Specification

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

I. Product Overview

Newway 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.