Which type of valve is shown as #7 on the iso?

• A. Globe valve
• B. Ball valve
• C. Control valve
• D. Check valve

Answer: (C)

In ISO hydraulic-fluid power symbols, a valve that is meant to be adjusted by a control signal is shown with an actuator attached to the valve body. That actuation element (electric, pneumatic, or hydraulic) indicates modulation of the valve opening to regulate flow or pressure, not just a simple on/off function. The symbol for a control valve includes this actuator indication, setting it apart from passive valves.

So the symbol in this position identifies a valve that is operated by a control input, which is why it’s the control valve. The other valve types—globe, ball, and check—are typically drawn without an attached actuator and represent more basic directional or one-way functions, not regulated flow.