Question 547Steam Plants - Assistant Engineer

The correct answer is C) rotor shaft and pinion shaft. On main turbine propulsion units, gear-type flexible couplings are generally used between the rotor shaft and the pinion shaft to allow for slight misalignment and absorb torsional vibrations. This helps ensure smooth power transmission from the turbine to the reduction gearbox. The other answer choices are incorrect because: A) The quill shaft connects the reduction gearbox to the propeller shaft, not the turbine. B) The second reduction and shaft thrust bearing are not connected by a flexible coupling. D) The rotor shaft and quill shaft are not directly coupled together with a flexible coupling.