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- MERKBLATT AD 2000 W2/W7/W10
EN 10269 equivalents across the major international bolting standards: the European Norm grades cross-reference to ASTM (US), AFNOR (France), Polish PN, JIS (Japan), GOST (Russia) and Chinese GB equivalents. The cross-reference table is the procurement bridge for dual-certified material orders and for re-qualification of legacy bolting on retrofit projects.
Request a Quote on EN 10269 Equivalents (Cross-Reference Master Table) Bolting Stock and Fasteners
EN 10269 specifies eight Cr-Mo-V and stainless bolting grades for elevated-temperature fastener service. Each grade has a near-equivalent in the ASTM, AFNOR and Polish PN systems. The cross-references are not always exact substitutes (chemistry windows differ slightly), so dual-certification from the same heat lot is the cleanest procurement path when both designations are required on the same project.
| EN 10269 | Werkstoff | ASTM A193 | AFNOR (NF) | Polish PN |
|---|---|---|---|---|
| 21CrMoV5-7 | 1.7709 | B16 (close) | 20CDV5.7 | 21HMF |
| 21CrMoV5-11 | 1.8070 | B16 (heavier section) | 21CDV5.11 | 20HMF |
| 24CrMoV5-5 | 1.7733 | B16 sub-set | 24CDV5.5 | 24HMF |
| 42CrMo4 | 1.7225 | B7 | 42CD4 | 40HM |
| 40CrMoV4-6 (Durehete 950) | 1.7711 | B16 sub-set | n/a | n/a |
| 20CrMoVTiB4-10 (Durehete 1055) | 1.7729 | n/a direct (above B16 envelope) | n/a | 20HMFTB |
| X22CrMoV12-1 (martensitic stainless) | 1.4923 | B6 (close) | X20CDV12 | n/a |
| X6CrNi18-10 (austenitic) | 1.4301 | B8 (close) | Z6CN18.10 | 0H18N9 |
For European procurement specifying EN 10269 21CrMoV5-7: order the material with EN 10269 21CrMoV5-7 chemistry compliance. For US procurement specifying ASTM A193 Grade B16: order with dual-cert to EN 10269 21CrMoV5-7 plus ASTM A193 Grade B16 if cross-procurement is anticipated. The dual-cert protects against re-qualification if the project is re-spec'd mid-build.
Detail per neighboring grade: vs ASTM A193 B16 (closest US cousin) · vs ASTM A193 B7 (carbon-Mo, no V) · vs ASTM A193 B8 (austenitic) · vs 21CrMoV5-11 (heavier-section variant) · vs 24CrMoV5-5 (lower-temp neighbor) · vs Durehete 1055 (premium Ti+B microalloyed) · vs 20CDV5.7 AFNOR · vs 21HMF Polish PN · vs 42CrMo4.
21CrMoV5-7 (Werkstoff 1.7709) chemistry is fixed within a tight Cr-Mo-V Q+T window to EN 10269. Carbon at 0.17 to 0.25 percent gives the Q+T hardenability backbone without over-hardening for the secondary temper. Chromium at 1.20 to 1.50 percent provides through-thickness hardenability and stabilises the carbide network for creep. Molybdenum at 0.55 to 0.80 percent suppresses temper embrittlement and contributes to the secondary hardening peak. Vanadium at 0.20 to 0.35 percent drives the V4C3 precipitation during the 680 to 740 deg C temper that locks in the creep envelope. The chemistry window is shared with the AFNOR 20CDV5.7 (French) and Polish 21HMF designations.
| Element | Min % | Max % | Role |
|---|---|---|---|
| Carbon (C) | 0.17 | 0.25 | Q+T hardenability |
| Silicon (Si) | — | 0.40 | Deoxidation |
| Manganese (Mn) | 0.40 | 0.80 | Hardenability + solid-solution |
| Phosphorus (P) | — | 0.030 | Tramp limit for toughness |
| Sulphur (S) | — | 0.030 | Tramp limit |
| Chromium (Cr) | 1.20 | 1.50 | Hardenability + creep |
| Molybdenum (Mo) | 0.55 | 0.80 | Secondary hardening |
| Vanadium (V) | 0.20 | 0.35 | V4C3 carbide strengthening |
| Nickel (Ni) | — | 0.60 | Residual |
| Aluminium (Al) | — | 0.030 | Grain refinement |
The defining value-prop of 21CrMoV5-7 is the secondary-hardening creep envelope driven by V4C3 carbide precipitation. The fine V4C3 dispersion formed during the 680 to 740 deg C temper pins dislocation motion during long-time elevated-temperature service. The result is a 100,000-hour stress-rupture envelope to EN 10269 Annex A of approximately 340 MPa at 500 deg C, 290 MPa at 525 deg C, 260 MPa at 540 deg C, and 180 MPa at 550 deg C. Above 550 deg C the V4C3 coarsens faster than the design can tolerate; this is the boundary where the design must step up to Durehete 1055 (Alloy T41 / 1.7729) with Ti+B microalloying for grain-boundary pinning that extends the envelope to 568 deg C continuous service.
