TURBINE SECTION (Cont)

TM 55-2840-254-23

THIRD TURBINE NOZZLE AND SUPPORT. Located between second gas producer disc assembly

and third turbine disc (part of integral shaft assembly). Provides mounting areas

for five thermocouple harness assemblies. Directs hot gases so they hit third

turbine blades most efficiently.

INTEGRAL SHAFT ASSEMBLY. Power shaft and third turbine disc (first power turbine disc) are

welded to form a single unit. Splined to output shaft at front of engine. As hot

gases hit blades, integral shaft assembly turns causing output shaft to turn.

FOURTH TURBINE NOZZLE. Main support for power turbine assembly. Provides mounting area

for exit vane assembly and No. 4 and 5 bearing package. Fits within and mounts

on combustion section. Nozzle vanes direct hot gases leaving integral shaft assem-

bly so they hit fourth turbine disc blades most efficiently.

NO. 4 AND 5 BEARING PACKAGE. Contains twin bearings, and mounts in fourth turbine nozzle.

Supports rear of integral shaft assembly between third and fourth turbine discs.

FOURTH TURBINE DISC ASSEMBLY (SECOND POWER TURBINE DISC). Mounts on rear end of

integral shaft assembly. As hot gases leaving fourth turbine nozzle hit fourth turbine

disc blades, disc assembly turns. Assists integral shaft assembly to turn output shaft.

THERMOCOUPLE HARNESS ASSEMBLIES. Five, with two probes each, positioned around power

turbine assembly. Ten probe ends insert into and mount around third turbine noz-

zle and support. Leeds fit through five guide tubes located around fourth turbine

nozzle and secure to bus bar assembly. Probes made of material which when heated

react by developing a proportional voltage. The average of these voltages is reflected

by cockpit indicator calibrated to read temperature in degrees centigrade.

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