– Surface creases where two streams of molten metal meet but fail to fuse completely.
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:
To purchase the official ANSI/MSS SP-55-2025 PDF, visit the MSS website at or contact an authorized standards distributor. mss sp-55 standard pdf
Understanding MSS SP-55 Standard: Quality Control for Steel Castings
Using pirated or low-resolution scanned copies of the PDF can lead to compliance failures, as poor image resolution renders the reference photographs useless for precise visual comparison. – Surface creases where two streams of molten
Mastering Visual Inspection: A Guide to the MSS SP-55 Standard
For most defect types, the standard provides a series of five photographic examples, typically labeled from A to E. Understanding MSS SP-55 Standard: Quality Control for Steel
MSS SP-55 uses a "Reference Photo" system to determine what is acceptable:
Minor irregularities that do not compromise pressure-containing integrity.