Specification

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

I. Product Technical Positioning

The Newway 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

III. Key Technical Parameters

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.