Question 344Steam Plants - 1st Asst/Chief70% to pass
To prevent damage to the turning gear mechanism, which of the following procedures must be carried out before the turning gear is engaged?
AI Explanation
The correct answer is A) The propeller shaft must be stopped and held stationary until the clutch is engaged.
This is the correct procedure to prevent damage to the turning gear mechanism. The turning gear is used to slowly rotate the propeller shaft when the main engine is not running, in order to evenly distribute lubrication and prevent deformation of the shaft and other components. If the propeller shaft is not stopped and held stationary, engaging the turning gear while the shaft is still moving can cause significant damage to the turning gear mechanism.
The other answer choices are incorrect because they do not directly address the need to stop and hold the propeller shaft stationary. Putting the engine order telegraph on 'stop', setting the brake on the reduction worm shaft, or reducing the speed of the astern turbine do not necessarily mean the propeller shaft itself is stopped and held in place, which is the critical step to prevent turning gear damage.
Related Questions
#342 Which of the following statements is true concerning the coupling shown in the illustration? Illustration SE-0001 #343 Which of the devices listed is commonly used to compensate for the expansion and minor misalignments occurring between the main turbine rotor and the reduction gear? #345 In securing the main turbines, steam to the second stage air ejectors should be left on for a short period of time in order to _______________.#346 After properly lining up the main propulsion turbine for warm up, steam should first be admitted to the rotor through the _______________.#347 With vacuum up and the main propulsion turbine standing by while awaiting engine orders, it is necessary to roll the unit alternately ahead and astern every five minutes to _______________.