| Temperature | 100,000 h rupture stress | 1 percent creep strain at 100,000 h |
|---|---|---|
| 450 deg C | ~470 MPa | ~380 MPa |
| 500 deg C | ~340 MPa | ~280 MPa |
| 525 deg C | ~290 MPa | ~235 MPa |
| 540 deg C | ~260 MPa | ~210 MPa |
| 550 deg C | ~180 MPa | ~150 MPa |
The standard cycle for 21CrMoV5-7 is austenitisation at 880 to 940 deg C with hold time of 1 hour per 25 mm section, followed by oil quench. The temper is at 680 to 740 deg C for minimum 2 hours then air cool. The temper temperature is chosen to land on the secondary-hardening peak; below 660 deg C the V4C3 carbide precipitation is under-developed and long-term creep performance suffers; above 750 deg C the carbides over-coarsen and the room-temperature yield drops below the EN 10269 floor of 550 MPa. For heavily machined fastener blanks where dimensional stability matters, a stress relief at 50 deg C below the final temper is recommended after machining.
21CrMoV5-7 is welded with matched-composition Cr-Mo-V low-hydrogen filler (AWS A5.5 E9018-B3L for SMAW, AWS A5.28 ER90S-B3L for GTAW, AWS A5.23 EB3 for SAW) under preheat 200 to 300 deg C and diffusible-hydrogen cap of 5 ml per 100 g deposited. Post-weld heat treatment at 690 to 720 deg C for 1 hour per 25 mm joint thickness, minimum 2 hours, slow furnace cool to 300 deg C then air cool. The PWHT re-tempers the heat-affected zone and restores creep performance. Hardness traverse across weld plus HAZ plus parent metal verifies the PWHT achieved the intended tempering; HAZ hardness must not exceed 320 HBW.
21CrMoV5-7 sits between ASTM A193 Grade B7 (carbon-Mo only, no vanadium, capped at 450 deg C) and Durehete 1055 (Alloy T41 with Ti+B microalloying, 568 deg C envelope). Its direct US cousin is ASTM A193 Grade B16, with overlapping Cr-Mo-V chemistry and similar 540 deg C service envelope. Dual-certification to EN 10269 21CrMoV5-7 plus ASTM A193 B16 from the same heat lot is standard practice on cross-procurement projects.
| Grade | Chemistry | Max temp | When to specify |
|---|---|---|---|
| ASTM A193 B7 | Cr-Mo (no V) | 450 deg C | Lower-temp bolting where cost matters |
| 21CrMoV5-7 | Cr-Mo-V Q+T | 550 deg C | Workhorse mid-tier turbine + power + refinery |
| ASTM A193 B16 | Cr-Mo-V Q+T | 540 deg C | US dual-cert cousin |
| 21CrMoV5-11 (1.8070) | Cr-Mo-V Q+T higher Mo | 550 deg C | Heavier section (OD above 200 mm) |
| Durehete 1055 (Alloy T41 / 1.7729) | Cr-Mo-V-Ti-B | 568 deg C | HP turbine + supercritical + USC |
Q. How exact are the EN 10269 to ASTM A193 cross-references?
Close but not exact. EN 10269 chemistry windows are typically tighter than the ASTM A193 windows. Chemistry that meets EN 10269 generally meets ASTM A193, but the reverse is not always true. Dual-certified material from the same heat lot is the cleanest procurement path.
Q. Is there a single AFNOR or NF designation equivalent to 21CrMoV5-7?
Yes. AFNOR 20CDV5.7 per NF A35-559 is the direct French equivalent of EN 10269 21CrMoV5-7. The chemistry windows are essentially identical with minor wording differences in the standard text.
Q. What is the Polish PN designation for 21CrMoV5-7?
Polish PN 21HMF per PN-89/H-84030. The 21HMF designation is widely used in Eastern European power-plant procurement (Polish, Czech, Slovak boiler and turbine bolting).
Q. Do you supply material with simultaneous EN, ASTM and AFNOR certification?
Yes. Triple-certification on call-out documents simultaneous compliance to EN 10269 21CrMoV5-7, ASTM A193 Grade B16, and AFNOR 20CDV5.7 for international projects that cross multiple jurisdictions.
Related standards: EN 10269 · EN 10278 · VdTUV Wb 350 · ASTM A193. Properties pages: Chemistry · Mechanicals · Heat Treatment · Hardness · Creep-Rupture. Back to the 21CrMoV5-7 Alloy Hub.