Development of New Advanced Low Pressure End Blades for High Efficiency Steam Turbine

抄録

A low pressure end blade is one of the most important elements in designing the steam turbine, because it determines the performance, the dimension, and the number of casings of the turbine. Applying the state of the art technology to the aerodynamic and mechanical design, Mitsubishi Heavy Industries, Ltd. has been conducting a development program of new advanced low pressure end blades which adopt the ISB (Integral Shroud Blade) structure. A new standard series of these low pressure end blades has already been completed for 50Hz and 60Hz unit application including 3600rpm 45inch titanium blade, 3000rpm 48inch steel blade, and 1500/1800rpm 54inch steel blade which have the largest exhaust annulus area among the same class blades in the world. This paper reports on the up-to-date design technology applied to the new advanced low pressure end blades and on the verification tests to ensure the high efficiency and the reliability of the developed blades.