時間：2025-04-02
The main differences between external pilot operated and internal pilot operated pneumatic solenoid valves lie in their working principles, usage scenarios, structural characteristics, and application scenarios
|Working principle | The working airflow of the external pilot solenoid valve is separated from the working airflow of the main valve body; The internal pilot operated solenoid valve operates under the same airflow|
|Application scenario | External pilot operated solenoid valve is suitable for situations where there is a large pressure difference between the inlet and outlet ports; Internal pilot operated solenoid valve is suitable for situations with small pressure differences|
|Structural characteristics | Internal pilot solenoid valve: compact structure, fast response speed, high control accuracy, low leakage risk, but limited installation and difficult cleaning; External pilot solenoid valve: easy to install, easy to clean, occupies a large space, has a slow response speed, and slightly lower control accuracy|
|Typical application scenarios|
External pilot type
-Vacuum system (such as suction cup control).
-In situations where the inlet pressure may be zero or fluctuating (such as pipelines after pressure relief).
-High reliability industrial automation equipment is required.
Internal pilot type
-Conventional pneumatic systems (such as cylinder driven, pressure stable pneumatic circuits).
-Simplified design when no external gas source is available.
-Low cost application requirements.
Selection suggestions
-Choose external pilot type: If the inlet pressure is insufficient, unstable, or requires zero pressure negative pressure to start.
-Choose internal pilot type: if the system pressure is stable and sufficient
In summary, both external pilot operated pneumatic solenoid valves and internal pilot operated pneumatic solenoid valves have their own advantages and disadvantages, and are suitable for different working conditions and requirements. Choosing the appropriate solenoid valve correctly is crucial for ensuring the stable operation of the system.
