To provide a high-speed rotating engine capable of particularly preventing a wear of a rotating part thereof, wherein a turbine for circulating a gas through a thermal cooling cell, is droven.

The hardening cell, wherein parts of steel are hardened by circulating the gas through a surrounding wall 23 sealed, has at least one static aspirator (Venturi nozzle) 26 for circulating the gas, and is controlled for a gas pressure in a gas inlet of this static aspirator to be larger than an atmospheric pressure. Preferably, a fluid of an inductor is injected into the static aspirator under the pressure of 20 to 80 bar.