The control valve consists of two main assemblies: valve body assembly and actuator assembly (or actuator system), which are divided into four series: single-seat series control valve, double-seat series control valve, sleeve series control valve And self-operated series control valve. Variations of the four types of valves can lead to many different applicable configurations, each with specific applications, features, advantages and disadvantages. While some control valves are used in a wider range of applications than others, control valves are not suitable for all applications to work together to create the best solution for enhanced performance and reduced cost.