Double Offset Butterfly Valve with Electric Actuator & Handwheel – Low Torque, Long Life

Product Overview

A double offset butterfly valve–also known as a double eccentric butterfly valve–represents a significant advancement over traditional concentric designs. In a concentric valve, the disc and seat remain in constant contact throughout the entire opening and closing cycle, causing continuous friction that leads to premature seat wear and high operating torque. The double offset design solves this problem by offsetting the stem axis in two directions–from both the disc centerline and the valve centerline–causing the disc to lift away from the seat immediately upon opening. After just a few degrees of rotation, the seal compression is fully released, eliminating sliding friction and delivering lower operating torque, extended seat life, and bubble-tight shut-off even after thousands of cycles.

This 10-inch model features a ductile iron body and disc (EN-GJS-400-15), a 304 stainless steel seat, an SS420 stem, and an electric actuator with worm gear and handwheel–finished in RAL 5015 epoxy coating. Available in sizes from DN100 to DN1800, this valve is ideal for water supply, wastewater treatment, power generation, and industrial applications. As an LRQA-certified ISO 9001:2015 OEM manufacturer with 19+ years of export experience, we offer fully customizable solutions–materials, sizes, pressure ratings, flange standards, coatings, and actuators–all tailored to your specifications.

Introduce:

Double Offset Butterfly Valve | DI Body & Disc| 304 Seat | SS420 Stem | EN 593

Tianjin Worlds Valve Co., Ltd.–Your Reliable Source for Durable, Cost-Effective Flow Control

EBF01-TF01 - Detailed Product Info

Technical Specifications

 

Key Features & Advantages

1. Double Offset Design–Less Friction, Longer Life

• Eliminates Sliding Friction–The double offset geometry causes the disc to lift away from the seat immediately upon opening, eliminating the continuous rubbing that wears out concentric valves. This means significantly longer seat and disc life.

• Lower Operating Torque–With friction eliminated after just a few degrees of rotation, the valve requires substantially less torque to operate. This allows for smaller, more economical actuators and smoother manual operation.

• Bubble-Tight Shut-Off–The double offset design ensures the disc seats firmly against the 304 stainless steel seat when closed, delivering zero-leakage sealing certified to API 598–even after thousands of cycles.

 

2. Double Flanged Connection–Maximum Rigidity

• Integral Flanges on Both Ends–The valve bolts directly to mating pipe flanges on both sides, providing the most secure and rigid connection available–ideal for large-diameter and high-flow systems.

• Bidirectional Dead-End Service–Supports isolation and removal of pipe sections on either side while the valve remains closed and sealed.

• Easier Alignment–Integral flanges simplify mounting and centering between pipeline flanges–no complicated alignment procedures.

 

3. Body & Disc Material–Ductile Iron EN-GJS-400-15 (GGG40)

• High Strength–Offers tensile strength of ≥400 MPa and yield strength of ≥250 MPa, providing reliable performance under pressure surges.

• Excellent Elongation–Minimum 15% elongation ensures the material can withstand thermal expansion and pipeline stress without cracking.

• Impact Resistance–The nodular graphite structure provides exceptional toughness, withstanding mechanical shock and vibration.

 

4. Seat Material–304 Stainless Steel

• Excellent Corrosion Resistance–304 stainless steel resists oxidation and corrosion in water, wastewater, and mild chemical environments.

• Durable Hard-Seal Performance–The metal-to-metal sealing interface provides superior wear resistance compared to soft-seat designs, making it ideal for higher temperatures and demanding service conditions.

• Long Service Life–The 304 seat maintains its sealing geometry over thousands of cycles, ensuring consistent bubble-tight shut-off.

 

5. Stem Material–SS420 Stainless Steel

• High Strength–Significantly higher tensile strength than 304/316 stainless steel, ensuring reliable torque transmission even in large-diameter valves.

• Wear Resistant–Hardened surface resists galling and fretting during repeated cycling.

• Blow-Out Proof Design–Retention mechanism prevents accidental stem ejection under pressure surges.

 

6. Electric Actuator with Worm Gear & Handwheel

• Electric Automation–Provides remote on-off or modulating control with 4-20 mA feedback for PLC and SCADA integration.

• Worm Gear Torque Multiplication–The worm gear reduces operating torque requirements, enabling smooth, reliable operation even in large-diameter valves.

• Manual Handwheel Override–Includes a handwheel for manual operation during power outages or maintenance–no special tools required.

• ISO 5211 Mounting–Standardized top flange ensures compatibility with a wide range of actuators.

 

 

Typical Applications

 

Why Choose Tianjin Worlds Valve?

1. LRQA-Certified Quality–Our ISO 9001:2015 certification is issued by LRQA, a globally trusted certification body–demonstrating our commitment to continuous improvement and risk management.

2. Double Offset Specialists–We have extensive experience manufacturing double offset butterfly valves for water, power, and industrial projects worldwide.

3. Wide Size Range–From DN100 to DN1800, we cover the full spectrum of industrial piping requirements.

4. Full Customization–Materials, flange standards (ANSI, DIN, JIS, BS), coatings (any RAL color), actuators–we build to your spec.

5. 19+ Years Export Experience–Smooth logistics and after-sales support to 50+ countries–including Europe, Americas, Middle East, and Southeast Asia.

6. 100% Traceability–Every valve comes with material certificates and pressure test reports–no exceptions.

7. Quick Turnaround–Dedicated project manager; typical lead time 15–40 days. Factory visits welcome in Tianjin.

 

Get in Touch–Customize Your Double Offset Valve Today:

Whether you need this 10-inch configuration, a different size within our DN100–DN1800 range, automated actuation, or a complete valve package for a large-scale project–we're ready to build to your specification.

Simply send us:

• Required size and pressure rating

• Media type and operating temperature

• Preferred material combination (body / disc / seat)

• Actuator type (manual, worm gear, electric, pneumatic, hydraulic)

• Flange standard and drilling (ANSI, DIN, JIS, BS)

• Target quantity and destination port

 

Our team will respond within 24 hours with a quotation and engineering proposal.

We also welcome factory visits–come see how we manufacture your valves in Tianjin, China.