Turbine module for a gas turbine engine

1. A turbine module for a gas turbine engine comprising at least one turbine disk and a disk-shaped component mounted on the at least one turbine disk upstream relative to a gas flow, said module being configured to be assembled to a compressor of said engine, wherein the component is preassembled to the turbine disk, before the module is assembled to the compressor, by bolting to an attachment flange fixedly attached to the turbine disk, wherein bolts for attaching the disk-shaped component have a specific head which differs from the heads of bolts for attaching the compressor.

2. The module as claimed in claim 1 , wherein said attachment flange is configured to assemble the module to said compressor.

3. The module as claimed in claim 2 wherein the disk-shaped component is disk-shaped with a wheel center between its hub and its periphery, and is mounted onto said attachment flange by a first plurality of bolts through a first plurality of orifices drilled in the wheel center, wherein a second plurality of orifices are made in the wheel center for the assembly by a second plurality of bolts of the turbine module to the compressor.

4. The module as claimed in claim 3 , wherein the disk-shaped component has drillings in the wheel center corresponding to said first and second pluralities of orifices and capable of receiving said first plurality of bolts for fully preassembling said disk-shaped component to said turbine disk or the second plurality of bolts for assembling said module to said compressor.

5. The module as claimed in claim 3 , wherein the first plurality of bolts for fully preassembling said disk-shaped component to said turbine disk are held by a first plurality of nuts swaged onto the attachment flange, on a downstream side, and wherein said second plurality of bolts are held by a second plurality of nuts for assembling the module to the compressor.

6. The module as claimed in claim 5 , wherein the first plurality of nuts and the second plurality of nuts are identical.

7. The module as claimed in claim 1 , wherein the disk-shaped component is fully preassembled to said flange by a first plurality of bolts numbering between 2 and 8 distributed over the circumference.

8. The module as claimed in claim 1 , comprising an upstream balancing device placed on said disk-shaped component independently of the attachment flange.

9. A turbine module for a gas turbine engine comprising at least one turbine disk and a disk-shaped component mounted on the at least one turbine disk upstream relative to a gas flow, said module being configured to be assembled to a compressor of said engine, wherein the component is preassembled to the turbine disk, before the module is assembled to the compressor, by bolting to an attachment flange fixedly attached to the turbine disk, wherein the component is a disk supporting labyrinth seal elements.

10. A compressor associated with the module as claimed in claim 9 to form a gas turbine engine, comprising a downstream flange configured to attach to the module, said downstream flange defining housings made for heads of the first plurality of bolts already in place on the fully assembled module.

11. A gas engine comprising:

a turbine module for a gas turbine engine comprising at least one turbine disk and a disk-shaped component mounted on the at least one turbine disk upstream relative to a gas flow, said module being configured to be assembled to a compressor of said engine, wherein the disk-shaped component is preassembled to the turbine disk, before the module is assembled to the compressor, by bolting to an attachment flange fixedly attached to the turbine disk,

wherein said attachment flange defines a first plurality of orifices that receive a first plurality of bolts to fully preassemble said disk-shaped component to said turbine disk, and wherein said attachment flange further defines a second plurality of orifices radially equidistant with said first plurality of orifices, wherein said second plurality of orifices are free of bolts when said disk-shaped component is fully preassembled to said turbine disk and when the module is not assembled to the compressor; and

the compressor assembled to said module via a compressor flange, said compressor flange comprising drillings configured to receive a second plurality of bolts that pass through said second plurality of orifices in said attachment flange,

wherein said compressor flange is configured to receive heads of said first plurality of bolts so that said heads of said first plurality of bolts directly press against said disk-shaped component of said module without contacting said compressor flange,

wherein said compressor flange defines circular orifices having a diameter that is greater than said heads of said first plurality of bolts.

12. A gas engine according to claim 11 , wherein heads of said second plurality of bolts directly press against said compressor flange without contacting said disk-shaped component of said module.

13. A gas engine according to claim 12 , wherein each bolt of said first plurality of bolts is adjacent and between two consecutive bolts of said second plurality of bolts.

14. A gas engine according to claim 13 , wherein said first plurality of bolts includes four bolts and said second plurality of bolts includes twenty-eight bolts.

15. A gas engine according to claim 13 , wherein said first plurality of bolts plus said second plurality of bolts total no more than twenty-eight bolts.