the case in this case the description will apply to a particular stage 6 of fixed blades in which the setting of the blades 7 is variable and pivots 8 passing through the stator 1 and that are connected to it by bearings 9 the main ducts of the blades 7 pass through the pivots 8 a circular header pipe 10 draws in air sucked in at the outside face of the stator 1 through connections 11 that are connected to the ends of the main ducts 3 respectively on the end portions of the pivots 8 fig2 shows the layout at this location the pivots 8 are provided with connection portions 12 usually with a square section outside the stator 1 control rods 13 controlling the setting of the blades 7 that are only shown roughly and threaded parts 14 on which nuts 46 are engaged retaining the pivots 8 preventing them from sliding in their bearings 9 rotation retainers not shown here hold the nuts 46 at fixed positions on the threaded portions 14 according to the invention the pivots 8 are prolonged towards the outside of the end portions 15 that make a junction with the connections 11 in this embodiment these connections are flexible pipes for which the connection ends each carry a ring 16.