Specification

TIANYU Aluminum Bronze Multi-Level Hard Seal Gear-Operated Lug-Type Triple Offset Butterfly Valve

I. Product Overview

TIANYU aluminum bronze multi-level hard seal gear-operated lug-type triple offset butterfly valve is a high-performance flow control solution engineered for large-diameter, demanding pipeline systems. Designed to balance robust sealing, corrosion resistance, and operational efficiency, it integrates triple offset geometry, aluminum bronze construction, and multi-level hard seals to handle abrasive media, high temperatures, and corrosive environments. Suitable for municipal water treatment, marine and offshore, industrial processes, and thermal systems, this valve delivers reliable shut-off and flow regulation in applications where durability and zero leakage are critical. Its lug-type design and gear operation simplify installation and maintenance, making it a versatile choice for large-scale infrastructure and industrial projects.

II. Key Attribute Specifications

Category	Details
Size Range	DN50~DN1200 (2″~48″), with a focus on large-diameter applications (e.g., DN600) for high-flow pipeline systems.
Pressure Rating	Class 150~600 (2.0MPa~10.0MPa), accommodating moderate to high-pressure systems in industrial and municipal settings.
Temperature Range	-20°C~425°C, suitable for both cryogenic and high-temperature media (e.g., chilled water, steam, thermal fluids).
Design Standards	AWWA C504 (municipal waterworks), ASME B16.34 (valve dimensions), API 609 (butterfly valves for pipeline service).
Material Composition	– Body & Lug: Aluminum bronze (ASTM B148 C95800), an alloy with high copper content (≥85%) plus aluminum, iron, and nickel, offering exceptional corrosion resistance in saline and wet environments. – Disc: K400 (austenitic manganese steel), featuring high hardness (HB ≥400) and toughness, resistant to abrasion from solids and slurries. – Seal: Multi-level hard seal with alloy coating (e.g., nickel-chromium or stellite), providing metal-to-metal sealing and resistance to high temperatures and wear. – Stem & Gear: Stainless steel (316) for corrosion resistance, ensuring smooth operation in harsh environments.
Connection Type	Lug-type (per AWWA C504/ASME B16.1), with bolt holes in lugs aligning with pipeline flanges. Enables installation between flanges without full disassembly and allows unilateral maintenance.
Actuation	Manual gear operation (standard), reducing torque by 30~50% for easy handling of large-diameter valves. Optional pneumatic or electric actuators (ISO 5211 mounting) for automated control in industrial systems.
Performance Metrics	– Leakage Class: ANSI/FCI Class V (zero leakage under test pressure), critical for hazardous or valuable media. – Hydrostatic Test: Body tested at 1.5×rated pressure (e.g., 3.75MPa for Class 150) for 30 minutes. – Seal Test: Zero leakage verified with air/nitrogen at 1.1×rated pressure (e.g., 2.75MPa for Class 150). – Cycle Life: ≥100,000 operations with K400 disc maintaining integrity in abrasive media.

Product Overview

III. Feature Description

A. Triple Offset Geometry

The valve incorporates a triple offset design, where the disc axis is offset from the valve body axis (first offset), the disc sealing surface is offset from the disc axis (second offset), and the sealing cone angle is offset from the pipeline axis (third offset). This configuration eliminates metal-to-metal contact between the disc and seat during rotation, reducing friction and wear. As the valve closes, the disc rotates into a precise, linear contact with the multi-level seal, ensuring uniform pressure distribution across the sealing surface—critical for achieving zero leakage in high-pressure applications (e.g., industrial steam lines). Unlike concentric or double offset designs, triple offset minimizes seal deformation, extending service life in cyclic operations.

B. Aluminum Bronze Corrosion Resistance

Constructed from ASTM B148 C95800 aluminum bronze, the valve body and lugs excel in corrosive environments, particularly saline or wet conditions. The alloy’s aluminum content forms a protective oxide layer, resisting pitting and crevice corrosion from seawater, chlorinated water (municipal treatment), and mild acids. In marine applications (e.g., ballast systems or seawater intake), this eliminates the need for external coatings, reducing maintenance costs. Compared to carbon steel or cast iron, aluminum bronze also offers high strength-to-weight ratio, ensuring structural integrity in large-diameter (DN600+) valves without excessive weight.

