21CrMoV5-7 — DIN 2510 material code GA
21CrMoV5-7 (material number 1.7709) is a chromium-molybdenum-vanadium low-alloy steel listed in DIN 267-13 Table 2 for high-temperature bolting service. Supplied quenched and tempered (+QT), hardness 225 to 272 HV. Maximum short-term service 500 °C; maximum long-term service 550 °C. Suited to creep-resistant bolting in steam-turbine and power-plant flanged joints.
DIN 267-13 properties
| Material symbol | GA |
|---|---|
| Material number | 1.7709 |
| Material name | 21CrMoV5-7 |
| Heat treatment condition | +QT (quenched and tempered) |
| Hardness range (HV) | 225 to 272 |
| Maximum short-term service temperature | 500 °C |
| Maximum long-term service temperature | 550 °C |
Source: DIN 267-13:2007-05, Table 2 (Steels and nickel alloys as in DIN EN 10269 for high and low service temperatures).
Applicable DIN 2510 parts
21CrMoV5-7 (code GA) is the high-temperature material for DIN 2510 Part 6 cap nuts and is used across Parts 5, 6, and 7.
- DIN 2510 Part 6: Cap Nuts (Type AF, BF)
- DIN 2510 Part 5: Hexagon Nuts (Type NF, TF)
- DIN 2510 Part 7: Extension Sleeves (Type D, E)
Companion DIN 2510 materials
- 24CrMo5: code G per DIN 2510 designation
- 25CrMo4: code KG per DIN 267-13
- 1.4980: code SD per DIN 267-13 (X6NiCrTiMoVB25-15-2 / A-286)
For mill test certificates (EN 10204 3.1 or 3.2) and quoted lead time on DIN 2510 components in 21CrMoV5-7, email info@torqbolt.com or WhatsApp +91-22-66157017.