Question 685Steam Plants - Assistant Engineer

The correct answer is C) operate the lube oil purifier on the main lube oil sump. Preheating the main turbine lube oil prior to rolling over the main unit is an important step to ensure proper lubrication and prevent damage to the turbine. Operating the lube oil purifier on the main lube oil sump is a common method to achieve this preheating. The purifier will circulate and heat the lube oil, bringing it up to the proper temperature before starting the main unit. The other options are incorrect because: A) bypassing the lube oil gravity tank would not effectively preheat the oil, B) running both lube oil pumps simultaneously would not heat the oil, and D) increasing gland sealing steam pressure is not directly related to preheating the lube oil.