fastening section application_number US 201013256826 A description fig1 shows an axial fan wheel hub 1 in perspective view axial fan wheel hub 1 essentially corresponds to a hub according to prior art it has a central bore 2 for connecting u2014 if necessary by using a hub core that is not shown u2014 with a ventilator spindle that is not shown around central bore 2 fastening bores 3 are situated on a circular line for establishing a flange connection with the hub core u2014 not shown u2014 for fastening with a ventilator spindle that is not shown beyond that axial fan wheel hub 1 has a cylindrical fastening section 4 fastening section 4 has an inner casing surface 5 in cylindrical fastening section 4 radial adapter bores 6 are present at equal angular distance in the schematic illustration according to fig1 not all adapter bores 6 that are actually required for load free operation of a ventilator are shown adapter bores 6 serve to accommodate ventilator blades that are not shown with the aid of blade pins that are attached to the ends of the ventilator blades in prior art fastening of the ventilator blades is accomplished by inserting the blade pins into the radial adapter bores 6 in cylindrical fastening section 4 of axial fan wheel hub 1 and subsequently screwing together the ventilator pin having a thread with the aid of a screw nut located at inner casing surface 5 a tapered casing section 11 is attached to cylindrical fastening section 4 having radial adapter bores 6 to the extent axial fan wheel hub 1 is made of aluminum this arrangement has however insufficient tensile strength at temperatures as they can occur in tunnel fires i e at 300 u00b0 c to 400 u00b0 c with the help.