TIANYU DI Lug-Type Flanged Midline Butterfly Valve – DN175 PN10 Aluminum Bronze Disc with Rubber Lining, Soft-Seal Flow Control Valve for Water, Sewage & Industrial Fluid Systems

I. Product Overview

II. Key Attribute Specifications

A. Dimensional & Pressure-Temperature Parameters

• Port Size: DN175 (7”), with a size range of DN50 to DN300 (2” to 12”) to meet diverse pipeline demands. The midline design ensures the disc is concentric with the seat, enabling full-bore flow when open and minimizing pressure drop (Cv value up to 350 for DN175).
• Pressure Rating: PN10 (1.0MPa), suitable for low-to-medium pressure systems. Hydrostatic testing follows API 598: 1.5× rated pressure (1.5MPa) for the valve body and 1.1× rated pressure (1.1MPa) for the seat, with no leakage or structural deformation permitted.
• Temperature Range: -10℃ to 90℃, limited by the rubber lining’s thermal stability—covering potable water, sewage, and most industrial fluids within moderate temperature thresholds.

B. Material Composition

• Valve Body: Ductile Iron (DI, ASTM A536 Grade 65-45-12) offers high tensile strength (≥650MPa), ductility, and impact resistance. It is optimized for corrosion resistance in water and sewage environments, with a blue epoxy paint coating for external protection.
• Butterfly Disc: Aluminum Bronze (ASTM B148 C95400), a copper-alloy with aluminum (8-12%), iron, and nickel additions. It provides superior corrosion resistance in water (including seawater) and excellent wear resistance, extending disc life in cyclic operations.
• Sealing Material: EPDM or NBR rubber lining, bonded to the valve body and seat. EPDM is standard for potable water (FDA-compliant) and high-temperature tolerance, while NBR suits oil-resistant applications. The lining is precision-molded for uniform thickness and adhesion.
• Valve Stem: Stainless Steel (304 or 316) features a corrosion-resistant surface, anti-blowout design, and polished finish (Ra ≤0.8μm) to minimize friction with packing.
• Lug Flanges & Fasteners: Integral DI lugs (machined to AWWA C504/EN 593 standards) and stainless steel (304) bolts/nuts ensure corrosion resistance in wet environments.

C. Connection & Operational Features

• Connection Type: Lug-Type Flange (AWWA C504/EN 593) allows installation with through-bolts or stud bolts, simplifying retrofitting and confined-space installations.
• Operation Mode: Manual (worm gear operator as standard) with optional pneumatic, electric, or hydraulic actuation. The worm gear operator reduces torque by 5-10 times, enabling single-person operation of DN175 valves.
• Functional Features:
  • Midline Design: Concentric disc-seat alignment ensures uniform sealing pressure, reducing seat wear and extending seal life.
  • Soft Seal Integrity: Rubber-lined seat achieves ANSI/FCI Class VI leakage performance, preventing media loss in potable water or sewage applications.
  • Corrosion Resistance: Aluminum bronze disc and DI body with epoxy coating resist corrosion from water, sewage, and mild chemicals.

D. Certifications & Compliance

• Design & Manufacturing Standards: API 609, AWWA C504, EN 593.
• Quality & Safety Certifications: ISO 9001, WRAS (optional), NSF 61 (optional).
• Performance Certifications: ANSI/FCI Class VI (leakage), ISO 6283 (flow coefficient testing).

III. Feature Description

A. Midline (Concentric) Design: Uniform Sealing & Low Torque

• Uniform Seat Wear: Even contact pressure across the sealing surface eliminates uneven wear, extending seal life by 2-3 times in cyclic operations (e.g., municipal water distribution).
• Low Operational Torque: Concentric alignment reduces friction, requiring only 80-100 N·m of torque for a DN175 worm gear model—enabling manual operation without specialized tools.
• Full-Bore Flow: When fully open, the disc is parallel to the flow, minimizing pressure drop and reducing pumping energy costs by 15-20% compared to restrictive valves.

