Construction boiler steel 24CrMoV5-5, 1.7733, 28CDV5 for power engineering at elevated temperatures for turbine parts and boilers operating to 540 ℃ according to DIN 17240.
| Standards | Steel Grades | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Chemical Composition % | ||||||||||
| C: | Mn: | Si: | P: | S: | Cr: | Mo: | Ni: | V: | Cu: | |
| PN | 26H2MF | |||||||||
| 0.22 - 0.30 | 0.3 - 0.6 | 0.3 - 0.5 | <0.035 | <0.035 | 1.5 - 1.8 | 0.6 - 0.8 | <0.3 | 0.2 - 0.3 | <0.25 | |
| DIN | 24CrMoV5-5 - 24 CrMoV 5-5 - 1.7733 | |||||||||
| 0.20 - 0.28 | 0.3 - 0.6 | 0.15 - 0.35 | <0.035 | <0.035 | 1.2 - 1.5 | 0.5 - 0.6 | <0.6 | 0.15 - 0.25 | - | |
| ČSN STN | ČSN 15 320 - ČSN 15320 - ČSN 415320 - STN 415320 | |||||||||
| 0.20 - 0.28 | 0.5 - 0.8 | 0.17 - 0.37 | <0.035 | <0.035 | 1.1 - 1.4 | 0.55 - 0.75 | - | 0.15 - 0.30 | - | |
| GB/T | 25Cr2Mo1VA - 25Cr2MoVA - 25CrMoVA | |||||||||
| 0.22 - 0.29 | 0.4 - 0.7 | 0.17 - 0.37 | <0.025 | <0.025 | 1.5 - 1.8 | 0.25 - 0.35 | <0.3 | 0.15 - 0.30 | <0.25 | |
| MSZ | MCrMoV | |||||||||
| 0.17 - 0.25 | 0.5 - 0.8 | 0.17 - 0.37 | <0.035 | <0.035 | 1.2 - 1.5 | 0.8 - 1.0 | 0.3 - 0.6 | 0.30 - 0.45 | <0.30 | |
| AFNOR | 28CDV5 - 28 CDV 5 | |||||||||
| 0.25 - 0.30 | <0.80 | <0.60 | <0.040 | <0.035 | 1.0 - 1.5 | 0.6 - 0.8 | - | 0.25 - 0.35 | - | |
| PN | 24H2MF | |||||||||
| 0.20 - 0.30 | 0.5 - 0.8 | 0.17 - 0.37 | <0.030 | <0.030 | 2.10 - 2.50 | 0.9 - 1.2 | - | 0.3 - 0.6 | - | |
| PN | 23H2MF | |||||||||
| 0.21 - 0.29 | 0.35 - 0.70 | 0.25 - 0.50 | <0.030 | <0.025 | 1.40 - 1.80 | 0.90 - 1.10 | <0.3 | 0.20 - 0.30 | <0.20 | |
| OST | 25Ch2M1F - 25Х2М1Ф | |||||||||
| 0.22 - 0.29 | 0.40 - 0.70 | 0.17 - 0.37 | <0.030 | <0.025 | 2.10 - 2.60 | 0.90 - 1.10 | <0.3 | 0.30 - 0.50 | <0.30 | |
24CrMoV5-5, 1.7733 - specification
CrMoV chrome-molybdenum-vanadium ferrite medium alloy steel, replaced by 23H2MF creep resistant grade, designed to operate at elevated temperatures in boilers and turbine parts up to 540 ℃.
Produced in the form of forgings, rotor shafts, turbines and boilers, rolled and drawn bars, bolted nuts and struts in normalized and tempered or heat-treated state.
26H2MF grades are used for turbine rotor shafts, bolts, large forgings shafts, nuts, boiler parts, boiler and steam turbine couplings, spacers, fittings, covers, pinned bolts, tanks, forged flanges, welded tubes, and turbine blades.
Steel is not suitable for welding. In exceptional cases it can joined by electric welding, resistance welding, or friction bonding.
Mechanical properties of samples in heat-treated state
- Tensile strength Rm = 70 - 85 kG/mm2
- Yield pointności Renbsp;= > 55 kG/mm2
- Elongation A5nbsp;= > 17%
- Resilience by Mesnager samples KM > 9 kGm/cm2
- Hardness 201 - 208 HB
Mechanical properties at elevated temperatures
| Temperatures | 200℃ | 250℃ | 300℃ | 350℃ | 400℃ | 450℃ | 500℃ |
|---|---|---|---|---|---|---|---|
| Yield point Re (kG/mm2) | 50 | 48 | 46 | 44 | 41 | 38 | 35 |
Creep limit and creep strength of 24CrMoV5-5, 1.7733 steel in normalized and tempered condition
| Property (MPa) | Temperatures | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 420℃ | 430℃ | 440℃ | 450℃ | 460℃ | 470℃ | 480℃ | 490℃ | 500℃ | 510℃ | 520℃ | 530℃ | 540℃ | 550℃ | |
| R1/10 000 | 337 | 328 | 316 | 303 | 286 | 268 | 245 | 219 | 193 | 172 | 151 | 131 | 112 | 92 |
| R1/100 000 | 286 | 273 | 257 | 239 | 218 | 195 | 172 | 149 | 128 | 111 | 96 | 80 | 67 | 55 |
| Rz/10 000 | 461 | 443 | 426 | 404 | 380 | 354 | 325 | 290 | 257 | 230 | 206 | 181 | 160 | 138 |
| Rz/100 000 | 386 | 367 | 345 | 322 | 297 | 266 | 243 | 215 | 183 | 156 | 131 | 110 | 92 | 74 |
Steel heat treatment:
- Normalization with cooling in calm air at 900 - 930 ℃
- Relief annealing in the temperature range 480 - 650℃
- Softening at 680 - 720℃
- Hardening with cooling in oil or air at the temperature of 880 - 990 ℃
- 2 hours tempering in the temperature range 600 - 700℃
In this grade the company provides:
- Hot-rolled bars 24CrMoV5-5, 1.7733
- Forged bars and flat bars 24CrMoV5-5, 1.7733
- Forgings 24CrMoV5-5, 1.7733
Other indications and equivalents of 26H2MF steel:
24CrMoV5-5, 24 CrMoV 5-5, 24CrMoV5.5, 24 CrMoV 5.5, 1.7733, 7733, ČSN 15 320, ČSN 15320, ČSN 415320, STN 415320, 25Cr2Mo1VA, 25Cr2MoVA, 25CrMoVA