Double Eccentric Butterfly Valves

The Double Eccentric Butterfly Valve is an advanced type of valve designed to control the flow of fluids in various industrial applications. It features a unique design with two eccentricities in its construction, ensuring a tight seal and reduced wear during operation. This valve type is known for its ability to provide excellent flow control with minimal torque requirements, making it ideal for applications involving high flow rates and challenging conditions. The double eccentricity also helps minimize seat wear and enhances its lifespan, ensuring reliable performance over time.

A Double Eccentric Butterfly Valve is engineered for precision and efficiency in regulating fluid flow. Unlike traditional butterfly valves, this design incorporates two offset axes, which reduces friction between the valve’s seal and the seat during operation. The result is a smoother opening and closing motion, lower pressure drops, and improved durability. Commonly used in industries such as water treatment, oil, and gas, the double eccentric design allows for a robust solution where performance, longevity, and ease of maintenance are essential.

Material List (High Performance Fire-safe Butterfly Valve)

No.	Part Name	Materials	Optional Materials
1	Body	Cast Steel	SS, Monel
2	Spacer	SS	SS, Monel
3	Bushing	PTFE+Bronze	Lubricated Bronze
4	Disc	Cast Steel	SS
5	Gasket	Graphite	Graphite
6	Seal Ring	PTFE+PTFE+SS	SS+Graphite
6a	Seat	Carbon Steel+1Cr	SS, Monel
6b	Gasket	Graphite	Graphite
6c	Seal Ring	SS	—
6d	Gasket	Graphite	Graphite
7	Gasket	Graphite	Graphite
8	Metal seat tongue	SS	—
9	Gasket	Graphite	Graphite
10	Retainer	NBR	FPM
11	Retainer Flange	Carbon Steel	SS, Monel
12	Screw	SS	316, Monel
13	Bushing	PTFE+Bronze	Lubricated Bronze
14	Packing Seat	SS	SS, Monel
15	Packing	Graphite	PTFE
16	Retainer	Carbon Steel	SS
17	Packing Bushing	SS	SS
18	Yoke	Carbon Steel	—
19	Limit Disc	Carbon Steel	SS
21	Lever	Carbon Steel	—

Sealing Structure of Double Eccentric Seal Butterfly Valve

Principal of Seat Sealing

Disc closed, medium enters from the upstream of seat. Under the force of medium, sealing ring will get close to the sealing face of disc, and the elasticity and deformation of sealing ring will function to guarantee the sealing performance.
Disc closed, medium enters from the downstream of seat. Under the extrusion of press board ring. sealing will overcome the acting force of medium and get close to the sealing face of disc. thus to guarantee the sealing performance.

Key Features

Double offset disc minimizes seat wear
Bi-directional sealing performance
Low operational torque and long cycle life
Compact, lightweight construction
Suitable for both on/off and throttling service
Available in Wafer, Flanged, Welded & Expansion types

Applications

Oil & Gas pipelines
Chemical processing
Power plants & utilities
Water distribution & desalination
HVAC systems
Industrial flow systems

Product Range

1. Double Eccentric Wafer Butterfly Valve

This wafer-style valve is designed for compact installations and offers reliable bi-directional sealing with reduced seat wear. Its double eccentric design ensures minimal contact between the disc and seat, lowering operational torque and extending service life. Ideal for industrial systems where space is limited and high performance is essential.

2. Double Eccentric Welding Butterfly Valve

Engineered for permanent, high-integrity connections, this valve features welded ends that eliminate flange-related leak points. The double offset geometry reduces friction during opening/closing, enabling smoother operation and longer seat durability. Perfect for high-pressure applications in oil & gas, petrochemical, and steam lines.

3. Dual Eccentric Flange Type Cast Structure Butterfly Valve

This heavy-duty cast valve with flanged ends provides high structural strength and resistance to deformation under pressure. The dual eccentric disc design minimizes seat contact, reducing wear and enhancing sealing performance. Suitable for harsh operating environments such as chemical processing and power plants. Perfect for high-pressure applications in oil & gas, petrochemical, and steam lines.

4. Expansion Butterfly Valve

Designed to absorb pipeline expansion, vibration, and misalignment, the expansion-type valve ensures system stability and leak-free operation. It combines the flexibility of movement with reliable shutoff and is widely used in HVAC, water supply, and infrastructure systems requiring dynamic adjustment capabilities.

5. Double Eccentric Flange Butterfly Valve

A standard flanged version with double offset construction, this valve provides excellent throttling and shut-off capabilities. The offset disc reduces seat stress and improves longevity, making it ideal for water treatment plants, process industries, and power stations requiring precise flow control and easy maintenance access.

Double Eccentric Butterfly Valves