Valves with NAMUR-Interface - Lever actuated valves | Hafner

Hafner NAMUR Lever-Operated Air Valves

The Hafner HVN / HVRN series are manually actuated pneumatic valves with NAMUR [1/4”] interface, designed for direct mounting on rotary pneumatic actuators used in process valve automation. These valves are specified where local manual operation of the actuator is required, without solenoid or pilot signal from a remote control circuit.

Available Functions

• HVN 311 701: 3/2 single solenoid, NC, spring return. Used with single-acting actuators with spring return.
• HVRN 320 701: 3/2 double solenoid, lever latches in both positions. Suitable where manual command must remain engaged.
• HVN 511 701: 5/2 single solenoid, spring return. For double-acting actuators with defined fail position when lever is released.
• HVRN 520 701: 5/2 double solenoid, maintains selected position until manually switched.

Technical Specifications

All models feature G 1/4” ports, flow rate 1250 l/min, operating pressure 1–10 bar, actuation force 20 N, and NAMUR [1/4”] mounting interface. Suitable for filtered, lubricated or non-lubricated compressed air.

Selection Criteria

Valve selection is based on:

• Single-acting or double-acting actuator type
• Required process valve fail-safe position
• Monostable or bistable lever operation
• 3/2 or 5/2 pneumatic logic
• Available instrument air pressure
• Required actuator open/close time

Applications

Used for manual local control of butterfly valves, ball valves, dampers, and process actuators. Typical in commissioning, bypass operations, manual line isolation, and installations without electrical actuation at the point of use.

Maintenance

Routine checks include NAMUR O-rings, actuator mounting integrity, exhaust leakage, air quality, lever mechanism wear, and correct spring return (HVN types). For HVRN variants, verify stable mechanical retention in both positions.