Sequence control valve dedicated to controlling the operation sequence of multiple actuators and cylinders in pneumatic systems. Used in manufacturing line automation equipment to operate pneumatic devices step by step according to process sequences. Includes timer-equipped sequence valves, step sequence valves, and programmable sequence valves, essential for continuous operation control of assembly lines, conveyor systems, and press machinery. Distinguished from simple ON/OFF control valves and flow control valves by having time-series control functions. Enables automation of complex manufacturing processes when combined with PLC control.