Application of Computer Simulation on Large Size Steam Turbine Casing

摘要

The quality requirements for the steam turbine casing for fossil power plant are extremely high because the operation conditions are severe such as 566°C of the steam temperature and 241.3 bars of pressure. And such conditions are going to much severer direction due to demand of higher efficiency and clean environment. In addition the shape of casting is complicate with many holes and the wall thickness is thin comparing with the huge size. Therefore it is difficult to make defect free casting. The bigger casting, the more possibility of defects. To reflect the real manufacturing condition, the thermal conductivities and heat transfer coefficient(HTC) of molding materials was measured. Modifying casting designs with the aid of computer simulation prior to real pouring, the best design was selected and the casting was poured.