🔍 Key Concepts

• Purpose of lube oil systems in steam/turbo generators • How nozzle lifting beams and power pistons control steam admission to the turbine • What functions are mechanical/hydraulic vs. electrical in an automated plant start sequence

💭 Think About

• Ask yourself: Before any moving parts operate, what is the FIRST protection the machinery needs—mechanical support, control action, or electrical trip setup? • Consider which of the listed actions would plausibly depend on HYDRAULIC (oil) pressure instead of steam pressure or electrical signals. • Think about the normal direction of movement for a nozzle lifting beam at startup: do we usually want to admit steam or keep it shut while checks are completed?

✅ Before You Answer

• Verify which components in a turbo generator are actually operated by lube oil pressure (bearings, servomotors, power pistons). • Check which listed functions are typically handled by steam pressure rather than lube oil (such as lifting or loading valves/nozzles). • Confirm that the purpose of external lube oil before rolling is primarily to protect and position mechanical parts, not to directly trigger electrical trips.