How to make Liquid Penetrant Inspection

The examinations were used to detect surface defects on porous solids are not porous. Defects that occur may arise because the manufacturing process or because of fatigue (fatigue) on the object that has been in use long enough. Cracks in investigating the cracks on the surface, and can not detect defects in the surface or near surface. This method is very effective and efficient use in the examination without damage, while relatively less expensive. The detection of cracks in this way does not depend on the size, shape, material structure, composition, and direction of cracks. Because the liquid penetrant can seep into the test object. This absorption occurs because there is a capillary power (low surface tension). His usage is not limited to ferrous metals and non ferrous metals, but can also be used in ceramics, plastic, glass and other objects of powder metallurgical process.

The liquid penetrant process following the steps below:
-Prepare the surface, in the sense of specimen surface must be clean and dry.
-Penetration, sprays penetrant on the surface of the specimen and allowed to stand for about 10 minutes for penetrant to enter into the cracks.
-Cleaning, this is done with the wash penetrant from the surface of the specimen carefully, and tries to clean the same direction.
-Developer, the developer material is sprayed onto the specimen surface so as penetrant enters the cracks will be lifted to the surface.
-Inspection, the observation specimen after the spray penetrant and will appear on specimen defects or cracks. Checks can be carried out under sufficient light or using ultraviolet light.

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