🔍 Key Concepts

• Pressure sensing element vs. control element in a hydraulic regulator • How a bellows responds to pressure changes compared to solid parts like rods or blocks • The function of a pilot valve in a hydraulic system (controls flow/pressure, but is it the sensor?)

💭 Think About

• Look at the labeled part that is directly exposed to gland seal pressure—what component actually moves first when pressure changes? • Which of the listed choices is designed to flex or expand/contract with pressure, rather than simply transmit motion or route flow? • Trace the motion: when pressure at the gland changes, which part of the drawing would deform or shift to signal that change to the linkage above?

✅ Before You Answer

• Identify which part of the illustration is in direct contact with the gland seal pressure and note its shape and construction. • Ask whether each choice (A–D) is normally used as a sensor or as a mechanical linkage/flow control device in hydraulic governors. • Eliminate any components that are clearly just structural supports or connection points (not pressure-sensitive elements).