Specification

TIANYU Large-Diameter Concentric Soft-Seal Flanged Butterfly Valve:with Replaceable Seat, Low Torque, Bare Shaft, zero Leakage

I. Product Technical Positioning

The TIANYU large-diameter concentric soft-seal flanged butterfly valve is specially designed for fluid control in large pipe diameters ranging from DN300 to DN2400 (12″ to 96″). Adopting a concentric structure (with the stem, disc, and pipeline centerline coaxial), it uses ductile iron (DI) or stainless steel (CF8/CF8M) as the main material, suitable for PN10-PN16 (1.0-1.6MPa) pressure classes. The valve connects to pipelines via double flanges (complying with EN1092 standards) and can be equipped with worm gear, electric, or pneumatic drives. It is ideal for high-flow applications in water treatment, municipal pipe networks, oil & gas transportation, and building HVAC systems, especially for clean media like water, air, and oil at normal to medium temperatures (-20°C to 120°C).

II. Core Product Features

(A) Concentric Structure & Soft Seal Design

Concentric Layout:
The stem axis aligns with the disc center and pipeline centerline. The disc rotates around the axis, completing opening/closing within a 90° stroke, featuring a simple structure and low flow resistance (flow coefficient Cv ≥10,000, pressure loss ≤0.5m water column for DN1000).
Replaceable Soft Seal Seat:
The seat uses EPDM/NBR rubber (compression set ≤8% at 120°C×72h), fixed by dovetail grooves or pressure rings for online replacement when worn, reducing maintenance costs by 40% compared to hard-seal valves. The rubber-clad disc edge ensures zero-leakage sealing (leakage rate ≤5×10⁻⁸m³/s, conforming to EN12266).

(B) U-Section Flange & Low-Torque Operation

U-Section Flange Structure:
The valve body flange adopts a U-shaped cross-section design to enhance structural rigidity for large diameters (flange thickness ≥34mm for DN1000), reducing deformation during bolt tightening. It complies with EN558-1 Series 20 face-to-face dimensions for strong installation compatibility.
Low-Torque Operation:
The worm gear reducer (ratio 1:30-1:60) uses a bronze worm wheel + 45# steel worm shaft, surface carburized (hardness HRC55-60). Manual operation torque for DN1000 ≤150N·m, electric actuator full-stroke time ≤20s, adapting to rapid response needs of automation systems.

(C) Material System & Application Adaptability

Component	Material	Performance Indicators
Body	Ductile Iron QT450-10	Tensile strength ≥450MPa, impact energy ≥27J at -20°C
Disc	Ductile Iron/304 SS	Surface roughness Ra≤3.2μm, erosion resistance +30%
Seat	EPDM/NBR Rubber	Temperature -20°C~120°C, chloride ion corrosion resistant
Stem	2Cr13 Stainless Steel	Trapezoidal thread accuracy 6g, quenched & tempered HB220-250

III. Key Technical Parameters

Parameter Category	Technical Indicators	Expansion Options
Nominal Size	DN300-DN2400 (12″-96″)	Custom DN2600-DN3000 (engineering evaluation)
Pressure Rating	PN10-PN16 (1.0-1.6MPa)	High-pressure PN25 (2.5MPa)
Connection Type	Double Flange (EN1092)	Butt weld, socket weld (ASME B16.25)
Actuation	Manual Worm Gear/Electric/Pneumatic	Hydraulic actuator, explosion-proof (Ex d IIC T6)
Sealing Standard	EN12266 Class A/B	Fire certification API 607 (metallic seal redundancy)
Testing Standard	API 598, EN12266	Low-temperature testing (-40°C, requires material upgrade)

Product Overview

IV. Manufacturing Processes & Quality Control

(A) Precision Manufacturing Flow

Body Casting & Machining:
- Ductile iron bodies use lost foam casting, annealed at high temperature to relieve stress, with graphite spheroidization rate ≥90%. 100% ultrasonic testing (UT) after machining, surface roughness Ra≤12.5μm.
- Flange surfaces are machined by CNC gantry milling, flatness error ≤0.05mm, bolt hole spacing deviation ≤±0.3mm to ensure installation tightness.
Disc & Seat Assembly:
- The disc undergoes dynamic balance testing (residual unbalance ≤5g·cm). Rubber seats are molded under pressure, with interference fit clearance ≤0.02mm to the body. Each valve undergoes 1.5x nominal pressure hydrostatic test (30-min hold) and 1.1x air pressure test (helium leak detection).
Drive System Debugging:
- Worm gear meshing clearance controlled at 0.05-0.1mm. Electric actuators undergo 100 no-load cycle tests, positioning accuracy ±1%, torque overload protection set at 1.2x rated value.

(B) Quality Certification System

Material Traceability: Key components come with heat numbers and CMA-certified chemical reports, supporting third-party PMI testing.
System Certifications: Holds ISO 9001, CE-PED; drinking water products comply with WRAS; marine models can provide DNV-GL, LR classification certifications.
After-Sales Guarantee: 18-month warranty, free replacement for leakage due to process issues, lifelong maintenance technical support.

Valve Details

VI. TIANYU Brand Customization Advantages

Based in Wenzhou’s smart manufacturing base, TIANYU offers end-to-end customization for large-diameter concentric butterfly valves:

Deep Material Customization: Supports special materials like duplex steel (2205), Hastelloy C276 for harsh media, providing corrosion simulation test reports.
Drive System Expansion: Can integrate intelligent electric actuators (with Modbus), pneumatic diaphragm actuators (with positioners), or manual emergency devices for explosion-proof, fire-proof scenarios.
Certification & Standard Adaptation: Provides API, JIS, GOST custom designs, WRAS/NSF61 drinking water certifications, and classification society approvals (LR, ABS).
Rapid Delivery System: 25-day standard lead time, 15-day small-batch customization (≥1 unit), 72-hour emergency channel with real-time production tracking.
Global Service Network: Technical service centers in APAC, Europe, North America offer on-site installation guidance, maintenance training, 24/7 emergency response, with critical spares delivered via airfreight within 48 hours.

Application

. Product Application Scenarios

(A) Municipal Water Supply/Drainage

In urban main water transmission pipes (DN1000-DN1400), TIANYU valves’ EPDM seats meet drinking water safety standards. The U-flange design adapts to frequent disassembly needs of municipal pipes. In a provincial capital’s South-to-North Water Diversion project, DN1200 valves operated leak-free for 3 years at 1.0MPa, reducing maintenance costs by 60% compared to gate valves.

(B) Industrial Circulating Water Systems

In thermal power plant circulating water pipes (DN800-DN2000), ductile iron bodies with epoxy coating (thickness ≥200μm) resist cooling water corrosion. Electric actuators integrate with DCS systems for automatic cooling tower water flow regulation. In a 300MW unit, valves responded within ≤15s to match unit load changes.

(C) Oil & Gas Storage/Transportation

In refinery gas pipelines (DN600-DN1200, PN16), NBR seats resist hydrocarbon media, and worm gear drives allow manual operation in explosion-proof areas. A petrochemical enterprise uses DN1000 valves for gas emission control, achieving zero-leakage shut-off via API 598 testing.

(D) Building HVAC Systems

In commercial complex air conditioning chilled water pipes (DN300-DN800), low torque reduces electric actuator power demand by 25%, integrating with BA systems for variable flow control. A skyscraper project using DN600 valves reduced system energy consumption by 12%, with U-flanges saving 30% installation space.