C. Multi-Level Hard Seal System

The multi-level hard seal features a series of alloy-coated metal ridges, creating a labyrinth effect that blocks media flow at multiple points. This design enhances sealing reliability by distributing pressure across the seal, preventing leakage even if one level is compromised. The alloy coating (e.g., stellite) resists high temperatures (up to 425°C) and abrasion from particulate media (e.g., sewage solids, mining slurries). Unlike soft seals (PTFE), hard seals avoid degradation in high-temperature or aggressive chemical environments, making the valve suitable for industrial processes involving steam, hydrocarbons, or acidic fluids.

D. Lug-Type Installation & Maintenance

Lug-type design integrates threaded bolt holes in the valve lugs, aligning with pipeline flanges for secure mounting. This allows the valve to be installed between flanges without requiring full pipeline disassembly, simplifying retrofits in existing systems. The design also enables unilateral maintenance: if one flange side is inaccessible (e.g., buried pipelines), the valve can be removed from the accessible side, reducing downtime in critical infrastructure (e.g., municipal water mains).

E. Gear-Operated Efficiency

Manual gear operation reduces torque requirements by leveraging gear reduction, enabling one-person operation of large-diameter valves (e.g., DN600). The gear housing is sealed to protect internal components from debris, moisture, and corrosion, ensuring smooth operation in outdoor or dirty environments (e.g., construction sites, mining facilities). For automated systems, optional pneumatic or electric actuators integrate with PLC/DCS controls, enabling remote operation and real-time flow monitoring—ideal for industrial processes requiring precise flow modulation.

F. K400 Disc Wear Resistance

The valve disc is crafted from K400 (austenitic manganese steel), a material renowned for work hardening: as abrasive particles (e.g., sand, slurry solids) impact the surface, the disc hardness increases (HB ≥400), resisting wear over time. In applications like sewage treatment or mining slurry lines, this extends disc life by 2~3 times compared to standard stainless steel, reducing replacement frequency and maintenance costs. The disc’s smooth, precision-machined surface also minimizes pressure drop, optimizing flow efficiency in large-diameter pipelines (e.g., water distribution mains).

IV. Manufacturing Processes

A. Material Preparation & Quality Validation

Alloy Verification: Aluminum bronze castings (body, lugs) and K400 discs undergo spectral analysis to confirm chemical composition—ensuring compliance with ASTM B148 (C95800) and K400 standards (e.g., manganese content ≥11%).
Defect Detection: Ultrasonic testing and dye penetrant inspection identify internal/external defects (e.g., porosity, cracks) in cast components, critical for maintaining pressure integrity in high-pressure applications.
Heat Treatment: K400 discs undergo solution annealing to enhance toughness, ensuring they withstand impact from abrasive media without fracturing.

B. Precision Machining

CNC Machining: Valve body, disc, and seal surfaces are machined using 5-axis CNC centers to tight tolerances (±0.05mm). This ensures precise alignment of the triple offset geometry, critical for reducing friction and achieving uniform sealing.
Seal Groove Fabrication: Multi-level seal grooves are milled into the valve body, with each ridge machined to exact dimensions (height, width) to create the labyrinth effect.
Lug & Flange Machining: Lug bolt holes are drilled and tapped per AWWA C504 standards, with chamfered edges to simplify bolt insertion during installation. Flange faces are machined to Ra ≤3.2μm for compatibility with pipeline gaskets.

C. Seal Assembly & Coating

Multi-Level Seal Fabrication: Metal seal components are precision-bent and welded to the valve body, ensuring each ridge is concentric with the disc path. The seals then undergo alloy coating (e.g., stellite welding) to enhance hardness and corrosion resistance.
Coating Cure: Coated seals are heat-treated to bond the alloy to the base metal, preventing flaking in high-temperature or abrasive environments.

D. Assembly & Actuator Integration

Disc & Stem Assembly: The K400 disc is mounted to the stainless steel stem, with bearings to minimize rotational friction. The stem is sealed with graphite packing to prevent media leakage while maintaining smooth operation.
Gear Operator Installation: Gear components (pinion, worm) are assembled and lubricated with high-temperature grease, then sealed in a weatherproof housing. Torque testing ensures the gear system reduces operating force by 30~50% as specified.

