Distinction of flow control valve and sequence valve.
1. Flow Control Valve
Cylinder A moves slowly during cylinder B moves fast.
Gage shows approx. 5kgf/㎠ when cylinder B contact with workpiece.
In other words, cylinder B waits until cylinder A approaches due to equal pressure of circuit.
2. Sequence Valve
Cylinder C has no hydraulic pressure during cylinder D moves fast.
When set pressure of sequence valve is reached, cylinder C moves as hydraulic is provided.
Cylinder D’s clamping force is already very high.