TIANYU DN1400 (56″) CLASS 150 WCB Hard Seal Butterfly Valve: Triple Eccentric Metal-Sealed Flanged Valve for Large-Diameter Industrial Media with Fire-Safe & Long-Life Performance

I. Product Overview

TIANYU DN1400 (56″) CLASS 150 WCB hard seal butterfly valve is a heavy-duty flow control solution engineered exclusively for large-diameter industrial applications requiring reliable performance under medium pressure and diverse temperature conditions. As a triple eccentric (offset) hard seal butterfly valve, it features a precision-engineered design that eliminates contact between the disc and seat during most of the opening/closing stroke, delivering exceptional wear resistance and sealing integrity—critical for large-diameter systems where maintenance and replacement are costly.

Constructed from WCB carbon steel (ASTM A216), this valve adheres to international standards including API 609, ASME B16.34, and ASME B16.5, ensuring seamless integration with global large-scale industrial pipelines. The flanged connection (ANSI B16.5) enables secure installation, while the metal-to-metal hard seal (Stellite 6 cobalt-based alloy) provides reliable performance in temperatures ranging from cryogenic lows to moderate highs. Equipped with optional fire-safe and anti-static features, it addresses safety concerns in hazardous environments—making it a trusted choice for municipal infrastructure, power generation, water treatment, and large industrial fluid management. Whether isolating large-volume media, regulating high-flow pipelines, or ensuring system integrity in critical processes, this valve embodies durability, precision, and operational reliability tailored to the unique demands of DN1400 (56″) diameter applications.

II. Key Attribute Specifications

A. Dimensional & Pressure-Temperature Parameters

Port Size: DN1400 (56″), a large-diameter specification designed for high-flow industrial and municipal pipelines. This size caters to applications requiring massive media throughput, such as large water treatment plants, power plant cooling systems, and municipal water distribution mains.
Pressure Rating: CLASS 150 (2.0MPa), aligned with medium-pressure industrial requirements for large-diameter systems. The valve undergoes hydrostatic testing at 1.5× rated pressure for the body and 1.1× rated pressure for the seat, ensuring structural integrity and leak-tight sealing in high-flow, medium-pressure environments.
Temperature Range: -29℃ to 425℃, optimized for WCB carbon steel’s thermal stability and the metal hard seal’s performance limits. This range supports cryogenic fluids (e.g., chilled water in industrial cooling systems), ambient media (e.g., potable water), and moderately heated processes (e.g., low-pressure steam auxiliary lines).

B. Material Composition

Valve Body & Disc: WCB carbon steel (ASTM A216), featuring tensile strength of 485–655MPa and yield strength ≥240MPa. WCB is ideal for large-diameter valves due to its excellent weldability, cost-effectiveness, and resistance to moderate corrosion, thermal stress, and mechanical impact—critical for the structural demands of DN1400 size.
Seal & Disc Hardfacing: Stellite 6 (cobalt-chromium alloy) applied to the disc and seat sealing surfaces. Stellite 6 delivers hardness ≥58 HRC, exceptional wear resistance, and chemical inertness to most industrial media, including water, steam, oil, and mild chemicals.
Valve Stem: Alloy steel (42CrMo or 17-4PH), precision-machined with an anti-blowout design to prevent stem ejection under pressure. The material resists corrosion, wear, and thermal deformation, ensuring stable operation even in the high-torque scenarios of large-diameter valves.
Gaskets & Fasteners: Spiral-wound metal gaskets (stainless steel with graphite filler) for body-bonnet sealing, paired with high-strength alloy steel fasteners (ASTM A193 B7) to maintain sealing integrity under thermal cycling and pressure fluctuations common in large pipelines.

C. Connection & Operational Features

Connection Type: Flanged ends (ANSI B16.5, Raised Face/RF), compliant with large-diameter pipeline standards. The RF flange design ensures secure gasket seating, even under the vibration and pressure fluctuations of high-flow systems, while the bolt-through configuration simplifies alignment during installation.
Operation Mode: Worm gear manual operation as standard, with optional pneumatic or electric actuation for automated control. The worm gear operator reduces torque requirements by up to 70%, enabling single-person operation of the large DN1400 valve—critical for practical usability in industrial settings. Automated actuators (pneumatic double-acting/spring-return or electric multi-turn) support remote monitoring and integration with DCS/PLC systems.
Safety Features: Optional fire-safe design (API 607 compliant) and anti-static protection. The fire-safe structure ensures metal-to-metal sealing persists if seals are compromised in a fire, preventing catastrophic media leakage in large-diameter pipelines. Anti-static devices discharge static electricity, mitigating explosion risks in flammable media applications.

