🔍 Key Concepts

• Cross-compounded turbine plant layout (what ‘cross-compounded’ means in terms of separate shafts/units) • Normal steam flow path in marine turbine plants (from boiler to HP to LP to condenser) • Difference between simultaneous admission to multiple casings vs. staged expansion (HP then LP)

💭 Think About

• Think about how steam energy is most efficiently used: does it usually expand in stages (high to low pressure) or all at once in several casings? • In a cross-compounded plant, how many turbine shafts are there, and which pressure stages are on each shaft? • Would it make thermodynamic sense for high-pressure steam to go directly to the condenser without passing through low‑pressure expansion first?

✅ Before You Answer

• Verify how ‘cross‑compounded’ differs from ‘single‑reduction’ or ‘single‑flow’ turbines in layout, not in basic steam flow direction. • Confirm the usual order of expansion of steam in a marine propulsion turbine: boiler → ?‑pressure turbine(s) → ?‑pressure turbine(s) → condenser. • Eliminate any option where steam bypasses a lower‑pressure turbine and goes straight to the condenser while still at relatively high energy.