Page 56 - Steam Turbines Design, Applications, and Rerating

Turbine Casing and Major Stationary Components 37

Nozzle
Rings

Intermediate
Pressure
Diaphragms

Low-
Pressure
Diaphragms

Figure 2.10 Nozzle rings and diaphragms direct steam onto the rotating blades (buckets)
of a turbine. (Elliott Company, Jeannette, Pa.)

■ Separates the turbine into a number of separate pressure stages of
successively lower pressure
■ Contains the nozzles that accelerate and direct the steam jet into
and through the blading of the next succeeding rotating wheel
■ Retains the packing through which passes the shaft containing the
wheels of each stage

The nozzles contained in the diaphragms vary in size and passage
area from stage to stage to efficiently handle the steam volume encoun-
tered at the various pressure levels throughout the turbine.