Question 345Steam Plants - 1st Asst/Chief

The correct answer is D) dry out the main turbines. When securing the main turbines, leaving the steam to the second stage air ejectors on for a short period of time helps to dry out the main turbines. This is done to remove any accumulated moisture or condensation that may have built up in the turbines during maneuvering operations. Drying out the turbines is important to prevent potential damage or corrosion to the turbine components. The other answer choices are incorrect because they do not specifically address the need to dry out the turbines. Option A would not be the primary reason, option B is focused on bearing cooling rather than turbine drying, and option C is about removing non-condensable vapors, which is not the key purpose in this case.