Met-L-Chek VP-31A Visible Dye Penetrant
VP-31A is a visible (Type 2), post emulsifiable (Method B) and solvent removable (Method C) inspection penetrant. It is designed for use in general metalworking, welding, nuclear and automotive applications for surface flaw and through leak detection.
VP-31A is used with E-50 emulsifier for Method B processing which renders the penetrant water washable.
VP-31A used with D-70 non aqueous developer forms a uniform background to facilitate discontinuity detection.
VP-31A is qualified to AMS-2644 . They meet the requirements of ASME Boiler and Pressure Vessel Code, ASTM E-165, and ASTM E-1417 for penetrant inspection. They are low in Sulfur, Chlorine, and other Halogens, making them safe for use on Titanium and high Nickel alloys in nuclear applications. They are certified to NAVSEA 250-1500-1, RDT, EDF and RCC-M. Visible inspection penetrants are used primarily for field applications where darkening the inspection area and the use of a black light (UVA) is impractical, in maintenance repair and safety checks, and in manufacturing processes where a visible indication helps in locating the area for subsequent repair work, such as in large rough castings. Visible penetrants are also used for through leak testing of heat exchangers and tanks, where penetrant is applied to one side and developer to the other. Visible penetrants are not rated by sensitivity levels per AMS-2644 but are considered approximate to level 1 fluorescent penetrants. 50μ discontinuities are readily detected and under controlled conditions 30μ size defects may be highlighted by visible penetrants.
Cross Reference Penetrant Chart - click on the links for more information