D. Certifications & Compliance

Industry Standards: API 609 (butterfly valves for industrial service), ASME B16.34 (valves—flanged, threaded, and welding end), ASME B16.5 (pipe flanges and flanged fittings), ISO 9001 (quality management system).
Material Certifications: ASTM A216 (WCB carbon steel), ASTM A193 (fasteners), ASTM A182 (alloy steel components).
Regional Approvals: CE (EU safety compliance), ATEX (optional for hazardous environments), SIL (Safety Integrity Level) certification for process safety applications.

III. Feature Description

A. Triple Eccentric Design: Critical for Large-Diameter Wear Reduction

The triple eccentric (offset) design is indispensable for DN1400 large-diameter valves, addressing the unique challenge of seal wear in high-flow, high-cycle applications. The disc is offset radially, axially, and angularly, creating a conical sealing surface that lifts completely away from the seat during the opening/closing stroke—eliminating rubbing contact for over 90% of the movement.

In large water treatment plants, where the valve may cycle daily to regulate flow, this design reduces seal wear by up to 90% compared to single or double eccentric alternatives. The disc only makes contact with the seat at the final moment of closure, where metal-to-metal pressure (aided by spring loading) forms a tight seal. This mechanism extends seal life to 5–8 years in heavy-duty service, drastically reducing the need for costly maintenance on large-diameter valves that require specialized equipment for access.

B. Metal-to-Metal Hard Seal: Reliability in Large-Scale Systems

The Stellite 6 hard seal is tailored to the demands of DN1400 valves, providing unmatched durability in high-flow, medium-pressure environments. Unlike soft seals that degrade under the velocity and potential particulate load of large-diameter pipelines, Stellite 6 maintains its hardness and sealing integrity up to 425℃. In municipal water distribution mains, for example, the hard seal resists abrasion from suspended solids (e.g., sand, sediment) that would quickly damage soft seals, ensuring leak-tight performance for years.

The hard seal delivers ANSI/FCI Class IV leakage performance, a critical specification for large-diameter valves where even minor leakage can result in significant media loss. In a power plant’s cooling water system, this level of sealing prevents waste of thousands of gallons of water daily, supporting sustainability and cost-efficiency.

C. WCB Carbon Steel Construction: Structural Integrity for Large Diameters

WCB carbon steel is the ideal material for DN1400 valves, balancing structural strength, weldability, and cost-effectiveness. Large-diameter valve bodies require material that can withstand the mechanical stress of high-flow media (e.g., water hammer in pipelines) and the weight of the valve itself. WCB’s tensile strength and ductility prevent brittle fracture, while its weldability allows for on-site modifications or repairs—critical for large valves that are difficult to transport and replace.

The valve body is manufactured via sand casting, optimized for large-diameter components to ensure uniform wall thickness (minimum 30mm for DN1400 CLASS 150) and eliminate internal defects. Post-casting heat treatment (normalizing) relieves internal stresses, preventing warping during operation and maintaining dimensional accuracy for proper sealing.

D. Worm Gear Operation: Practical Usability for Large Valves

Manual operation of a DN1400 valve is only feasible with a worm gear operator, which reduces torque requirements by leveraging gear reduction. Without this feature, the torque needed to open/close the valve would require multiple operators or specialized equipment. The worm gear operator’s robust design (cast iron housing, precision-machined gears) ensures smooth operation even after years of use, with minimal maintenance (annual lubrication only).

For automated systems, the valve’s modular design allows integration with large-torque pneumatic or electric actuators. Pneumatic actuators are ideal for high-cycle applications (e.g., wastewater treatment plants), while electric actuators with 4–20mA control signals enable precise flow modulation in power plant cooling systems, integrating seamlessly with SCADA systems.

E. Flanged Connection: Secure Installation for Large Pipelines

Flanged connections (ANSI B16.5) are essential for DN1400 valves, providing a secure, leak-tight joint that can withstand the pressure and vibration of large-diameter pipelines. The bolt-through design ensures the valve is evenly clamped between pipeline flanges, eliminating misalignment that could cause leakage. For retrofitting projects, the flanged connection ensures compatibility with existing ANSI-standard pipelines, avoiding the need for costly adapter fittings.

