Turbine material details
The Turbine is operated in hi temperature, pressure ,speed and erosion environment. So materials need are for Cr, Ni and Mo, V-based alloys for operation at 537 to 600°C with (i) adequate creep rupture strength; (ii) ability to cast them into the required size and shape, and to inspect for defects; and (iii) ability to perform initial fabrication welding (on cast or wrought forms, including dissimilar metal welds), and to make repair welds on aged material. It is observed that percentage of Cr and Ni are increased to improve the quality of steel for the different parts of the turbine. Component 566°C 620°C 700°C 760°C Casings/Shells CrMoV (cast) 9-10%Cr(W) CF8C-Plus CCA617 (valves; steam 10CrMoVNb 12CrW(Co) CCA617 Inconel 740 chests; nozzle box; CrMoWVNbN Inconel 625 ...