Pneumatically Actuated Valves - Logic elements | Hafner

Pneumatic Logic Elements – Hafner

Hafner pneumatic logic elements are used for implementing logic functions in automation circuits without electrical signals at the control point. Typical applications include sequence control, interlocks, reset circuits, signal selection, and two-condition confirmation prior to valve or cylinder actuation. These components are suitable for compressed air and inert gases in industrial automation environments.

OR and AND Pneumatic Logic Gates

• VA 341 / VA 401 – OR-gate: Output is actuated when pressure is present at either input. Available with Ø4 or G 1/8” connections. Flow rate: 280 l/min. Operating pressure: 1–10 bar. Suitable for standard pneumatic circuits requiring signal selection or redundancy.
• ES 341 / ES 401 – AND-gate: Output is actuated only when both pneumatic signals are present simultaneously. Same flow and pressure ratings as OR-gate. Used for safety interlocks and dual-signal confirmation.

Manifold Mounting Versions

For sub-base installation, VA 304 (OR) and ES 304 (AND) are available with orifice 3 mm, 280 l/min flow, and 1–10 bar pressure range. The RP 2 344 manifold base is used for VA 304 and ES 304 with Ø4 tube connection. These variants facilitate modular assembly and maintenance in panel-mounted systems.

Pilot-Operated Valves for Sub-Base Mounting

This category includes pilot-operated valves for manifold mounting:

• P 310 304: 3/2 NC, air-spring return, 280 l/min, 2–10 bar.
• P 311 304: 3/2 NC/NO, mechanical spring, pilot pressure 3–10 bar.
• P 320 304: 3/2 double pilot, pilot pressure 2.5–10 bar.
• P 322 304: 3/2 double pilot with priority at port 12.
• P 510 / 511 / 520 / 522 304: 5/2 functions for double-acting cylinders, with RP 5 344 base.

Selection Criteria

Selection is based on logic function, required flow, available signal pressure, memory requirements, and sub-base type. For safety-related sequences, ensure complete venting of pilot lines to prevent trapped pressure that could alter circuit logic. All components are compatible with standard industrial compressed air per ISO 8573-1. Sealing materials and actuator options are available for specific media and operational requirements.