A sequence valve in hydraulic circuits is used to

A sequence valve in hydraulic circuits is used to

• A. Regulate flow by time
• B. Hold back flow until a set pressure is reached
• C. Divert flow to tank
• D. Limit maximum flow

Answer: (B)

A sequence valve ensures that one part of a hydraulic system must reach a certain pressure before the next part can move. It sits in the line to a downstream circuit and stays closed, holding back flow, until the upstream pressure climbs to the preset level. Once that set pressure is reached, the valve opens and flow is allowed to continue to the next stage, causing the second actuator or circuit to operate. This creates a controlled order of operations—one action completes or reaches a defined pressure before the next begins. This is different from simply regulating flow over time (which would rely on a timer) or diverting flow to a tank (a drain or relief path), or limiting maximum flow (that’s the job of a flow-control device). The key idea is using a pressure threshold to sequence actions in the correct order.

A sequence valve ensures that one part of a hydraulic system must reach a certain pressure before the next part can move. It sits in the line to a downstream circuit and stays closed, holding back flow, until the upstream pressure climbs to the preset level. Once that set pressure is reached, the valve opens and flow is allowed to continue to the next stage, causing the second actuator or circuit to operate. This creates a controlled order of operations—one action completes or reaches a defined pressure before the next begins.

This is different from simply regulating flow over time (which would rely on a timer) or diverting flow to a tank (a drain or relief path), or limiting maximum flow (that’s the job of a flow-control device). The key idea is using a pressure threshold to sequence actions in the correct order.