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Chrome-molySeamless pipeTG-MG-119 · Rev. 1 · October 2026

ASTM A335 P5 — Chemical Composition & Mechanical Properties

ASTM A335 P5 is a chrome-moly alloy steel grade for seamless pipe (UNS K41545, EN / W.Nr 1.7362). It is also known as 5Cr-½Mo. This sheet summarises its chemical composition limits, minimum mechanical properties, heat treatment and typical service. Teshi Group supplies this grade as a stockist and supplier, and manufactures matching flanges and fittings.

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ASTM A335 P5 at a glance

SpecificationASTM A335 P5
Material familyChrome-moly alloy steel
Product formSeamless pipe
UNS numberK41545
EN / W.Nr equivalent1.7362
Also known as5Cr-½Mo
DocumentTG-MG-119 · Rev. 1 · October 2026

Typical service

Refinery heater and hydrogen piping

Heat treatment

Full or isothermal anneal, or normalised and tempered 675 °C min

Chemical composition of ASTM A335 P5 (weight %)

C0.15 max
Mn0.30–0.60
P0.025 max
S0.025 max
Si0.50 max
Cr4.00–6.00
Mo0.45–0.65

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

Mechanical properties

Tensile strength, min415 MPa
Yield strength (0.2 % offset), min205 MPa
Elongation, min30 %
HardnessNot specified

About chrome-moly alloy steel

Chrome-moly steels are low-alloy steels with 1–9 % chromium and 0.5–1 % molybdenum. Chromium gives oxidation and sulphidation resistance; molybdenum gives creep strength at high temperature. They are the standard choice for steam and hot hydrocarbon service above the carbon-steel range.

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 A335 P5

All equivalents
Standard systemNearest equivalent grade
USA — ASTM / ASMEASTM A335 P5 · ASME SA-335 P5
USA — UNSK41545
Europe — EN designationX11CrMo5 (EN 10216-2)
Europe — W.Nr1.7362
Japan — JISSTPA25 / SFVAF5B
China — GB / NB12Cr5MoI (GB/T 9948) / 1Cr5Mo
China — old GB designation1Cr5Mo
UK — BS (withdrawn)BS 3604 625

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 F5
Wrought butt-weld fittingsASTM A234 WP5 Cl.1

FAQ

ASTM A335 P5: common questions

What is the minimum yield strength of ASTM A335 P5?

205 MPa, with a minimum tensile strength of 415 MPa.

What is the carbon content of ASTM A335 P5?

0.15 max %.

What is the UNS number and EN equivalent of ASTM A335 P5?

UNS K41545; the nearest European designation is W.Nr 1.7362. Equivalents are close but not identical — check the specification if substituting.

How is ASTM A335 P5 heat treated?

Full or isothermal anneal, or normalised and tempered 675 °C min.

What is the Chinese (GB) equivalent of ASTM A335 P5?

The nearest Chinese equivalent is 12Cr5MoI (GB/T 9948) / 1Cr5Mo, formerly 1Cr5Mo. Equivalents are close but not identical — compare chemistry and properties before substituting.

What is the JIS equivalent of ASTM A335 P5?

The nearest Japanese (JIS) equivalent is STPA25 / SFVAF5B.

Does Teshi Group supply ASTM A335 P5?

Teshi Group supplies this grade as a stockist and supplier, and manufactures matching flanges and fittings. Send your size, rating and quantity to info@teshigroup.com for a quotation with EN 10204 3.1 certificates.

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