non destructive services
holiday detection
Holiday Detection (HD) is used for the detection of defects, pinholes & porosity in the coatings on conductive items. These could be pipelines or tanks which have protective coatings. This test is used as a safeguard against corrosion.
The equipment for this test is extremely portable, and electrically indicates a flaw when the current in completed. The machine has to be earthed to the conductive material.
The ideal time to carry out Holiday Detection is immediately after new coatings are applied. This will identify repair areas before any corrosion can have taken place. Holiday detection is suitable for all types of coatings like Fusion bonded epoxy, coal tar epoxy, paints, polyester, polyurethane, pipeline tapes, Heat shrinks and Asphalt.
A test voltage is applied to the coating by moving a brush probe across the surface and where there is either a pinhole or flaw the voltage will spark through the coating at the flawed location a red flashing indicator will flash and an audible alarm will sound the detected flaw can now be marked for subsequent repair and testing resumed for the remaining surface area, if no flaws are detected the test will therefore be non-destructive.
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WIS have implemented and are now accredited to the following: EN ISO 9001:2015, EN ISO 14001:2015 and EN ISO 45001:2018.
WIS have attended courses and examinations at QSA-Global in Houston, Texas and now have technicians trained and qualified in Servicing & Maintenance of the QSA-Global equipment. WIS also have technicians trained and qualified in Source Retrieval, this entailed the actual retrieval of a live source, which other companies providing this service do not carry out. WIS intend to roll out these services to NDT Contractors nationwide.