Specification

10 Inch Dn250 Centerline Pneumatic Flange Soft Seal Ductile Iron Sewage butterfly Valve

I. Product Technical Overview

The Newway pneumatic flanged soft-seal concentric butterfly valve is specially designed for industrial fluid automation control. It adopts a concentric central line structure (with the stem axis, disc center, and pipeline centerline coaxial), covering DN50-DN400 (2″-16″) in diameter, suitable for PN16 (1.6MPa) pressure class. The applicable medium temperature ranges from -18℃ to 80℃ (with short-term resistance up to 120℃). The body uses QT450 ductile iron (tensile strength ≥450MPa, elongation ≥10%), the sealing seat adopts EPDM rubber, and it is matched with single-acting/double-acting pneumatic actuators, enabling precise shut-off and flow regulation for media such as water, sewage, oil, and gas. It is widely applied in municipal pipelines, sewage treatment, industrial water supply/drainage, and HVAC systems.

II. Core Product Features

(A) Concentric Central Line Structure Design

The Newway concentric butterfly valve achieves three technical advantages through its concentric layout:

Optimized Flow Path Efficiency

Geometric Coaxial Principle: The stem, disc, and pipeline centerline are completely concentric. When fully open, the disc aligns parallel to the fluid direction, with the flow coefficient Cv increased by 15% compared to eccentric structures (pressure loss of DN200 valve ≤0.3m water column), ideal for high-flow transportation (e.g., urban water main lines).

90° Precise On-Off: The disc completes opening/closing within a 90° rotation around the axis. A mechanical limit device ensures an angle error ≤1°, with the handle position directly corresponding to the opening degree for visual on-site monitoring.

Low Maintenance Cost

No Eccentric Friction: The sealing seat directly fits the disc edge without eccentric displacement, eliminating wear. The seat is fixed by a dovetail groove for online replacement (no pipeline disassembly needed), reducing maintenance time by 40%.

Simple Structure: 20% fewer mechanical components than double-eccentric designs reduce processing complexity and failure points, suitable for 24/7 continuous operation (e.g., sewage treatment plants).

Installation Compatibility

Standardized Flange Connection: Complies with GB/T 9113, ANSI B16.5, and other flange standards. Flange surface roughness Ra≤12.5μm, bolt hole spacing deviation ≤±0.3mm, adapting to global pipeline systems.

(B) High-Performance Material System

(C) Integrated Pneumatic Drive System

Actuator Configuration

Standard IP65-protected pneumatic actuator, optional single-acting (spring return)/double-acting, air source pressure 0.4-0.7MPa. Full stroke time for DN200 valve ≤8s, supporting 4-20mA position feedback.

Anodized aluminum cylinder with dual-piston rack-and-pinion mechanism ensures stable torque output (error ≤5%), compatible with DCS/PLC remote control.

Safety Redundancy Design

Optional manual handwheel (for DN≥150) enables manual operation during air source failure, complying with ISO 13849-1 safety standards.

Integrated limit switches and solenoid valves support 3-position control (“open-closed-stop”), meeting ESD system response time ≤3s.

Environmental Adaptability

Actuator built-in anti-freeze grease (-18℃~60℃ applicable). Stainless steel fasteners optional for coastal areas, resisting salt spray (GB/T 10125≥1000 hours).

Product Overview

III. Key Technical Attributes

IV. Manufacturing Processes and Quality Control

(A) Precision Processing Flow

Valve Body Casting and Treatment

Ductile iron uses lost foam casting, annealed at 900℃ to relieve stress, with graphite spheroidization rate ≥90%. Flange surfaces are machined by CNC gantry milling, flatness error ≤0.05mm.

Epoxy coating applied in two layers (primer + topcoat), tested by cross-cut (ISO 2409, adhesion grade 0).

Seal System Assembly

EPDM seal seat formed by compression molding (pressure ≥5MPa), interference fit clearance with body ≤0.02mm. Disc edge rounded (R≥3mm) to reduce seal wear during operation.

Each valve undergoes 1.5x nominal pressure hydrostatic test (30-min hold), leakage rate ≤5×10⁻⁸m³/s (EN12266 Class A).

Drive System Debugging

Pneumatic actuator undergoes 100 no-load cycles, positioning accuracy ±1%, torque decay ≤10%. Stability tested under simulated air source fluctuations (±10% pressure).

(B) Quality Certification System

Material Traceability: Key components with heat numbers, chemical reports (CMA certified), supporting third-party PMI testing.

Performance Certifications: Drinking water valves certified by WRAS, NSF61; marine models available with LR/DNV-GL classification.

After-Sales Guarantee: 18-month warranty, free replacement for seal failure, lifelong technical support (including seal replacement guidance videos).