🔍 Key Concepts

• Compare how a huddling chamber looks versus a simple nozzle-type safety valve in cross‑section diagrams. • Notice whether the design uses escaping steam to create additional lifting force on the disc by increasing the effective area. • Look closely at the lower body: is there an annular chamber or ring around the nozzle where steam can collect and redirect flow?

💭 Think About

• Which of these valve types relies on building up pressure and flow in a small side chamber around the disc to produce a quick, ‘pop’ opening? • In the illustration, does the escaping steam simply go straight up from the seat, or does it first enter a shaped side space that would increase the upward force on the disc? • How would a jet‑flow or nozzle‑reaction design look different in terms of the direction and confinement of the discharge steam?

✅ Before You Answer

• Identify any annular chamber or blowdown ring around the nozzle and consider which option uses that feature. • Check whether the spring is the only lifting force, or if the geometry creates extra lift from redirected steam pressure. • Before choosing, mentally rule out designs that do not use a side chamber or ring to generate a ‘pop’ action.