In municipal water mains, the flanged design simplifies installation using standard pipeline construction equipment, reducing downtime during system upgrades. The raised face (RF) flange paired with spiral-wound gaskets creates a robust seal that resists the cyclic pressure changes common in water distribution systems.

Large-Diameter Triple Eccentric Hard Seal Butterfly Valve

IV. Manufacturing Processes

A. Material Inspection & Preparation

Raw Material Verification: WCB carbon steel billets undergo rigorous testing to ensure compliance with ASTM A216. Spectral analysis confirms chemical composition (C: 0.25–0.35%, Mn: 0.60–1.00%), while ultrasonic testing (UT) detects internal defects (porosity, cracks) that could compromise structural integrity in large-diameter components.
Hardfacing Material Testing: Stellite 6 alloy is tested for chemical composition (Co: 50–60%, Cr: 25–30%) via X-ray fluorescence (XRF) and hardness (≥58 HRC) via Rockwell testing, ensuring wear resistance meets industrial standards.

B. Valve Body & Disc Fabrication

Casting: The DN1400 valve body and disc are produced via sand casting, using precision patterns to ensure dimensional accuracy. The mold design incorporates risers to prevent shrinkage defects in thick-walled sections (e.g., flange areas). Castings are cleaned via shot blasting to remove scale and surface impurities.
Heat Treatment: Cast components undergo normalizing (900–950℃, air-cooled) to relieve internal stresses and improve mechanical properties. This step is critical for large-diameter components, as unrelieved stress can cause warping during machining or operation.
Machining: CNC milling and turning centers precision-machine the valve body, disc, and flange faces. The triple eccentric geometry is machined to within ±0.05mm tolerance, ensuring the disc lifts correctly from the seat. Flange faces are machined to flatness tolerance ≤0.05mm/m and surface finish Ra ≤3.2μm for proper gasket seating.

C. Hardfacing & Sealing Surface Preparation

Hardfacing Application: Stellite 6 is applied to the disc and seat sealing surfaces via plasma transfer arc (PTA) welding. The process is automated to ensure uniform layer thickness (3–5mm) and minimal heat input, preventing distortion of large-diameter components.
Finishing: Hardfaced surfaces are precision-ground and lapped to achieve a surface finish of Ra ≤0.8μm, ensuring uniform contact between the disc and seat. This step is verified via blueing (contact pattern testing) to confirm ≥95% seal contact.

D. Assembly & Quality Testing

Component Assembly: The disc, stem, worm gear operator, and sealing components are assembled in a dedicated large-diameter valve assembly area. The stem is aligned to ensure axial runout ≤0.05mm, preventing binding during operation. The worm gear is lubricated with high-temperature grease to reduce friction.
Hydrostatic Testing: The valve undergoes shell testing at 1.5× CLASS 150 rated pressure (3.0MPa) and seat testing at 1.1× rated pressure (2.2MPa), with a 30-minute hold time for each test. No leakage, sweating, or deformation is allowed. Testing is documented via pressure gauges and visual inspection.
Operational Testing: The valve is cycled 100 times to verify smooth operation and torque consistency. The worm gear operator is tested to ensure it can fully open/close the valve within 50–60 turns, a practical limit for manual operation.
Non-Destructive Testing (NDT): Critical welds (e.g., body-bonnet joints) undergo magnetic particle testing (MPI) to detect surface cracks. Large cast sections are inspected via ultrasonic testing (UT) to confirm internal integrity.

E. Final Inspection & Documentation

Visual Inspection: The valve is inspected for surface defects, proper marking (size, pressure rating, material, serial number), and compliance with ASME B16.34.
Documentation: Each valve is accompanied by a Material Test Report (MTR) for WCB steel, hydrostatic test report, and compliance certificates (API 609, ISO 9001).

Large-Diameter DN1400 CLASS150 WCB Triple Eccentric Metal-Sealed Hard Seal Butterfly Valve

V. Product Advantages

A. Large-Diameter Optimized Design

The triple eccentric design and Stellite hard seal are tailored to DN1400 applications, reducing wear and extending service life by 5–8 years—critical for large valves where maintenance requires specialized equipment and significant downtime.

