scope:

This European Standard specifies methods for the examination of surface condition (roughness and surface discontinuities) of castings. This European Standard is applicable to all cast metals and all casting processes except die casting. The surface roughness of a casting is influenced by the manufacturing process (moulding, grinding, finishing, etc.), the moulding materials used (sand, coating, etc.), the production equipment available and the alloy cast. Depending on the applications of the casting, the surface requirements are related to mechanical loadings, appearance, surface treatment, etc. Since cast surfaces do not exhibit the same cyclic character as machined surfaces it is difficult to evaluate their roughness using conventional mechanical, optical, or pneumatic devices. Other optical/electronic means are now available for measuring surface roughness of cast surfaces. For the ease of use, visual tactile comparators are preferred. Moreover, in order to take into account the irregularities on as-cast surfaces, ground surfaces or other means of finishing of castings, comparators should have relatively large dimensions in order to make them more reliable and their results repeatable and consistent.