SMC Rotary Knob Pressure Release Valve VHS20-D Series, G 1/4 in, III B

This pressure release valve is a Compact pneumatic safety device designed to control and isolate compressed-air supply in industrial automation systems. It provides a manual means to switch supply and exhaust paths, offers a visible supply/exhaust indicator and can be padlocked in the exhaust position to prevent accidental pressurisation while maintenance is carried out. The unit is intended for mounting on modular FRL assemblies and similar pneumatic manifolds.

• Polybutylene terephthalate body reduces weight and resists heat
• Rotary knob with red control button enables positive manual operation
• Three ports with G-threading allow standard pneumatic connections
• 14 098 L/min maximum flow supports high-volume Air systems
• Operates across −5°C to +60°C for broad plant environments
• Maximum operating pressure 10 bar for robust system isolation

• Suitable for isolating supply on automated assembly lines
• Ideal for lockout during maintenance of pneumatic actuators
• used with modular FRL units in control panels
• Can be used for emergency pressure release on test benches
• Suitable for integration into machine safety circuits requiring padlockability

The valve functions correctly from −5°C up to +60°C without freezing or heat-related performance loss.

The exhaust port uses G-threading and the unit supports G thread on the three-port configuration for standard pneumatic fittings.

The control uses a push-and-turn two-step action with locking holes so it must be pushed before rotated, and a padlock can secure it in the exhaust position.

The device achieves a maximum flow of 14 098 L/min enabling reduced pressure drop in high-flow pneumatic circuits.