Description
Transparent Crack Comparators are fluorescent comparators that consist of a number of transparent tokens, typically measuring 30 × 100 mm and a few mm thick, having green fluorescent marks of known dimensions.
The various designs offer dots and lines of known dimensions, while some provide fluorescent circles to estimate the indications’ spacing and grouping accurately. The markings on the comparators appear a brilliant green when viewed under UV-A of a peak wavelength of 365nm. Under white light illumination, they appear bright green. There are 13 various designs which cover a wide range of applications in magnetic particle inspection, penetrant testing, radiography and visual inspection.
These markings are green in daylight and fluorescent under UV-A 365mm. The comparators are transparent, they can be used in the zones to be examined by putting them above the indications and by performing a direct verification of “congruence” with the known dimension on the comparator. Furthermore, three of these comparators (Types 6, 7 and 8) are designed to help the inspector evaluate the distance of the indications.
