🔍 Key Concepts

• Set point vs. output pressure – which part of the device physically changes the force acting on the sensing element (diaphragm/spring)? • Spring compression adjustment – in pressure regulators and controllers, what component is usually turned to compress or relax a main spring? • Function of each labeled part (D, E, H, I) – use the illustration to match each part to what it actually does: locking, transmitting motion, or adjusting force.

💭 Think About

• Look at the top spring and diaphragm area: which labeled part is clearly designed to be turned with a wrench to change how tight the spring is? • Compare the lower nozzle/blade area (near F, G, H, I) with the upper adjustment area: which region is for fine nozzle/nozzle-disc alignment, and which is for changing overall operating pressure? • Ask yourself: if you wanted to permanently change the pressure at which the controller starts to move, would you adjust something on the nozzle tip, or the main loading spring that pushes on the diaphragm?

✅ Before You Answer

• Identify which labeled part directly changes compression of the main spring acting on the diaphragm when rotated. • Verify which part(s) are shown with a locknut or cap (often used to hold an adjustment after setting the desired set point). • Confirm that the action you choose would change the force balance on the diaphragm, not just the travel or clearance of the moving linkage.