Actuated on/off valve type 731 | AWS

Automatic On/Off Valve AWS Type 731

The AWS Type 731 is a pneumatically actuated 2/2 angle seat valve with a piston and external control. It closes against the flow direction and its default operation is NC, meaning normally closed without control air. This configuration is suitable for on/off isolation, not for proportional flow control.

Operating Range

• DN10–DN50.
• Operating pressure: 0 to 16 bar, depending on DN and actuator.
• Kv: 4.7 to 52.8 m³/h.
• Medium temperature: -10°C to +180°C.
• Ambient temperature: up to +60°C.
• Maximum viscosity: 600 mm²/s.
• Installation position: any.

Materials and Sealing

The body is made of stainless steel and the actuator from anodized aluminum. Seat sealing is available in PTFE or RTFE, with PTFE shaft sealing. Seat leakage is classified as Class A according to EN 12266-1.

Connections and Actuator Selection

Connections are internal thread G 3/8" to G 2". Welding ends according to DIN EN 10357, formerly DIN 11850, and DIN EN ISO 1127 / ISO 4200 are available upon request. Control air is 3–7 bar. For DN40, actuator selection is required: 80 mm for up to 8 bar or 100 mm for up to 16 bar. For DN50, the 100 mm actuator covers up to 9 bar.

Typical Applications

• Isolation of water, air, and neutral fluids,
• Auxiliary lines for machinery and skids,
• Filling, draining, and bypass,
• Automation with frequent open/close cycles.

Optional Features

Available with a 3/2 pilot valve for direct mounting, 6 mm tube connector, manual override, and electric position indicator.

FAQ

When to choose RTFE?
When enhanced PTFE is required for the seat without changing the basic temperature range.

What does NC mean?
In the event of control air loss, the valve returns to the closed position.