🔍 Key Concepts

• Meaning of design pressure in boiler construction and safety calculations • Difference between design pressure and operating pressure (normal and overload) • Role of the manufacturer’s specified pressure used for material selection, drum thickness, and safety valve sizing

💭 Think About

• Ask yourself: At what pressure do engineers choose materials, wall thickness, and safety devices for the boiler—normal operating, overload, or a specified maximum? • Consider whether design pressure must be higher, lower, or the same as everyday operating pressure to ensure a margin of safety. • Which option describes a condition that would be used on drawings, nameplates, and in classification/approval documents, rather than just day‑to‑day running conditions?

✅ Before You Answer

• Verify which choice clearly refers to a specified maximum pressure used for design calculations, not just how the boiler is normally run. • Check whether design pressure should reasonably be greater than or equal to the normal operating pressure to allow a safety margin. • Eliminate any option that ties design pressure only to overload or abnormal operation, instead of a defined design value.