Fluorine-Lined Butterfly Valve Product

Fluorine-Lined Butterfly Valve Product Manual
I. Product Overview
The fluorine-lined butterfly valve is a concentric-type on-off/control valve designed for highly corrosive industrial applications. The valve body utilizes cast iron, carbon steel, or stainless steel as the base material, while all wetted parts (body, disc, and seat) are fully lined with fluoroplastic. The medium contacts only the fluoroplastic layer throughout operation, completely isolating the metal substrate; this ensures exceptional resistance to acids, alkalis, oxidation, and solvents.
Featuring a concentric (non-eccentric) structure, the valve offers 90° rotation for opening and closing, high flow capacity, minimal flow resistance, a compact face-to-face dimension, and light weight. It is suitable for both rapid shut-off and flow regulation. Supporting manual, pneumatic, and electric automated control, it is a widely used, cost-effective anti-corrosion valve for piping systems in chemical processing, environmental protection, desulfurization, and pharmaceutical industries.
Applicable temperature range: -29°C to 250°C (depending on the specific lining material).
II. Lining Material Specifications (F4 / F46 / PFA)

1. PTFE (F4 – Polytetrafluoroethylene)
   Offers the strongest corrosion resistance, non-stick properties, and excellent self-lubrication. Applicable temperature: -29°C to 200°C. Suitable for standard strong acids and alkalis, as well as media prone to crystallization or adhesion.
2. F46 (FEP – Fluorinated Ethylene Propylene)
   Features excellent moldability, uniform lining thickness, high toughness, peel resistance, and vacuum resistance; resistant to delamination and cracking. Applicable temperature: -29°C to 200°C. Suitable for negative pressure, vacuum, and frequent cycling (opening/closing) applications.
3. PFA (Perfluoroalkoxy – Melt-processable Fluoroplastic)
   A premium anti-corrosion material offering superior resistance to permeation and creep, as well as excellent high-temperature performance. With a maximum temperature rating of 250°C, it is ideal for demanding conditions involving high temperatures, strong corrosives, high-purity chemicals, and precision processes. III. Structural Features

• Fully Fluoroplastic-Lined Anti-Corrosion Structure: The valve body, disc, and seat are entirely lined with fluoroplastic; the process medium does not come into contact with metal, completely eliminating issues such as body corrosion, rusting, and leakage caused by perforation.
• Centric Sealing & Effortless Operation: Features a symmetrical centric structure requiring low operating torque; operation is smooth and jam-free, with uniform sealing contact achieving Class VI zero-leakage performance.
• Excellent Flow Characteristics: Unobstructed flow path with minimal resistance and a high flow coefficient; resistant to material buildup and clogging, making it suitable for transporting sewage, slurries, and crystallizing media.
• ​​Multiple Structural Configurations: Available in wafer, flanged, and lug styles, ensuring easy installation and broad pipeline compatibility.
• Robust One-Piece Stem Design: Integrated stem construction offers high strength and prevents stem blowout or external leakage, ensuring safe and stable operation.
• Automation-Ready: Compatible with manual worm gear, pneumatic, or electric actuators; can be equipped with solenoid valves, limit switches, and smart positioners to enable remote automatic control and regulation. IV. Technical Parameters
• Nominal Diameter: DN50–DN600
• Pressure Rating: PN10, PN16, PN25, Class 150LB
• Liner Material: PTFE (F4), F46, PFA
• Operating Temperature: -29°C to 200°C (F4/F46); -29°C to 250°C (PFA)
• Connection Type: Wafer, Flanged, Lug
• Actuation: Manual (worm gear), Pneumatic, Electric
• Sealing Class: Class VI (Soft seal, zero leakage)
• Body Material: Ductile Iron, WCB Carbon Steel, 304 Stainless Steel
  V. Applicable Operating Conditions and Media
  ✅ Applicable Conditions
• Chemical & Fine Chemical Industries: Hydrochloric acid, dilute sulfuric acid, nitric acid, hydrofluoric acid, caustic soda, various salt solutions, strong oxidizers, organic solvents
• Environmental Protection & Wastewater: Electroplating wastewater, pickling wastewater, chemical wastewater, desulfurization/denitrification slurry, corrosive water containing chlorine
• Pharmaceutical, Agrochemical & Dye Industries: Transport and shut-off of corrosive raw materials, intermediates, and waste liquids
• Chlor-alkali, New Energy, Pickling Processes, Vacuum/Negative Pressure Pipelines
• Anti-corrosion fluid pipelines requiring non-stick, anti-crystallization, and zero-leakage properties
  ❌ Inapplicable Conditions
• Hard large particles, sharp sand/gravel, media causing strong erosion/abrasion (risk of scratching the liner)
• Ultra-high temperature molten alkali metals, pure liquid fluorine media
• Conditions exceeding the material’s temperature or pressure limits
  VI. Standards
• Design & Manufacturing: GB/T12238, HG/T3704
• Flange Standards: HG20592, ASME B16.5
• Pressure testing: GB/T13927, API 598
• Sealing standard: Class VI (zero leakage)
  VII. Installation and Operation Instructions
• Before installation, clear the pipeline of welding slag and hard debris to avoid scratching the fluoroplastic lining and sealing surfaces.
• Ensure proper pipeline alignment during installation; avoid forced prying or misalignment-induced squeezing, which could cause the lining to detach or crack.
• For high-temperature applications, a gradual temperature rise is recommended to prevent lining delamination or blistering caused by sudden temperature fluctuations.
• For negative pressure or vacuum pipelines, F46 or PFA linings are preferred due to their superior peel resistance.
• When transporting media prone to crystallization or adhesion over long periods, operate the valve periodically to prevent scaling or jamming.
• Keep the valve fully open during pressure testing; do not subject the sealing surface to high-pressure impact while the valve is fully closed.
  VIII. Product Advantages
  Fluorine-lined butterfly valves feature light weight, high flow capacity, low flow resistance, and rapid operation. The fully fluorinated lining ensures comprehensive corrosion resistance against various media, with an operating temperature range of -29°C to 250°C. Compared to fluorine-lined ball valves, they offer better cost-effectiveness and space-saving installation. Suitable for the shut-off and regulation of most acidic and alkaline corrosive fluids, they are a preferred choice for general-purpose industrial piping requiring corrosion resistance.