E. Performance Testing

Hydrostatic Body Test: The valve body is pressurized to 1.5×rated pressure (e.g., 3.75MPa for Class 150) for 30 minutes, with no visible leakage or deformation.
Seal Leak Test: Under 1.1×rated pressure (e.g., 2.75MPa for Class 150) using air or nitrogen, the valve must achieve ANSI/FCI Class V leakage (zero measurable leakage).
Cycle Test: The valve undergoes 10,000+ open-close cycles with abrasive media to verify seal and disc durability, ensuring performance remains consistent over time.
Torque Verification: Gear-operated valves are tested to confirm operating torque stays within specified limits (e.g., ≤500N·m for DN600), ensuring ease of manual operation.

Valve Details

V. Product Advantages

A. Extended Service Life in Harsh Environments

Aluminum bronze’s corrosion resistance and K400’s wear resistance reduce maintenance frequency by 50% compared to stainless steel valves in marine or abrasive applications. In a 5-year study of municipal sewage systems, TIANYU valves required only 1~2 seal replacements, versus 4~5 for standard butterfly valves.

B. Zero Leakage for Safety & Efficiency

Multi-level hard seals and triple offset design achieve ANSI/FCI Class V leakage, preventing costly media loss (e.g., industrial chemicals) or environmental contamination (e.g., sewage). In offshore oil platforms, this compliance avoids regulatory fines and ensures operational safety.

C. Energy & Cost Savings

The valve’s streamlined disc design and low pressure drop (≤0.07MPa at rated flow) reduce pump energy consumption by 10~15% in large-diameter water distribution systems. Lug-type installation also cuts labor costs by 40% compared to flanged valves, as it eliminates the need for full pipeline disassembly.

D. Versatility Across Industries

With a wide temperature range (-20°C~425°C) and pressure rating (Class 150~600), the valve adapts to diverse applications: from cryogenic brine lines in food processing to high-temperature steam lines in power plants. Its corrosion resistance makes it equally suitable for freshwater, seawater, and mild chemical media.

E. Reliable Automation Compatibility

Optional pneumatic/electric actuators integrate seamlessly with industrial control systems, enabling precise flow modulation (0~100%) and remote monitoring. In smart water networks, this allows real-time adjustment of flow rates based on demand, optimizing system efficiency.

Application

VI. Product Applications

A. Municipal Water & Wastewater Treatment

Raw Water Intake: Controls flow from rivers or reservoirs, with aluminum bronze resisting corrosion from organic acids and minerals.
Treated Water Distribution: Regulates flow in large-diameter mains (DN600+), ensuring consistent pressure across urban networks.
Sewage & Sludge Handling: K400 disc withstands abrasion from solids, while multi-level seals prevent leakage of contaminated fluids.

B. Marine & Offshore

Ballast Systems: Manages seawater intake/discharge, with aluminum bronze resisting saltwater corrosion and biofouling.
Bilge & Waste Discharge: Ensures zero leakage of oily wastewater, complying with MARPOL regulations.
Offshore Platforms: Controls flow of drilling fluids and produced water, with high-temperature compatibility for thermal processes.

C. Industrial Processes

Refining & Petrochemicals: Regulates hydrocarbon flow in pipelines, with hard seals resisting chemical degradation and high temperatures (up to 425°C).
Mining & Minerals: Handles abrasive slurries (e.g., coal, mineral concentrates), where K400 disc reduces wear from particulate impact.
Power Generation: Controls cooling water and steam flow in thermal power plants, with gear operation simplifying manual overrides during outages.

D. Fire Protection & Infrastructure

Fire Main Systems: Provides reliable shut-off in large-diameter fire suppression lines, with lug-type design enabling quick maintenance.
District Heating/Cooling: Modulates flow of hot/cold water in urban thermal networks, with high-temperature seals ensuring efficiency.

TIANYU aluminum bronze triple offset butterfly valve: DN50~DN1200, Class150~600, -20°C~425°C. Features multi-level hard seals, K400 disc, lug-type design, and gear operation. Ideal for municipal, marine, industrial applications requiring corrosion resistance and zero leakage.

Customize with: 316 stainless steel disc for extreme corrosion, PTFE-coated seals for chemical compatibility, explosion-proof electric actuators, or custom lug spacing for unique flanges. Tailored to your media, pressure, and automation needs.

DN600 Class150 Aluminum Bronze Multi-Level Hard Seal Gear Lug-Type Triple Offset Butterfly Valves