Mss Sp-55 Standard Pdf -

: Pits or trapped material on the surface. Shrinkage (Rechupe) : Voids caused by metal cooling.

The MSS SP-55 standard covers a wide range of steel valves, flanges, fittings, and other piping components, including:

As casting technologies continue to evolve—particularly with the growing adoption of lost foam casting, 3D-printed sand molds, and additive manufacturing—surface defect characteristics and evaluation methods will need to keep pace. Future revisions of MSS SP-55 may consider:

: It uses a set of 60 reference photographs to establish a baseline for surface quality.