Question 39 QMED03 - Oiler

The Correct Answer is A. **Explanation for Option A (the hand-operated or auxiliary lube oil pump):** When starting a turbogenerator, the main turbine shaft is stationary or rotating very slowly. The **main lube oil pump (MLOP)** is typically driven directly by the main turbine shaft (either mechanically or sometimes electrically, but tied to the turbine's speed). Since the turbine is not yet running at sufficient speed, the MLOP cannot provide the necessary oil pressure. Therefore, an independent, electrically-driven pump—referred to as the **auxiliary lube oil pump (ALOP)** or sometimes the "hand-operated" (in older terminology reflecting manual activation) or "startup" pump—is used. This pump is energized automatically or manually to ensure that adequate lubrication pressure is maintained across the bearings before the turbine reaches a speed where the MLOP can take over. **Why Other Options Are Incorrect:** * **B) the main lube oil pump:** The main lube oil pump is driven by the main turbine shaft (or geared to it). During startup, the turbine speed is too low (or zero) for the main pump to generate adequate pressure. * **C) a line from the other generator:** While systems might share common oil reservoirs, taking pressure directly from another operating generator's lube oil discharge line would be complex, inefficient, and highly unreliable for maintaining the critical pressure required for the unit being started. Each unit must have its own reliable, dedicated means of startup lubrication. * **D) a line from the gravity tank:** The gravity tank (or overhead emergency oil tank) is an **emergency** system designed to provide lube oil for coast-down lubrication *after* a complete pump failure or unit trip, preventing bearing damage as the turbine slows to a stop. It uses gravity, which provides minimal pressure, and is not designed to provide the required flow and pressure for an active startup procedure.