Specification

TIANYU Ductile Iron/Cast Steel Electric Flanged Double Eccentric Soft Seal Butterfly Valve for Water, Air, Oil, and Weakly Corrosive Fluids

I. Product Overview

TIANYU electric flanged double eccentric soft seal butterfly valve is a high-performance industrial valve engineered with a double eccentric structure, designed for efficient flow control in diverse medium and normal temperature environments. Constructed with ductile iron or cast steel bodies and soft rubber seals, this valve combines compact design, reliable sealing, and electric actuation to meet the demands of water supply and drainage, industrial processing, and fluid transmission systems. Its 90-degree rotational operation ensures quick shutoff and precise regulation, while the double eccentric design enhances sealing stability—critical for applications where leakage prevention and long service life are paramount. Whether integrated into water plants, power stations, steel mills, or chemical facilities, this valve delivers consistent performance, adapting seamlessly to media such as water, air, gas, oil, and weakly corrosive fluids.

II. Key Attributes and Specification Parameters

1. Basic Attributes

Structure: Double eccentric design, where the valve shaft and butterfly plate are offset by two distinct eccentricities. This structure minimizes friction between the sealing surfaces during operation, enabling “tighter sealing as it closes” and reducing wear on the soft seal.
Body Material: Available in ductile iron (QT450-10) and cast steel (WCB), with optional cast iron (HT200, HT250) for cost-sensitive applications. Ductile iron offers excellent toughness and impact resistance, while cast steel provides higher strength for medium-pressure systems.
Sealing Material: Soft rubber seals, including nitrile rubber (NBR), ethylene propylene diene monomer (EPDM), silicone rubber, fluororubber (FKM), and PTFE. These materials are selected for their elasticity, chemical resistance, and compatibility with different media.
Pressure Rating: 1.0MPa and 1.6MPa, suitable for medium-pressure industrial pipelines and water supply systems.
Port Size: DN50 to DN2000 (equivalent to 2in to 80in), covering small to extra-large pipeline diameters to accommodate diverse flow requirements.
Temperature Range: Dependent on sealing material:
- Nitrile rubber: -40℃ to 90℃ (ideal for oil and water-based media)
- Fluororubber: -20℃ to 200℃ (suitable for higher-temperature fluids and weakly corrosive media)
Media Compatibility: Versatile for water (industrial, municipal), air, natural gas, mineral oil, and weakly corrosive fluids (e.g., dilute chemicals), ensuring adaptability across industries.
Connection Form: Flanged ends, conforming to GB/T 9113 and GB/T 17241.6 standards, facilitating secure integration into existing pipeline systems.
Driving Mode: Electric actuation, featuring a motorized mechanism that enables remote or automated control of the 90-degree butterfly plate rotation. This ensures precise operation and reduces manual effort, ideal for large-diameter valves or automated systems.
Warranty: Backed by a 1-year warranty, ensuring reliability and providing assurance for long-term industrial use.

2. Detailed Specification Parameters

Design and Manufacturing Standard: GB/T 12238
Flange Connection Standard: GB/T 9113, GB/T 17241.6
Structure Length Standard: GB/T 12221
Testing and Inspection Standard: GB/T 13927
Valve Shaft Material: 2Cr13 (stainless steel, offering corrosion resistance and structural strength)
Packing Material: Flexible graphite, ensuring stem sealing to prevent external leakage.
Pressure Testing Parameters:
- Sealing test: 0.66MPa (for 1.0MPa rating), 1.1MPa (for 1.0MPa rating), 1.76MPa (for 1.6MPa rating)
- Strength test: 0.9MPa (for 1.0MPa rating), 1.5MPa (for 1.0MPa rating), 2.4MPa (for 1.6MPa rating)
Leakage Rate: Complies with GB/T 13927, ensuring minimal to zero leakage under rated conditions.

Product Overview

III. Product Features

TIANYU electric flanged double eccentric soft seal butterfly valve is distinguished by features that enhance its performance, reliability, and adaptability in industrial applications:

Double Eccentric Sealing Excellence: The dual eccentricity design ensures the butterfly plate contacts the seal only at the final stage of closure, reducing friction and wear during operation. This “progressive sealing” mechanism ensures tighter shutoff as the valve closes, critical for preventing leakage in water and oil systems.
Versatile Soft Seal Options: Rubber seals (NBR, EPDM, FKM, etc.) provide excellent elasticity and conformability, enabling reliable sealing even with minor pipeline misalignments. The ability to choose seal materials based on media type (e.g., FKM for high temperatures, NBR for oil) enhances the valve’s versatility.
Flexible Seal Placement: Rubber O-ring can be mounted on either the valve body or the butterfly plate, allowing customization for specific media characteristics. For example, body-mounted seals suit abrasive fluids, while plate-mounted seals simplify maintenance in clean water systems.
Robust Butterfly Plate Design: The butterfly plate adopts a frame structure, combining high strength with a large flow area to minimize pressure drop. This design ensures efficient fluid transmission, reducing energy consumption in pumping systems.
Corrosion Resistance: The valve body undergoes overall baking paint treatment, forming a protective layer against rust and environmental degradation. This extends service life, especially in outdoor or humid environments.
Bidirectional Sealing: The valve body features bidirectional sealing capability, eliminating installation restrictions related to media flow direction or spatial orientation. This simplifies on-site installation and reduces errors.
Electric Actuation Convenience: Electric drive enables remote control and integration with automated systems, ideal for large-diameter valves (DN2000) or hard-to-reach locations. The motorized mechanism ensures smooth, consistent operation with precise flow regulation.

