The method employs a penetrating liquid, which is applied over the surface of the component under examination and enters the discontinuity or crack. Subsequently, after the excess penetrant has been removed from the surface, the penetrant that exudes or is drawn back out of the crack or discontinuity is observed.
Liquid penetrant testing can be applied to any non-porous clean material, metallic or non-metallic, but is unsuitable for dirty or very rough surfaces. Penetrants can contain a dye to make the indication visible under white light, or a fluorescent material that fluoresces under suitable ultra-violet light.
Dye penetrant inspection is the one Non Destructive Testing method used extensively to evaluate the condition or quality of a component. It is easily carried out, inexpensive and usually does not require any special equipment and is used to reveal surface breaking flaws by bleedout of a coloured or fluorescent dye from the flaw.
This method of testing can be applied to ferromagnetic and non-ferromagnetic materials, however it is most commonly used in non-ferromagnetic components for example when magnetic particle examination (MT) is not practical.
Independent Integrity Inspection Limited (INDEI) utilises highly professional personnel qualified to PCN and SNT qualifications to enable on-site and laboratory based penetrant testing services with fluorescent, visible, water-washable and solvent based techniques to be meet your requirements and the requirements of your clients.