: If the irregularity is less severe than the "Acceptable" reference photo for that specific type, the casting passes.
| Standard | Scope | Difference from MSS SP-55 | | :--- | :--- | :--- | | | Valves, fittings, flanges (piping components) | Focus on functionality under pressure. | | ASTM A802 | General steel castings (any use) | Less stringent on pressure-containing parts. | | ISO 4990 | General casting inspection | Lacks specific visual comparators. | mss sp-55 standard pdf
You're looking for information on the MSS SP-55 standard in PDF format. : If the irregularity is less severe than