Types of control valve:
1. Based on number of plugs: Control valves can be classified as single seated valve and double seated valve
2. Based on action: Control valves operated through pneumatic actuators can be either air to open or air to close
3. Based on flow characteristics : Control valves can be classified as quick opening valve, linear opening valve , equal percentage valve
4. Based on construction
1. Angle Valve
2. Globe valve
3. Diaphragm Valve
4. Butterfly valve
5. Rotary valve
6. Ball valve
7. Sliding cylinder valve