Question 665Steam Plants - Assistant Engineer

The correct answer is A) provide reduction gear tooth inspection. The jacking gear on main propulsion turbines is used to slowly rotate the turbine shaft to allow for inspection of the reduction gear teeth without the turbine running. This enables maintenance personnel to visually inspect the condition of the reduction gear teeth, which is an important part of routine maintenance on marine propulsion systems. The other options are incorrect because the jacking gear is not used to provide propulsion in emergencies (B), reduce turbine speed during maneuvering (C), or lift the reduction gear casing (D). The primary purpose of the jacking gear is to facilitate inspection of the reduction gear, which is the correct answer (A).