This page presents the ASTM A193 Gr B8UN material specification as manufactured to at Ananka Fasteners Pvt Ltd. A193 Grade B8UN covers 254 SMO (UNS S31254) super-austenitic stainless bolting for aggressive chloride and seawater service. The chemistry and mechanical properties below are the values delivered to on every fastener released against this specification.
A193 Grade B8UN covers 254 SMO (UNS S31254) super-austenitic stainless bolting for aggressive chloride and seawater service.
| Specification | ASTM A193 Gr B8UN | Governs | Chemistry and mechanicals for one or more grades of fastener material |
| Grades Covered | SS 254 SMO | Product Forms | Bolts / Screws / Studs / Nuts / Washers as manufactured to the geometry standard |
| Related Dimensional Standards | ASME B18.2.1, DIN 931/933, ISO 4014, BS 3692 | Datasheets Referencing this Spec | 16 |
| Certification | EN 10204 3.1 / 3.2 | Testing | PMI, chemistry, tensile, hardness, IGC where applicable |
The following material grades are supplied by Ananka to ASTM A193 Gr B8UN:
Composition limits shown are representative for the primary grade governed by this specification. Consult the individual grade datasheet for exact limits.
| Element | Composition, % |
|---|---|
| Chromium | 19.5–20.5 |
| Nickel | 17.5–18.5 |
| Molybdenum | 6.0–6.5 |
| Copper | 0.5–1.0 |
| Nitrogen | 0.18–0.22 |
| Carbon, max | 0.020 |
| Manganese, max | 1.0 |
| Iron | Balance |
Minimum mechanical properties governing fasteners released to this specification:
| Condition / Temper | Tensile Strength min, psi (MPa) | Yield Strength min, psi (MPa) | Elongation min, % | Hardness |
|---|---|---|---|---|
| Annealed bar | 94 000 (650) | 44 000 (300) | 35 | – |
All standard fastener geometries manufactured at Ananka can be released to ASTM A193 Gr B8UN:
Every batch released to ASTM A193 Gr B8UN is verified by internal and third-party testing.
For technical documentation and quotations, buyers can also review the Ananka Fasteners manufacturing and supply range or contact the team through the fastener enquiry and technical support page.
This datasheet references ASTM A193 Gr B8UN for material and fastener requirements. Related dimensional standards commonly paired with this specification include ASME B18.2.1, DIN 931/933, ISO 4014, BS 3692. The applicable standard edition and purchase requirements should be confirmed for every project.
For ASTM International material and fastener specifications, see the ASTM International standards catalogue. This external reference is provided for standards identification; the purchaser should verify the current edition applicable to the order.
ASTM A193 Gr B8UN chemistry and mechanicals for one or more grades of fastener material. It covers SS 254 SMO.
Ananka Fasteners supplies SS 254 SMO to this specification. See Section 2 above for the complete list.
Bolts / Screws / Studs / Nuts / Washers as manufactured to the geometry standard can be released to ASTM A193 Gr B8UN, manufactured to the corresponding geometry standard.
ASTM A193 Gr B8UN fasteners are commonly manufactured to ASME B18.2.1, DIN 931/933, ISO 4014, BS 3692, depending on the fastener type required.
Yes. For a quotation, provide the required fastener type, material grade, nominal size, dimensional standard, quantity and any inspection or certificate requirements.
Need a fastener released to ASTM A193 Gr B8UN for an industrial project? Send the required fastener type, material grade, size, quantity and certification requirements to Ananka Fasteners. Our team can review the requirement and provide technical and commercial information for standard or custom configurations.
Recommended RFQ details: ASTM A193 Gr B8UN requirement, material grade, fastener type, nominal size, quantity, inspection requirements and EN 10204 certificate requirements where applicable.
