Specification

DN250 PN16 Pneumatic High-Temp Hard Sealed Triple Eccentric Butterfly Valve

I. Product Overview

TIANYU DN250 PN16 pneumatic high-temperature hard sealed butterfly valve is a robust flow control device engineered for medium to large-diameter industrial pipelines. Integrating a triple eccentric structure and metal hard sealing, it delivers reliable shut-off and regulation under high-temperature conditions. Driven by a pneumatic actuator, it enables automated, rapid operation, while its stainless steel construction ensures resistance to corrosion, pressure, and wear. Suitable for handling water, air, gas, and other high-temperature media, it serves as a critical component in metallurgy, petrochemical, power, and heating systems where efficiency and durability are paramount.

II. Key Attribute Parameters

Size Range: Focus on DN250 (10″), with compatibility extending to DN50~DN400 (2″~16″) to cover diverse pipeline needs.
Pressure Rating: PN16 (1.6MPa), designed to withstand stable and fluctuating pressures in medium-pressure systems.
Temperature Range: -40℃~400℃, supported by high-temperature-resistant metal seals and stainless steel materials to resist thermal deformation.
Material Configuration:
- Valve Body & Disc: Stainless steel (304/316) with thickened walls, ensuring structural rigidity under thermal stress and corrosion resistance.
- Seal Surface: Metal hard sealing (stainless steel + alloy coating) for tightness, achieving zero leakage even at extreme temperatures.
- Pneumatic Actuator: ATD-160 model (for DN250), aluminum alloy housing with heat-resistant diaphragms, providing 90° rotation in 5~10 seconds.
Connection Type: Flange (RF per ANSI B16.5), with precise bolt hole alignment for secure integration with DN250 pipelines.
Operation: Pneumatic, compatible with 4~20mA signals for proportional control; manual override included for emergency use.
Standards Compliance: Design per API 609, EN 593; testing per API 598; actuator rated IP65 for dust and water resistance.

Product Overview

III. Structural Features

Triple Eccentric Design: Three offsets minimize friction between the disc and seat during 90° of operation, ensuring the disc tightens as it closes. For DN250, this reduces wear and ensures bubble-tight shut-off—critical for preventing high-temperature media leakage.
Pneumatic Actuation: The ATD-160 actuator delivers sufficient torque to operate DN250 valves efficiently, enabling rapid response to process changes (e.g., steam flow adjustments in power plants).
Hard Sealing Structure: Metal-to-metal sealing surfaces (Ra ≤0.8μm) resist oxidation and wear, maintaining integrity even after 100,000+ cycles in high-temperature environments.
Stainless Steel Build: Low thermal expansion coefficient minimizes deformation under temperature fluctuations, ensuring consistent performance in DN250 pipelines handling hot media.
Optimized Flow Path: Streamlined disc design reduces pressure drop by 15% compared to standard valves, improving energy efficiency in large-diameter systems.

IV. Manufacturing Processes

Material Inspection: DN250 stainless steel castings undergo spectral analysis (304: 18-20% Cr) and ultrasonic testing to eliminate internal defects, ensuring high-temperature stability.
Precision Machining: CNC grinders shape the triple eccentric disc and body to ±0.05mm tolerances, critical for DN250’s sealing accuracy. Eccentric parameters are calibrated via 3D measurement.
Seal Enhancement: Metal sealing surfaces receive Stellite coating (hardness ≥55 HRC) via plasma spraying, then are lapped for uniform contact with the disc.
Actuator Integration: The ATD-160 actuator is mounted via an ISO 5211 flange, ensuring precise alignment with the DN250 valve stem. Actuators undergo torque and response testing.
Performance Validation: Each DN250 valve undergoes hydrostatic tests (2.4MPa) and high-temperature seal tests (400℃ steam) to confirm zero leakage and structural integrity.

Valve Details

V. Product Advantages

DN250-Specific Efficiency: Optimized for medium-large pipelines, balancing flow capacity with tight sealing—ideal for systems requiring high throughput (e.g., industrial heating mains).
High-Temp Reliability: Metal hard sealing withstands 400℃, outperforming soft seals in steam or hot gas applications, reducing maintenance in critical systems.
Automated Precision: Pneumatic actuation enables rapid, remote control, reducing human intervention and improving process responsiveness in large-diameter lines.
Durable Construction: Stainless steel and hard sealing extend service life to 15+ years, lowering replacement costs for DN250 pipelines in harsh environments.
Versatile Compatibility: Handles water, air, gas, and mild corrosives, adapting to metallurgy, petrochemical, and power sectors with minimal modification.

Application

VI. Application Fields

Metallurgy: Controls high-temperature air and cooling water in DN250 rolling mill lines, withstanding thermal cycling and particulate media.
Petrochemical: Regulates gas flow in DN250 refinery process loops, where corrosion resistance and rapid shut-off prevent hazardous leaks.
Power Generation: Manages steam in DN250 boiler auxiliary systems, ensuring stable operation under high-temperature, high-pressure conditions.
Heating Networks: Regulates hot water in DN250 district heating mains, with pneumatic control adapting to fluctuating demand efficiently.