Flange Ball Valve

What is a Flanged Ball Valve?

As the name suggests, a flanged ball valve is a type of valve that combines a "ball" as its closure element and "flanges" as its connection method.

The Ball Core:

Inside the valve, there is a ball with a through-hole. When the axis of this through-hole aligns with the pipeline axis, media flows through completely, and the valve is in the open state. Rotating the ball 90 degrees blocks the hole, putting the valve in the closed state.

Flanged Connection:

The valve body has flanges at both ends. These are securely fastened via bolts to matching flanges on the pipeline. This connection method is very robust, suitable for medium/high-pressure and large-diameter pipelines, and facilitates easy installation and removal.

II. Main Structural Components

Valve Body: The main housing that contains all internal components, with flanges at both ends.

Ball: The core closure element, typically a hollow sphere with a bore. Its surface is often hardened or lined with engineering plastics (e.g., PTFE) to ensure sealing.

Stem:

Connects the handle/actuator to the ball, transmitting torque. Usually features a blow-out-proof design.

Valve Seat (Seal Ring):

Located between the ball and the valve body, it creates the seal. Common materials include PTFE (Teflon), PPL (Para Poly Phenyl), metal, etc.

Stem Packing (Gland):

Located where the stem extends from the body, it prevents media leakage along the stem by compressing packing material (e.g., graphite).

Actuator:

Can be a manual lever/handwheel, or a pneumatic, electric, or hydraulic actuator for remote or automatic control.

III. Working Principle

Its working principle is very simple and direct, similar to a household water tap:

Opening:

Operate the handle or actuator, which rotates the stem 90°, aligning the ball's bore with the pipeline, allowing media flow.

Closing:

Reverse the operation; the stem rotates another 90°, positioning the ball's bore perpendicular to the pipeline. The ball blocks the flow path, and the seat seals tightly against the ball, cutting off the media.

IV. Core Features and Advantages

· Minimal Flow Resistance:The bore diameter of a full-port ball valve is essentially equal to the pipeline's inner diameter, allowing media to pass through almost unimpeded with very low pressure drop.

· Quick Operation:Only a 90° rotation is required to fully open or close, enabling fast operation.

· Excellent Sealing:Advanced seat materials and designs (e.g., elastic seats) enable bidirectional sealing and maintain low leakage over long-term use.

· Long Service Life:The ball and seat seals are resistant to scoring and wear very slowly under normal operating conditions.

· Easy Maintenance:Most employ a modular design, especially three-piece ball valves, making on-line disassembly and seat replacement straightforward.

· Wide Application Range:From small to ultra-large diameters, from vacuum to high pressure, from cryogenic to high temperatures. By selecting different materials (e.g., carbon steel, stainless steel, alloys, plastics) and seals, they are suitable for various media including water, steam, oil, gas, and corrosive fluids.