🔍 Key Concepts

• Definition of a pressure vessel under 46 CFR (closed container designed to hold fluids under pressure) • Difference between static containment of pressure (tanks, heaters, evaporators) and moving actuators in hydraulic systems • Typical marine boiler room and machinery space equipment that are classed and inspected as pressure vessels

💭 Think About

• For each option, ask: Is this a closed vessel primarily intended to contain a fluid under pressure, or is its main purpose something else? • Consider which items are normally subject to pressure-vessel code rules (like ASME) and which are treated more like machine components or actuators. • Think about whether the item stores significant volume of pressurized fluid, or simply transmits motion/force using fluid.

✅ Before You Answer

• Verify which item’s primary function is mechanical motion rather than storing fluid under pressure. • Check which of these are commonly found on boiler/pressure vessel nameplates in the engine room. • Confirm from 46 CFR that a pressure vessel is a closed container for holding gas or liquid at a pressure substantially different from ambient, not just any part that momentarily sees pressure.