– Ridges on the surface from mold sand cracking.
The inspector compares the actual casting surface to the reference photographs in the official MSS SP-55 PDF.
"Quality Standard for Steel Castings for Valves, Flanges, Fittings, and Other Piping Components – Visual Method for Evaluation of Surface Irregularities,"
For most defect types, the standard provides a series of five photographic examples, typically labeled from A to E. mss sp-55 standard pdf
Clearly define acceptance and rejection criteria between buyer and seller. Prevent premature failures in critical applications. Types of Surface Irregularities Covered
Manufacturers Standardization Society (MSS)
MSS SP-55 classifies surface conditions, including Hot Tears and Cracks, Shrinkage, Sand Inclusions, Gas Porosity, Veining, Rat Tails, Wrinkles & Cold Shuts, Cutting Marks, Scabs, Chaplets, Weld Repair Areas, and Surface Roughness, per this Scribd document and Valve World Americas. Versions and PDF Availability What is the MSS SP standard and what is it for? - Redfluid – Ridges on the surface from mold sand cracking
MSS SP-55 solved this problem by creating a standardized visual method supported by reference photographs. These images allow inspectors to compare an actual casting surface directly against accepted benchmarks, establishing a clear, repeatable pass-fail criterion.
If you are involved in procurement, quality control, or inspection of steel castings, ensuring your team has access to the latest is a crucial step in maintaining piping integrity.
is the premier global quality standard for evaluating surface irregularities on steel castings used in valves, flanges, and fittings . Developed by the Manufacturers Standardization Society (MSS) of the Valve and Fittings Industry, this standard provides visual and tactile criteria to determine whether a casting is acceptable or requires rejection or repair. Versions and PDF Availability What is the MSS
The official MSS SP-55 standard is a copyrighted document protected by intellectual property laws. Unauthorized reproduction or distribution is prohibited under copyright convention unless written permission is granted by the Manufacturers Standardization Society.
For those searching for the , it is crucial to understand its core purpose and application. What is MSS SP-55?
: If certain defect types are not applicable or are exempted for a particular product, clearly note these exemptions in quotations and product specifications.
– Grooves or rough surfaces left behind by the removal of risers, gates, or previous defects.
A Table in Section 7 of the standard provides MSS's interpretation of the relationship between the standard's acceptance criteria and the surface quality levels illustrated by the CTI comparators and associated photographs.