ISO 9001:2015IBR ApprovedEstablished 1971Full Material Traceability
GroupRequest a quote
BoltingStud bolts / boltingTG-MG-034 · Rev. 1 · October 2026

ASTM A193 B8M Cl.1 — Chemical Composition & Mechanical Properties

ASTM A193 B8M Cl.1 is a bolting & nut grades grade for stud bolts / bolting (UNS S31600, EN / W.Nr 1.4401). It is also known as 316. 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.

Download PDF Request a quoteA4 · Teshi Group document TG-MG-034 · © Teshi Group · controlled document

ASTM A193 B8M Cl.1 at a glance

SpecificationASTM A193 B8M Cl.1
Material familyBolting & nut grades
Product formStud bolts / bolting
UNS numberS31600
EN / W.Nr equivalent1.4401
Also known as316
DocumentTG-MG-034 · Rev. 1 · October 2026

Typical service

Corrosion-resistant bolting (316)

Heat treatment

Carbide solution treated

Chemical composition of ASTM A193 B8M Cl.1 (weight %)

C0.08 max
Mn2.00 max
P0.045 max
S0.030 max
Si1.00 max
Cr16.0–18.0
Ni10.0–14.0
Mo2.00–3.00

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 B8M Cl.1

All equivalents
Standard systemNearest equivalent grade
USA — ASTM / ASMEASTM A193 B8M Cl.1 · ASME SA-193 B8M Cl.1
USA — UNSS31600
Europe — EN designationX5CrNiMo17-12-2
Europe — W.Nr1.4401
Japan — JISSUS316 / SUSF316
China — GB / NBS31608 (06Cr17Ni12Mo2)
China — old GB designation0Cr17Ni12Mo2
India — ISX04Cr17Ni12Mo2 (IS 6911)
UK — BS (withdrawn)316S31

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 F316
Seamless pipe (seamless & welded)ASTM A312 TP316
Wrought butt-weld fittingsASTM A403 WP316
Heavy hex nutsASTM A194 8M

FAQ

ASTM A193 B8M Cl.1: common questions

What is the minimum yield strength of ASTM A193 B8M Cl.1?

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

What is the carbon content of ASTM A193 B8M Cl.1?

0.08 max %.

What is the UNS number and EN equivalent of ASTM A193 B8M Cl.1?

UNS S31600; the nearest European designation is W.Nr 1.4401. Equivalents are close but not identical — check the specification if substituting.

How is ASTM A193 B8M Cl.1 heat treated?

Carbide solution treated.

What is the Chinese (GB) equivalent of ASTM A193 B8M Cl.1?

The nearest Chinese equivalent is S31608 (06Cr17Ni12Mo2), formerly 0Cr17Ni12Mo2. Equivalents are close but not identical — compare chemistry and properties before substituting.

What is the JIS equivalent of ASTM A193 B8M Cl.1?

The nearest Japanese (JIS) equivalent is SUS316 / SUSF316.

Does Teshi Group supply ASTM A193 B8M 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.

Ready to build to spec?

Share your drawing, bill of materials or technical requirements with the Teshi team.