Machine tool castings nondestructive inspection method
Publish Time: 2016-11-25 Origin: Site
After casting produced, quality detection is an essential link.This paper mainly do the simple introduction and analysis of machine tool castings nondestructive testing.
Tests for the machine tool castings, usually by the two parties agree beforehand good reference to the technical requirements on the drawings provided by purchasing or technology contract.These requirements are general in national, ministerial standard or industry standard as the basis, of course, also have the two sides in the contract order to determine the technical requirements.
Machine tool castings quality testing, generally include inspection of size, shape and appearance of the surface quality of the visual inspection, and chemical composition analysis and mechanical property test, here is the nondestructive testing methods.The specific method is as follows:
1, magnetic powder inspection: all machine tool castings surface and internal to accept magnetic powder inspection.
2, liquid penetrant inspection check: all machine tool castings surface and internal check accept liquid penetrant inspection.
3, machine tool castings to be 100% full X-ray film.
4, if the rules and regulations of product requirements of nondestructive testing shall be carried out according to the corresponding norms.The structure of machine tool castings to ensure the quality, simplify the process.The structure of machine tool castings can't easily change, if you need to modify should explain to product designers.
The structure of machine tool castings with rounded corners.Avoid acute Angle connection, the connection between the thick wall and thin wall to gradually transition.Slow muscle, radial shrinkage resistance;Easy to draw and reduce the amount of parting surface, avoid big flat structure, parting surface should be as far as possible for the flat face;Convex, the design of the rod should be easy to draw.Should try to reduce the number of cores, avoid unnecessary cores, facilitate core fixed, exhaust and clean up.
Machine tool castings of continued after solidification cooling process, the solid-state contraction impeded, machine tool castings to produce internal stress. Machine tool casting alloy by casting line contraction, core, pouring at mechanical obstacles and formation of the internal stress of the system. Internal stress is stress for the time being. The thermal stress is due to the machine tool castings uneven wall thickness, different cooling rate, the parts that the machine tool castings in the same period shrinkage internal stress which is caused by the inconsistency of the parts.