What is a Sequence Valve?

A sequence valve is a pressure-operated valve that diverts flow to a secondary circuit when pressure in the primary circuit reaches a set level. This ensures actuators operate in a specific order without additional controls.

How Sequencing Works

1. Primary actuator receives flow first
2. When primary builds pressure (hits end of stroke or load), pressure rises
3. Sequence valve opens at set pressure, allowing flow to secondary
4. Secondary actuator operates

Setting Calculation

The sequence valve setting must be higher than the primary circuit operating pressure but lower than system relief:

P_sequence = P_primary_max x Safety Factor

Typically 10-20% margin above maximum primary pressure.

Common Applications

• Clamp-then-work: Clamp closes, builds pressure, work cylinder extends
• Lift-then-tilt: Lift platform, then tilt load
• Press operations: Position, then press, then eject

Key Considerations

• Allow sufficient pressure margin between stages (min 15-20 bar)
• Account for pressure spikes during acceleration
• External drain required for some designs