KNR70S

1 source records. Standards, editions and conditions are presented separately; matching grade names do not establish interchangeability.

Refer to each source for mass fractions and analysis type. Missing values are not treated as 0. Manufacturer typical values, standard guarantees and measured heat results must remain separate. Use the material selector for calculations and condition selection.

Open condition selection, comparison and carbon-equivalent tools for KNR70S →

KNR70S · Kobe Steel manufacturer specification (section 6-18)

Chemical composition source verified; this does not verify every standard clause, actual supply or measured heat results

Material category: Carbon steel
Subcategory: Free-cutting bar products for use without quenching and tempering
Material form: Bars
Original record status: Manufacturer source verified
Document edition: Publication edition not stated in the document
Document title: Wire rod and bar specification tables
Table / clause: 6-18
PDF page references: 35
Unit: Mass fraction (wt%)
Manufacturer: Kobe Steel

Carbon-equivalent reference

Estimate from manufacturer-published ranges, not a standard guarantee or measured heat result; formula applicability requires review against the application and process.

IIW / CEV：0.5033–0.7033Known-element contribution; incomplete value; missing Mo CEV = C + Mn/6 + (Cr + Mo + V)/5 + (Ni + Cu)/15; an engineering estimate of welding cold-cracking susceptibility for carbon and low-alloy steels.

Pcm（Ito–Bessyo）：0.3450–0.4625Known-element contribution; incomplete value; missing Mo, B Pcm = C + Si/30 + (Mn + Cu + Cr)/20 + Ni/60 + Mo/15 + V/10 + 5B; mainly used for low-carbon low-alloy steels, particularly modern low-carbon pipeline steels; more relevant when C is approximately no higher than 0.11%.

CET：0.3900–0.5075Known-element contribution; incomplete value; missing Mo CET = C + (Mn + Mo)/10 + (Cr + Cu)/20 + Ni/40; used in welding preheat assessment for ferritic steels, subject to the applicability conditions of EN 1011-2.

Composition

Element	Composition requirement
C	0.27 ～ 0.33
Si	0.15 ～ 0.35
Mn	1.1 ～ 1.4
P	≤ 0.03 (lower limit not stated)
S	≤ 0.035 (lower limit not stated)
Cu	≤ 0.25 (lower limit not stated)
Ni	≤ 0.2 (lower limit not stated)
Cr	0.2 ～ 0.4
V	0.05 ～ 0.15

Applicability and limitations

Original composition for free-cutting bars used without quenching and tempering in the Kobe Steel catalogue, section 6-18 (PDF page 35), mass fractions wt%; This is not the original JIS/SAE standard. Actual supply and process applicability require separate confirmation.

Composition conditions

Original table in section 6-18, mass percent; Dashes and unlisted elements are not entered as zero.
This page also contains mechanical reference values grouped by size; They are not included as unconditional mechanical-property values.
The manufacturer catalogue does not identify the publication edition; Catalogue information does not establish current supply dimensions.

Verification notes

Chemical values checked cell by cell against the manufacturer original table; columns joined during extraction in Section 6-17 were additionally checked manually against the original image.