Liquid Permeability Checks whether the casting is qualified
Liquid penetration testing is used to check for defects such as surface cracks, surface pinholes, and the like that are difficult to detect on the surface of a casting. Commonly used penetration testing is coloring detection, it is a high permeability of the colored (usually red) liquid (penetrant) soaked or sprayed on the casting surface, penetration agent into the opening defects inside, quickly wipe the surface permeate Layer, and then easy to dry display agent (also called the imaging agent) sprayed on the casting surface, to be left in the defect in the impermeable agent sucked out, the display agent was dyed, which can reflect the shape of the defect, Size and distribution. It is pointed out that the accuracy of the penetration test decreases with the increase of the surface roughness of the tested material, that is, the better the surface detection effect is, the surface detection accuracy of the grinder is the highest, and even the intergranular crack can be detected. In addition to color detection, the fluorescence penetration test is also commonly used liquid penetration detection method, it needs to configure the UV light irradiation observation, detection sensitivity than coloring detection.