B. Cost-Effective Durability

WCB carbon steel offers a balance of performance and cost, making large-diameter valves affordable without compromising structural integrity. The valve’s long service life and minimal maintenance requirements reduce total cost of ownership by 30–40% compared to valves with exotic materials.

C. Reliable Leak-Tight Sealing

ANSI/FCI Class IV leakage performance prevents significant media loss in large-diameter systems, supporting sustainability and cost-efficiency. In municipal water mains, this translates to thousands of gallons of water saved annually.

D. Practical Operation

The worm gear operator enables single-person manual operation, while optional automated actuators support remote control—adapting to the diverse needs of large industrial and municipal facilities.

E. Seamless Integration

Flanged ANSI B16.5 connections ensure compatibility with existing large-diameter pipelines, simplifying installation and retrofitting. This interchangeability reduces project delays and costs associated with custom fittings.

F. Safety Compliance

Optional fire-safe and anti-static features meet API 607 and ATEX standards, ensuring regulatory compliance in hazardous environments such as oil refineries or chemical plants with large-diameter fluid lines.

VI. Product Applications

A. Municipal Water & Wastewater Treatment

Water Distribution Mains: DN1400 valves regulate flow in large municipal water supply networks, ensuring reliable water delivery to residential, commercial, and industrial areas. The hard seal resists abrasion from sediment, while the flanged connection simplifies integration with existing pipelines.
Wastewater Treatment Plants: Controls flow of raw sewage, treated effluent, and sludge in large-scale treatment facilities. The triple eccentric design prevents clogging from solids, and the WCB construction resists corrosion from organic matter.

B. Power Generation

Cooling Water Systems: Manages flow of cooling water in thermal and nuclear power plants, where large-diameter pipelines are required to dissipate heat from turbines. The valve’s medium-pressure rating (CLASS 150) and temperature range (-29℃ to 425℃) suit cooling water operating conditions.
Auxiliary Steam Lines: Regulates low-pressure steam flow in power plant auxiliary systems (e.g., boiler feedwater heating). The Stellite hard seal withstands moderate steam temperatures and prevents leakage.

C. Industrial Manufacturing

Chemical Processing Plants: Controls flow of large volumes of mild chemicals, solvents, and process fluids in petrochemical or bulk chemical facilities. The WCB construction and Stellite seal ensure compatibility with most industrial media.
Pulp & Paper Mills: Regulates flow of water, pulp slurry, and chemical bleaching agents in large-scale paper production. The triple eccentric design prevents clogging from pulp fibers, and the hard seal resists corrosion from bleaching chemicals.

D. Oil & Gas Industry

Midstream Pipeline Infrastructure: Isolates sections of large-diameter pipelines transporting crude oil, refined products, or natural gas. The flanged connection ensures secure sealing, while optional fire-safe features mitigate risks in hazardous areas.
Refinery Auxiliary Lines: Controls flow of cooling water, fuel oil, and process fluids in refinery auxiliary systems. The valve’s large diameter supports high-flow requirements, and the WCB construction withstands industrial rigor.

E. Infrastructure & Construction

Irrigation Systems: Regulates flow in large agricultural irrigation networks or municipal park irrigation systems requiring high-volume water delivery. The valve’s durable design withstands outdoor environmental conditions.
Industrial Facility Pipelines: Manages flow of water, air, or process fluids in large manufacturing complexes (e.g., automotive plants, steel mills) with extensive pipeline networks.

VII. Customization

TIANYU DN1400 (56″) CLASS 150 WCB hard seal butterfly valve delivers reliable, long-lasting flow control for large-diameter industrial and municipal applications. Its triple eccentric design, Stellite hard seal, WCB construction, and flanged connection ensure wear resistance, leak-tight performance, and seamless integration, backed by API/ASME standards.

Customize with 304/316 stainless steel for enhanced corrosion resistance, extended temperature range (-40℃~500℃) with alloy steel components, pneumatic/electric actuators for automation, fire-safe/anti-static features, or JIS/GB flange standards. Tailor to your media type, flow requirements, and safety needs for optimal large-diameter pipeline performance.

Large-Diameter DN1400 CLASS150 WCB SS Triple Eccentric Metal-Sealed Hard Seal Butterfly Valve