The standard, titled "Quality Standard for Steel Castings for Valves, Flanges, Fittings, and Other Piping Components—Visual Method for Evaluation of Surface Irregularities," is a critical industry guideline published by the Manufacturers Standardization Society (MSS)0;91;. It provides a standardized visual methodology for assessing the surface quality of steel castings used in piping systems. 0;92;0;a1; 0;baf;0;d1; 1. Scope and Purpose
For industries that rely on fluid control—such as oil & gas, petrochemical, power generation, and water treatment—the integrity of cast components is non-negotiable. One critical document that helps ensure this integrity is . mss sp-55 standard pdf
MSS SP-55
"If it passes SP-55, no NDT is needed." Fact: SP-55 is a visual standard. You still need MPI (magnetic particle) or PT (penetrant testing) for critical high-pressure applications. The standard, titled "Quality Standard for Steel Castings