STEAM TURBINE FLOW PATH Russian patent published in 2007 - IPC F01D9/02 

FIELD: power engineering.

SUBSTANCE: invention is aimed at increasing economy of first non-controlled stages of steam turbines with nozzle steam distribution. According to invention flow path of known steam turbine containing nozzle box assembly accommodating nozzle blades, controlled stage working wheel, diaphragm of first non-controlled stage with fitted-in nozzle blades, working wheel and chamber formed between said wheel of controlled stage and diaphragm of first non-controlled stage is furnished with convex-concave screen installed before nozzle assembly of diaphragm provided with perforations, convex part being arranged opposite to nozzle assembly and pointed into chamber, and concave part is extended in radial direction towards rotor axis. Holes of perforation are of different size. Diameter of holes in part far from rotor axis is at least twice as small as diameter of holes located close to rotor axis.

EFFECT: reduced peripheral nonuniformity of steam flow before nozzle assembly of first non-controlled stage and increased efficiency of non-controlled stage.

2 cl, 1 dwg