Repair of Cracked 150 MW High-Pressure Steam Turbine Rotor Coupling

Abstract

Abstract A 150 MW high-pressure steam turbine rotor in Philippine experienced cracking in coupling area. The root cause of crack failure was investigated, and it was revealed that alignment setup design from original equipment manufacturer (OEM) contributed to the failure. The cracked coupling was restored by weld build up back to original dimension and new alignment target was recalculated and the result was counterchecked by finite element analysis (FEA) method to verify the stress level reduction.