ASME SA-320 / SA-320M Bolting Specification
ASME Boiler and Pressure Vessel Code, Section II Part A
ASME SA-320 / SA-320M is the bolting specification adopted by the ASME Boiler and Pressure Vessel Code Section II Part A for low-temperature service. SA-320 is the direct ASME equivalent of ASTM A320, adopted without technical deviation. Saudi Aramco, ADNOC, NORSOK, and other Middle East and North Sea pressure-equipment programs typically cite the ASME SA-320 designation in their project specifications even when ASTM A320 material is delivered.
SA-320 grades covered
SA-320 mirrors all ASTM A320 grades. The ferritic / martensitic alloy steel L-series (L7, L7M, L7A, L7B, L7C, L43, L70, L71, L72, L73) and the austenitic stainless B-series (B8, B8M, B8C, B8F, B8P, B8T, B8LN, B8MLN). Each ASTM A320 grade ships against the corresponding ASME SA-320 designation on the EN 10204 3.1 / 3.2 certificate without any chemical or mechanical adjustment.
ASTM vs ASME documentation
- ASTM A320 / A320M is published by ASTM International (Committee F16 on Fasteners)
- ASME SA-320 / SA-320M is adopted by ASME under BPVC Section II Part A without technical deviation
- ASME adoption confers automatic acceptance under BPVC Section VIII Division 1 / Division 2 pressure-vessel construction
When to cite ASME SA-320 versus ASTM A320
For ASME BPVC-stamped vessels and Aramco / ADNOC / Saipem / Petrobras project specifications, cite ASME SA-320. For commercial procurement and ASTM-aligned QA frameworks, cite ASTM A320. Test reports may dual-stamp ("ASTM A320 / ASME SA-320 Grade L7") to satisfy both QA paths.