AS ISO 3452.1:2020 Non-destructive testing – Penetrant testing Part 1: General principles

AS ISO 3452.1:2020 Non-destructive testing – Penetrant testing Part 1: General principles. 8.4.2 Penetration time The appropriate penetration time depends on the properties of the penetrant, the application temperature, the material of the part to be tested and the discontinuities to be detected. The penetration time shall be between 5 mm and 60 mm and shall not be less than the manufacturer’s recommended time for the required sensitivity. The penetration time shall be recorded in the written test procedure. 8.5 Excess penetrant removal 8.5.1 General The application of the remover medium shall be such that penetrant remains in the discontinuities. 8.5.2 Water The excess penetrant shall be removed by washing (rinsing), immersion or wiping using water. Care shall be taken to minimize the effect of mechanical action caused by the rinsing method. 8.5.3 Solvents Excess penetrant shall be removed, first, by using a clean lint-free cloth and, subsequently, by cleaning with a clean lint-free cloth lightly moistened with solvent. Any other removal technique shall be technically approved for adequacy and agreed by the contracting parties, particularly when solvent remover is sprayed directly onto the part to be tested. 8.5.4 Emulsifier 8.5.4.1 Hydrophilic (water-dilutable) To allow the post-emulsifiable penetrant to be removed from the test surface, it shall be rendered waterrinsable by application of an emulsifier. Before the application of the emulsifier, a water wash should be performed in order to remove the bulk of the excess penetrant from the test surface and facilitate a uniform action of the hydrophilic emulsifier that will be applied subsequently. The emulsifier shall be applied by immersion or by foam equipment. The concentration and the contact time of the emulsifier shall be evaluated by the user through pre-tests according to the manufacturer’s instructions. The predetermined emulsifier contact time shall not be exceeded. After emulsification, a final wash shall be carried out in accordance with 8.5.2. 8.5.4.2 Lipophilic (oil-based) To allow the post-emulsifiable penetrant to be removed from the test surface, it shall be rendered waterrinsable by application of an emulsifier. This can only be done by immersion. The emulsifier contact time shall be evaluated by the user through pre-tests according to the manufacturer’s instructions. This time shall be sufficient to allow only the excess penetrant to be removed from the test surface during the subsequent water wash. The emulsifying time shall not be exceeded. Immediately after emulsification, a water wash shall be carried out in...