Acceptance standards for surface quality of precision castings

Acceptance standards for surface quality of precision castings

The surface quality of precision castings mainly includes surface defects, dimensional accuracy, shape deviation, surface roughness, surface cleaning quality, etc. Today, precision casting manufacturer Tianyao Metal will discuss the acceptance standards for surface quality of precision castings.

1. The sprue and riser on the non machined surface of precision castings must be cleaned to the same level as the casting surface, and the residual amount of sprue and riser on the machined surface should meet the technical requirements;

2. Cracks, through-holes, penetrating cold shuts, penetrating shrinkage, slag inclusions, and other defects that cannot be removed by mechanical processing are not allowed on precision castings;

3. Burrs, seams, molding sand, and sand cores on the non machined surface of precision castings should be cleaned thoroughly;

4. Precision castings generally have any defects on the surface to be machined that do not exceed the machining allowance range; Important machining surfaces are allowed to have defects that do not exceed 2/3 of the machining allowance, but crack defects should be removed; The processed surface allows for casting defects with non contiguous holes with a diameter * length * depth of 2 * 2 * 2 or less;

5. As the machining reference surface (hole) and measurement reference, the surface of precision castings should have a flatness of less than or equal to 2.0 millimeters and a roughness of Ra50 or less;

6. Surface porosity, sand holes, and slag inclusion areas of precision castings are not large, but surfaces that are relatively dispersed or have continuous pitting will not be accepted;

Precision machining