testing: penetrant liquids, removers, developers, lighting fixtures and accessories, developed according to the main ASTM, ISO, ASME, NM and PETROBRAS standards , guaranteeing quality, safety and technical compliance in every inspection.
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