B. Material Synergy: Corrosion Resistance & Durability

• Ductile Iron Body: DI’s ductility absorbs shock and vibration, making it ideal for municipal pipelines subject to ground movement. In buried water mains, DI valves withstand soil settlement without cracking, unlike brittle cast iron alternatives.
• Aluminum Bronze Disc: The alloy’s corrosion resistance in water is unmatched, making it suitable for seawater or brackish applications (e.g., coastal sewage treatment). In marine outfall systems, it operates reliably for 10 years, while carbon steel discs corrode within 3 years.
• Rubber Soft Seal: EPDM/NBR lining provides elastic sealing that compensates for misalignments or surface imperfections. In potable water systems, EPDM’s FDA compliance ensures no contamination, and its resilience extends service life in systems with occasional particulates.

C. Lug-Type Connection: Installation Flexibility

• Versatile Mounting: Installation with through-bolts or stud bolts simplifies retrofitting older pipelines, where matching flange bolt patterns is challenging.
• Easy Maintenance: Valves can be removed for maintenance without disturbing adjacent pipeline flanges, reducing downtime in water treatment plants.
• Space Optimization: Lug valves require less axial space than wafer or flanged valves, making them ideal for cramped urban piping vaults.

D. Soft Seal Performance: Leak-Tight Reliability

• Bubble-Tight Sealing: ANSI/FCI Class VI performance ensures ≤0.1×DN mm³/min leakage for water—critical for potable water and sewage systems to prevent contamination or environmental discharge.
• Thermal & Chemical Compatibility: EPDM resists oxidation, ozone, and most water-based chemicals (pH 5-9), while NBR suits oil-resistant industrial wastewater.
• Resilience to Minor Damage: The rubber seal’s elasticity recovers from minor abrasions, extending service life in systems with occasional particulate matter (e.g., sand in well water).

IV. Manufacturing Processes

A. Material Inspection & Preparation

• DI Verification: Spectral analysis confirms chemical composition, and ultrasonic testing detects internal defects. Mechanical testing ensures compliance with ASTM A536.
• Aluminum Bronze Validation: Disc blanks are tested for chemical composition and hardness to ensure corrosion and wear resistance.
• Rubber Lining Checks: EPDM/NBR rubber is tested for hardness, tensile strength, and elongation to ensure sealing integrity.

B. Valve Body & Disc Fabrication

• Body Manufacturing: DI bodies are sand-cast, shot-blasted, and CNC-machined to meet AWWA C504 flatness and surface finish standards.
• Disc Fabrication: Aluminum bronze discs are precision-turned and milled for concentricity with the stem, with a sharp yet durable edge profile.
• Rubber Lining Application: The body’s seat area is grit-blasted, then EPDM/NBR rubber is bonded via heat and pressure for uniform thickness and adhesion.

C. Assembly & Quality Testing

• Stem & Disc Assembly: The stainless steel stem is keyed to the disc, tested for concentricity (runout ≤0.1mm).
• Hydrostatic Testing: Per API 598, the body is tested at 1.5× PN10, and the seat at 1.1× PN10, with no leakage allowed.
• Operational Testing: The valve is cycled 100 times to verify smooth operation, torque, and seal integrity.

D. Final Inspection & Documentation

• Visual Inspection: Checks for surface defects, proper marking, and compliance with AWWA C504.
• Documentation: Includes MTRs, hydrostatic test reports, and compliance certificates (API 609, ISO 9001, WRAS/NSF 61 optional).

V. Product Advantages

A. Cost-Effective Water & Sewage Control

B. Extended Service Life in Water Environments

C. Leak-Tight Reliability for Potable Water & Sewage

D. Easy Installation & Maintenance

E. Versatility Across Water-Related Industries

VI. Product Applications

A. Municipal Water & Wastewater

• Potable Water Distribution: Regulates flow in city water mains with FDA-compliant EPDM lining.
• Sewage Treatment Plants: Controls influent, effluent, and sludge flow with corrosion-resistant aluminum bronze discs.
• Stormwater Management: Manages runoff in urban drainage systems with rugged DI construction.

B. Industrial Water Systems

• Process Water Circulation: Regulates cooling and process fluid flow in manufacturing facilities.
• Fire Protection Systems: Serves as isolation valves in sprinkler and standpipe systems.
• Agricultural Irrigation: Controls water flow in canals and sprinkler systems with efficient midline design.

C. Commercial & Institutional Facilities

• Building Services: Manages hot/cold water flow in hospitals, schools, and offices.
• Food & Beverage Processing: Regulates potable water and cleaning fluids with FDA-compliant sealing.
• Recreational Facilities: Controls water flow in pools, fountains, and water parks with corrosion-resistant materials.

VII. Customization