Mss Sp-55 Standard Pdf -

: The standard is intended for use on any 4 in. x 5 in. (100mm x 125mm) area of a casting surface.

The standard classifies defects into to ensure inspectors use consistent terminology:

– Slightly raised sand-crusted metal blemishes. mss sp-55 standard pdf

– Linear fractures; generally never acceptable.

: Twelve types of irregularities are categorized, with five examples for each—two showing acceptable levels and three showing rejectable ones. Categories of Surface Irregularities : The standard is intended for use on any 4 in

– Sand trapped in the molten metal showing on the surface.

– Voids caused by metal contracting during solidification. The standard classifies defects into to ensure inspectors

– Shallow depressions from mold surface faulting.

– Surface folds from incomplete metal fusing.

The edition recently replaced the 2011 version. A major update in this version is the inclusion of iron and ductile iron castings , expanding the standard's scope beyond just steel. It also aims to align surface quality expectations more closely between manufacturers and purchasers in the broader piping industry. MSS SP-55 - Manufacturers Standardization Society