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BoltingStud bolts / boltingTG-MG-033 · Rev. 1 · October 2026

ASTM A193 B8 Cl.1 — Chemical Composition & Mechanical Properties

ASTM A193 B8 Cl.1 is a bolting & nut grades grade for stud bolts / bolting (UNS S30400, EN / W.Nr 1.4301). It is also known as 304. This sheet summarises its chemical composition limits, minimum mechanical properties, heat treatment and typical service. Teshi Group manufactures stud bolts and nuts in this grade.

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ASTM A193 B8 Cl.1 at a glance

SpecificationASTM A193 B8 Cl.1
Material familyBolting & nut grades
Product formStud bolts / bolting
UNS numberS30400
EN / W.Nr equivalent1.4301
Also known as304
DocumentTG-MG-033 · Rev. 1 · October 2026

Typical service

Corrosion-resistant / cryogenic / high-temperature bolting

Heat treatment

Carbide solution treated

Chemical composition of ASTM A193 B8 Cl.1 (weight %)

C0.08 max
Mn2.00 max
P0.045 max
S0.030 max
Si1.00 max
Cr18.0–20.0
Ni8.0–11.0
Mo—

Single values are maximums unless shown as a range or “min”.

Mechanical properties

Tensile strength, min515 MPa
Yield strength, min205 MPa
Elongation, min30 %
Hardness223 HBW (96 HRB)

About bolting & nut grades

Flange bolting is specified as a stud-bolt grade plus a nut grade. ASTM A193 covers high-temperature bolting (B7, B7M, B16, B8, B8M), A320 covers low-temperature bolting (L7, L7M, L43, B8 classes), A453 covers high-strength austenitic bolting (Grade 660), and A194 covers the nuts (2H, 2HM, 4, 7, 8, 8M).

Reference information compiled from the published standard for convenience. It does not replace the current edition of the governing standard, which takes precedence. Verify critical dimensions and properties before design, purchase or fabrication. Teshi Engineers & Sales Promoters (P) Ltd accepts no liability for errors or omissions.

International equivalents of ASTM A193 B8 Cl.1

All equivalents
Standard systemNearest equivalent grade
USA — ASTM / ASMEASTM A193 B8 Cl.1 · ASME SA-193 B8 Cl.1
USA — UNSS30400
Europe — EN designationX5CrNi18-10
Europe — W.Nr1.4301
Japan — JISSUS304 / SUSF304
China — GB / NBS30408 (06Cr19Ni10)
China — old GB designation0Cr18Ni9
India — ISX04Cr19Ni9 (IS 6911)
UK — BS (withdrawn)304S31

Equivalents are the nearest commonly cited grades. Chemistry, mechanical properties and testing differ between standards — compare them before substituting one for another.

Same alloy in other product forms

Product formSpecification / grade
Forged flanges & fittingsASTM A182 F304
Seamless pipe (seamless & welded)ASTM A312 TP304
Wrought butt-weld fittingsASTM A403 WP304
Heavy hex nutsASTM A194 8

FAQ

ASTM A193 B8 Cl.1: common questions

What is the minimum yield strength of ASTM A193 B8 Cl.1?

205 MPa, with a minimum tensile strength of 515 MPa.

What is the carbon content of ASTM A193 B8 Cl.1?

0.08 max %.

What is the UNS number and EN equivalent of ASTM A193 B8 Cl.1?

UNS S30400; the nearest European designation is W.Nr 1.4301. Equivalents are close but not identical — check the specification if substituting.

How is ASTM A193 B8 Cl.1 heat treated?

Carbide solution treated.

What is the Chinese (GB) equivalent of ASTM A193 B8 Cl.1?

The nearest Chinese equivalent is S30408 (06Cr19Ni10), formerly 0Cr18Ni9. Equivalents are close but not identical — compare chemistry and properties before substituting.

What is the JIS equivalent of ASTM A193 B8 Cl.1?

The nearest Japanese (JIS) equivalent is SUS304 / SUSF304.

Does Teshi Group supply ASTM A193 B8 Cl.1?

Teshi Group manufactures stud bolts and nuts in this grade. Send your size, rating and quantity to info@teshigroup.com for a quotation with EN 10204 3.1 certificates.

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