The Non Destructive Testing with Penetrant Liquids is an inspection procedure of the surface integrity of a ferrous or non ferrous piece and, possibly, superficially non-porous during the testing. The penetrant is applied by spraying, brush or immersion allowing capillary action to act for the necessary time for the in emerging defects.
Then the excess penetrant is removed.
At the end of this procedure, wich occurs by washing, removal with wet rags or immersion in emulsifiable liquid, the surface should be free of traces of penetrating. Finally, the detector is applied (in the same way it has been applied the penetrant), it will allow the penetrated liquid to resurface superficially.
It will be possible, in this way, thanks to the action of capillarità, detect to the examined piece any defects surfaced. Typically the penetrant is red, while the detector is white; this chromatic difference lets be readily seen any defect outcropping. Rovergamma carries out penetrant fluorescent testings too.