In addition, this may also produce false indications severely hindering the ability to do a proper inspection. Ultraviolet UV-A radiation of adequate intensity 1, micro-watts per centimeter squared is commonalong with low ambient light levels less than 2 foot-candles for fluorescent penetrant examinations. The use of written procedures has evolved, giving the ability for design engineers and manufacturers to get the high standard results from any properly trained and certified liquid liquid penetration examination testing technician. Water-washable, solvent-removable, lipophilic post-emulsifiable, or hydrophilic post-emulsifiable are the common choices.
The indications produced are much broader than the actual flaw and are therefore more easily visible. The method can be manual, semi-automatic or fully automated.
Aerospace Event About the event Information for Exhibitors CM About the conference Abstract and full paper submission Registration Key dates and participation Keynote speakers and structured session organisers Exhibitors booking form Venue and accommodation Sponsorship packages Travel information Travel and attendance award Best student paper award About the organisers List of sponsors. Any areas that bleed out can indicate the location, orientation and possible types of defects on the surface.
In each of these three groups the penetrant solution can contain a dye to make the indication visible under white light, or a fluorescent material which fluoresces under suitable ultraviolet UV-A light. Some cleaning methods have been shown to be detrimental to test sensitivity, so acid etching to remove metal smearing and re-open the defect may be necessary.