Specifications
Surface Treatments
Certifications
- ISO 9001 - 2015 Certified
- PED 2014/68/EC
- NACE MR0175/ISO 15156-2
- NORSOK M-650
- DFAR
- MERKBLATT AD 2000 W2/W7/W10
Durehete Grades — 1055, 950, 900
Three Cr-Mo-V-Ti-B bolting steels covering the 540–580°C high-temperature envelope. Each grade trades creep-rupture strength against ductility. All three are supplied as Q+T forged bar to EN 10269 with full creep-rupture data per VdTUV-Werkstoffblatt 350.
Durehete 1055 (Alloy T41 / 1.7729)
Highest-temperature grade in the family, qualified to ~568°C / 1055°F continuous service. EN designation 20CrMoVTiB4-10. Used for HP/IP steam-turbine casing bolts and supercritical main-steam bolting.
Durehete 950 (Alloy T31 / 1.7711)
Mid-range Cr-Mo-V grade, qualified to ~540°C continuous service. EN designation 40CrMoV4-6. Used for IP and LP turbine casing bolts and gas-turbine compressor bolting.
Durehete 900 (Alloy T22 / 42CrMoV5-6)
Entry-tier Cr-Mo-V grade for moderate-temperature service to ~500°C. Used for steam-turbine LP casing bolting and refinery furnace stud bolts where 1055/950 specifications are not contractually required.
For procurement or technical questions on any of the above, contact TorqBolt QA-QC or WhatsApp +91-22-66157017. Related: Durehete 1055 (Alloy T41 / 1.7729) · Durehete 950 (Alloy T31 / 1.7711) · Durehete 900 (Alloy T22 / 42CrMoV5-6).