DEVICE FOR SHAFT COOLING OF FREE TURBINE OF GAS TURBINE UNIT Russian patent published in 2016 - IPC F01D5/08 

FIELD: machine building.

SUBSTANCE: device for shaft cooling of free turbine of gas turbine unit includes turbine with shaft, and guide vanes. In the casing between the guide vanes and first bearing two diametrically located holes with air ducts are made. Cold air via one of the air ducts is delivered to the turbine shaft, and via the another air duct the air heated by shaft is exhausted. In area of holes with air ducts the shaft has transverse holes not passing through the centre of rotation of the shaft, the transverse holes are located at different transverse cross-sections of the shaft and have similar angular displacement. The transverse holes are made with possibility of the cold air entrapping during the shaft rotation, and its passage through the shaft body this cooling the shaft. In the area of air supply the shaft has increased shaft diameter, its cross-section area is larger by value of area of the longitudinal cross-section of the transverse hole in this section.

EFFECT: invention simplifies cooling device for shaft of free turbine.

2 dwg