Various Types Of Angle Seat Valves

An angle seat valve can be classified by actuator action, valve position, body design, and flow arrangement. Common types include normally closed, normally open, single-acting, double-acting, standard angle-seat, and Y-type designs. Each type has a different operating method or internal configuration.

Main Types of Angle Seat Valves

A seat valve uses a movable sealing element that presses against a fixed seat. In an angle-body design, the inlet and outlet are arranged at approximately 90 degrees.

The main types include:

1. Normally Closed (NC): Closes when control air is removed.
2. Normally Open (NO): Opens when control air is removed.
3. Single-Acting: Uses air for one movement and a spring for return.
4. Double-Acting: Uses air for both opening and closing.
5. Standard Angle Seat: Uses the conventional angled body.
6. Y-Type: Uses a Y-shaped body and flow passage.

Normally Closed Angle Seat Valve

A normally closed angle seat valve stays closed without pneumatic pressure. Control air moves the actuator and opens the valve.

This configuration is one of the common pneumatic arrangements for automatic flow shutoff.

Normally Open Angle Seat Valve

A normally open angle seat valve remains open when the actuator receives no control air. Pneumatic pressure moves the valve toward the closed position.

This configuration provides the opposite operating state to the normally closed type.

Single-Acting Type

A single-acting pneumatic angle seat valve uses compressed air for one stroke and a spring for the return stroke.

It can be divided into two basic forms:

• Normally Closed: Air pressure opens the valve.
• Normally Open: Air pressure closes the valve.

Double-Acting Angle Seat Valve

A double-acting design uses compressed air for both valve movements. Opening and closing are controlled through separate pneumatic signals.

The main classification features are:

1. No spring return for the operating stroke.
2. Air pressure controls opening.
3. Air pressure controls closing.
4. Both valve positions are actively controlled.

Y-Type Angle Valve

A y type angle valve has a Y-style body rather than the conventional angle-seat body. Its flow passage follows a different internal geometry.

This type is commonly separated from standard angle-seat construction because its body and flow arrangement are different.

Manual and Pneumatic Types

Angle seat valves can also be classified according to their operating method:

• Manual type: Operated directly through a handwheel or handle.
• Pneumatic type: Operated through compressed air.
• Single-acting pneumatic: Uses air and spring force.
• Double-acting pneumatic: Uses air for both directions.

A pneumatic angle seat valve is therefore a subtype defined by its actuation method rather than by a different sealing principle.

Type Classification at a Glance

The main types of angle seat valve are distinguished by operating action, actuator arrangement, and body configuration. These classifications describe the different forms of the same basic valve principle without changing its fundamental sealing mechanism.