🔍 Key Concepts

• Flow direction control in piping systems • How non-return / one-way devices work in fluid systems • Typical role of safety/relief valves versus flow-control devices

💭 Think About

• Which component is specifically designed to allow flow in only one direction and stop it from going back the other way? • In an auxiliary exhaust line, if the deaerating feed tank floods, what kind of device would stop that water from backing into the exhaust? • Which option is meant for pressure protection rather than for stopping reverse flow?

✅ Before You Answer

• Identify which choice is a one-way / non-return device in piping • Separate components that move fluid (like pumps) from those that control direction of flow • Confirm which valve type is normally used to relieve excess pressure rather than prevent backflow