Steam turbine nozzle diaphragm

Abstract

Abstract PURPOSE: To improve the dimensional accuracy of an area of steam passageway and a performance of a turbine, further, to reduce a cost therefor by a method wherein a stator blade, consisting of a nozzle plate and a partition plate integral therewith, and inner and outer rings of a diaphragm are cast together and are secured to each other. CONSTITUTION: A stator blade 31 is made by a precision casting to cast a nozzle plate and a partition plate integrally. The stator blades 31 are arranged in a casting sandmold and a molten cast iron or a molten cast steel is poured into cavities in the sandmold which are formed into configurations of a diaphragm inner ring 32 and a diaphragm outer ring 33 to constitute a nozzle by securing the stator blades 31 to the rings by internal-chill casting. Thus, there is no portion to be welded, therefore, a shrinkage due to the welding will never be caused and a dimensional accuracy of an area for a steam passageway is improved which, in turn, can improve a performance of a turbine. Also, connection with different materials may be facilitated and man- hours therefor may be reduced. COPYRIGHT: (C)1981,JPO&Japio

Inventors

• 👤 Masaki Matsuda
• 👤 Jiro Koike

Bibliographic Details