Flange Style Double offset Butterfly Valve-Metal Seat

1. Introduction

The double eccentric butterfly valve belongs to the family of the offset butterfly valves. This valve has two stems offset from the center:

• The axis of the shaft is behind the centerline of the sealing point of the disc to the seat.
• The axis of the shaft is eccentric to the center of the valve/pipeline.

This design creates a cam action during operation to lift the seat out of the seal and reduce the friction during the first 10 degrees of opening and final 10 degrees of closing. Thus, compared with the zero offset butterfly valve, this double offset butterfly valve offers longer life by reducing contact between valve, discs, and seats. For this reason, the double eccentric butterfly valve is ideal for operations that involve high pressures and particulate fluids.

For these applications, the flange connection and lug connection are more suitable as they offer a more firm and steady connection for high-pressure applications.

In terms of the types of the seat design, there are Metal Seated Offset Butterfly Valve and Soft Seated Offset Butterfly Valve: compared with rubber lined butterfly valve, the metal seat double offset butterfly valve withstands a higher temperature and pressure.

2. Specifications

3. Applications

As we mentioned before, this Flange Style Double Offset Butterfly Valve is a high-performance butterfly valve, which is suited for high-pressure applications, such as liquids and gasses in oil and gas processing, power, marine, chemical, and petrochemical industry, etc.

In summary, the main applications are the followings:

Water distribution

Water treatment

Wastewater

Dams

Power plants

Industry

4. Advantages of our products

Our Metal Seated Double Offset Butterfly Valve with Flange is featured by the following advantages:

a. Tight sealing: The balance of this valve is in the stem placed behind the circular disc. It allows the disc to self-adjust to the center, ensuring tight sealing.

b. Longer service life: Even when the valve is fully opened, the valve does not touch the soft seat, ensuring a longer service life. Compared with the soft seat, the metal seat withstands higher liquid pressure and temperature and is highly corrosion-resistant. Thus this Metal Seated Double Eccentric Butterfly Valve offers a longer service life.

c. Wide range of sizes: we offer a wide range of sizes for this high-performance butterfly valve: in terms of its diameter, from the 200mm type to the 1600mm type.