🔍 Key Concepts

• Thermal expansion of turbine casings and rotors in large main propulsion turbines • How reactions, thrust, and casing forces are transmitted to the ship’s hull or foundation • Purpose of a flexible I‑beam or flexible support at one end of large machinery

💭 Think About

• Think about which part of a main turbine gets hottest and how that might change its length during operation. What must the mounting system allow for? • Consider what kind of forces a turbine produces in normal operation: torque, thrust, thermal growth. Which of these would a specially designed flexible beam primarily be dealing with? • Ask yourself: if the forward end is rigidly mounted but the beam itself is flexible, what motion or force is that design trying to control or accommodate?

✅ Before You Answer

• Verify which turbine component(s) need freedom to expand/contract along their length without creating harmful stress. • Check which option refers specifically to the light or low‑temperature end versus the hotter, loaded sections of the turbine. • Consider which choice best matches the idea of a support that is flexible in one direction (for movement) but still rigid enough to carry load.