Power turbine

The power turbine converts the pressurized hot gas flow from the gas generator to mechanical energy, driving a load (in power generation via a gearbox).

Front PT bearing, no.3(HG 4224)

This HG(head group) is containing bearing No3 in the power turbine . And it is a journal tilt pad bearing. Pressure of the supply oil is about 1 bar.
Thermocouples for measuring Bearing No 3 is located in this bearing. This bearing has a housing that this housing will assemble to the HG 5920.

Rear PT bearing, no.4 (HG 4225)

This HG is containing two bearings:
Trust bearing for bearing No 4
Journal bearing for bearing No 4
When rotor start to make 25 megawatt, you will have a huge trust in bearing No4, and for damping this force there is one big trust bearing in this HG. Also in this HG there is transducers for measuring axial displacement of Power turbine rotor And if you look deeper in this HG, you will notify that temperature sensors for bearing No4, is assembled in journal pads of this bearing. This bearing is directly assemble to the HG 5920

PT diffuser (HG 5910)

This HG(head group) is the biggest casing in the Siemens SGT600 gas turbine. And it is main part of the power turbine.
In this casing you have insulations for insulating heat. Both type of sheet metals and soft material.
HG 5910 is basement of T7 thermocouple and bearing No4 vibration sensor. For cooling of guide vane stage 3 in HG 6010, there is one manifold that is belonging to HG 5910.
This HG has two place for handling the gas turbine and also has one fix point that in the site some percent of weight of gas turbine will be in this fix point.

PT inner Casing (HG 5920)

T HG 5920 is the place of assembly of bearing no3 and 4. and also rotor through this HG will assemble. And also this HG is basement of bearing No 3 and 4 vibration transducers. Speed and phase transducers.
This HG with 4 ex center shaft is assembled to HG 5910. During assembly of this HG it important o know that center of this HG its not exactly ot the center of HG 5910.
This HG has both type of sheet metal insulation and soft material.

PT rotor (HG 6000)

One of the most important part of the power turbine is PT rotor. Bearing No 3 and No 4 are sited in this HG. This HG has two disks that are welded to the main shaft. And in this disks, there is hot section blades.
In the end of the rotor there is a coupling that will connect to the flexible coupling of compressor. This rotor its not hollow shaft , so it means that it is very heavy.
Rotor during running of the unit will have axial movement that this movement and force will damp with bearing No4

Guide vane Carrier 3 and 4 (HG 6010)