characterised by having a single rotor operable in either direction of rotation, e.g. by reversing of blades (combinations of machines or engines F01D13/00)

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Non-positive-displacement machines or engines, e.g. steam turbines (wit working-fluid flows in opposite axial directions for balancing axial thrust F01D3/02; with other than pure rotation F01D23/00; turbines characterised by their use in special steam systems, cycles, or processes, regulating devices therefor F01K) > characterised by having a single rotor operable in either direction of rotation, e.g. by reversing of blades (combinations of machines or engines F01D13/00)