High-Pressure Turbine Shaft for Hydroelectric Plant
CNC & WeldingTask: Design and manufacture a monolithic high-pressure turbine shaft capable of withstanding extreme torsional stress and corrosion in a freshwater environment. The client required a 30% increase in fatigue life over previous designs. Approach: Our metallurgical team developed a proprietary nickel-chromium-molybdenum alloy (SAM-NCM-7). We utilized 5-axis CNC milling for precise forging die creation and employed submerged arc welding for joining the forged segments under a controlled argon atmosphere. Implementation: The shaft was machined from a single forged billet, with internal cooling channels fabricated via deep-hole drilling. Post-weld heat treatment and cryogenic stabilization were applied to enhance grain structure. Result: The final component exceeded the fatigue life target by 35% and passed all hydrostatic and non-destructive tests. The project included a full digital twin for predictive maintenance.