IV. Manufacturing Process

TIANYU adheres to strict manufacturing protocols to ensure the quality and performance of its double eccentric soft seal butterfly valves:

Material Selection and Inspection: Raw materials (ductile iron, cast steel, rubber) undergo rigorous testing. Ductile iron is inspected for tensile strength and impact resistance, while cast steel undergoes chemical composition analysis to verify compliance with WCB standards. Rubber seals are tested for elasticity, temperature resistance, and chemical compatibility with target media.
Precision Casting and Machining: Valve bodies and butterfly plates are produced via precision casting to ensure dimensional accuracy. CNC machining centers are used to refine flange surfaces, shaft holes, and seal grooves, maintaining tolerances within ±0.05mm to ensure proper alignment of the double eccentric structure.
Seal Fabrication and Assembly: Rubber seals are molded to precise dimensions, with FKM and NBR seals undergoing vulcanization processes to enhance elasticity and durability. During assembly, the butterfly plate is aligned with the valve shaft to ensure accurate eccentricity, and the electric actuator is calibrated to achieve smooth 90-degree rotation with minimal backlash.
Surface Treatment: The valve body is cleaned and coated with anti-corrosive baking paint, applied in multiple layers to ensure uniform coverage. This treatment resists salt spray, moisture, and industrial fumes, extending service life in harsh environments.
Testing and Quality Control: Each valve undergoes comprehensive testing in accordance with GB/T 13927:
- Strength tests verify the body’s integrity under 1.5 times the nominal pressure.
- Sealing tests (conducted at 1.1 times the nominal pressure) ensure zero leakage.
- Operation tests validate the electric actuator’s performance, including response time and rotational accuracy.

Valve Details

V. Product Advantages

TIANYU electric flanged double eccentric soft seal butterfly valve offers numerous advantages that make it a preferred choice for industrial flow control:

Superior Sealing Reliability: The double eccentric design and soft rubber seals ensure bubble-tight shutoff, critical for water supply systems where leakage can lead to resource waste or system inefficiency. This reliability is maintained even after thousands of operations.
Extended Service Life: Reduced friction from the eccentric design, combined with corrosion-resistant materials and durable rubber seals, extends the valve’s service life. The frame-style butterfly plate resists deformation, further enhancing longevity.
Energy Efficiency: The large flow area and minimal flow resistance reduce pressure loss in pipelines, lowering energy consumption for pumps and compressors—a key advantage in high-flow applications like water treatment plants.
Easy Installation and Maintenance: Bidirectional sealing and flanged connections simplify installation, while the option to mount seals on the body or plate eases replacement. The electric actuator’s modular design allows for quick repair or upgrade without disassembling the entire valve.
Broad Application Flexibility: Compatibility with diverse media (water, air, oil, weak corrosives) and a wide size range (DN50-DN2000) make the valve suitable for industries from power generation to food processing, eliminating the need for specialized valves in mixed systems.
Cost-Effective Performance: Ductile iron and cast steel options balance durability and cost, while the long service life and low maintenance requirements reduce lifecycle expenses—ideal for budget-conscious projects.

Application

VI. Product Applications

TIANYU electric flanged double eccentric soft seal butterfly valve is widely used across industries that require efficient flow control of medium and normal temperature fluids:

Water Treatment and Supply: Deployed in water plants, municipal water supply networks, and wastewater treatment facilities, where reliable sealing and large flow capacity are essential for regulating water distribution.
Power Generation: Used in cooling water systems, boiler feed lines, and condensate circuits of power stations, handling water and steam (within temperature limits) with precise flow control.
Steel and Metallurgy: Integrated into cooling circuits, process water lines, and lubricating oil systems in steel mills, where the valve’s corrosion resistance and high strength withstand industrial operating conditions.
Chemical and Pharmaceutical: Suitable for weakly corrosive fluid transmission (e.g., dilute acids, solvents) in chemical processing and pharmaceutical production, with FKM seals ensuring compatibility with mild chemicals.
Paper and Food Industries: Applied in pulp processing water systems and food-grade fluid lines, where clean operation and easy maintenance meet hygiene requirements.
HVAC and Building Services: Used in heating, ventilation, and air conditioning systems to regulate water and air flow, with electric actuation enabling integration into smart building automation systems.

TIANYU electric flanged double eccentric soft seal butterfly valve, with DN50-DN2000 sizes and 1.0/1.6MPa pressure, suits water, air, oil, weak corrosives. Ductile iron/cast steel body, rubber seals, and electric actuation ensure reliable sealing and easy control. Ideal for water plants, power stations, and more. Customizable (sizes, seals) to meet specific needs.