The adjustable spherically seated self-aligning bearing housings used in main turbines are provided with oil deflector rings. The function of these rings is to __________.

Correct Answer: Option D — prevent the external leakage of oil out of the bearing housing

Oil deflector rings fitted outboard of turbine bearing housings act as physical barriers and slinger devices to prevent lubricating oil from escaping externally along the shaft and contaminating the machinery space.