Part 1 - Inside a GE LM6000 (CF6-80C2) Gas Turbine
The GE (General Electric) LM6000 is a turboshaft aeroderivative gas turbine engine. The LM6000 is derived from the CF6-80C2 aircraft turbofan which is used in Boeing 747-400, McDonnell Douglas MD-11, Airbus A300 and Airbus A310 type airplanes.
The declared performance data (as provided and published by GE) can be seen in the table below. For simple cycle operations;
and for combined cycle in 1+1 configuration (ie. a single gas turbine + a single steam turbine) as follows,
All turbine performance data provided are at ISO conditions (ISO 3977-2:1997 Gas turbines — Procurement — Part 2: Standard reference conditions and ratings) , which are as follows;
Ambient Temperature 15oC
Relative humidity %60
Ambient pressure at sea level (1013.25 hPA or 29.92 inches of Mercury)
Please also note that actual performance of the engine will vary with project-specific conditions and fuel specifications.
A general overview of the LM6000 turbine can be seen below with the main components as ;
LPC - Low pressure compressor (5 stages) with a 2.4 : 1 compression ratio
HPC - High pressure compressor (14 stages) with a 12 :1 compression ration
Combustion chamber (Combustor)
HPT - High pressure turbine (2 stages)
LPT - Low pressure turbine (5 stages)
It is a twin spool design with dual rotor;
The LP (low pressure) rotor consists of the 5-stage LPC and the 5-stage LPT that drives it.
The HP (high pressure) rotor consists of the 14-stage HPC and the 2-stage HPT that drives it.
Below is a schematic of the dual rotor structure.
A detailed cross section of the LM6000 can be seen below
Below is a dismanteled photo showing the Bleed Air duct and the LP shaft. The accesory gear box and hydraulic started pump can also be seen in this photo. The grayish colored duct is the bleed air duct (2.4)
The following photos are related to a dismanteled HPC (High pressure compressor) with respective definitions and descriptions. As mentioned earlier the HPC is composed of 14 stages of compressor blades mounted on the rotor, and vanes mounted on the external stator casing. The number of blades per stage are as follows ;
HPC STG1 - 36 nos. of blades
HPC STG2 - 26 nos. of blades
HPC STG3 - 42 nos. of blades
HPC STG4 - 45 nos. of blades
HPC STG5 - 48 nos. of blades
HPC STG6 - 54 nos. of blades
HPC STG7 - 56 nos. of blades
HPC STG8 - 64 nos. of blades
HPC STG9 - 66 nos. of blades
HPC STG10 - 66 nos. of blades
HPC STG11 - 76 nos. of blades
HPC STG12 - 76 nos. of blades
HPC STG13 - 76 nos of blades and
HPC STG 14 - 76 nos. of blades,
making a total of 807 blades for the HPC section and 864 vanes on the HPC stator.
Below is a photo from a damaged engine with all HPC blades removed and ready for an inspection
Below is the disc for HPC STG1 - Blades
Below is the disc for HPC STG2 - Blades
Below is the spool for the HPC STG3 - STG9 blades
And finally spool for HPC STG10 - STG14 blades can be seen below.
The stator for the HPC naked with all components removed can be seen in the photo below.
The inside of this stator case with the vanes (some of these vanes are rotatable and some of the vanes are fixed) can be seen below.
A typical HPC blade showing the leading and the trailing edges and the dove tail region.
I will continue with Part2 to show more details from the other relevant sections of the CF6-80C2 gas turbine . The next update will be from the combustor and the HPT (high pressure turbine) So please keep an eye on the website and subscribe for further updates.