Utmost Flow Control Technology Co., Ltd.
Utmost Flow Control Technology Co., Ltd.

Fluorine-Lined Butterfly Valves: A Comprehensive Guide

A fluorine-lined butterfly valve is a type of valve that is designed to handle highly corrosive fluids. The valve body and disc are lined with a fluoropolymer material, such as PTFE (polytetrafluoroethylene), PFA (perfluoroalkoxy), or FEP (fluorinated ethylene propylene), which are highly resistant to a wide range of chemicals. This makes them ideal for use in applications such as the chemical processing, pharmaceutical, and semiconductor industries.

Design and Construction:

  • Valve Body: The valve body is typically made of cast iron, cast steel, or stainless steel. The fluoropolymer liner is applied to the inside of the body using a variety of methods, such as sintering, extrusion, or spray coating.

  • Disc: The disc is also made of a metal material and is lined with the same fluoropolymer material as the body. The disc rotates on a shaft that is connected to an actuator.

  • Sealing: The valve seat is typically made of the same fluoropolymer material as the liner. The disc and seat form a tight seal when the valve is closed, preventing leakage.

  • Actuator: The actuator can be manual, pneumatic, hydraulic, or electric. It opens and closes the valve by rotating the disc.

Advantages of Fluorine-Lined Butterfly Valves:

  • Excellent corrosion resistance: Fluoropolymers are some of the most corrosion-resistant materials available. They can withstand exposure to a wide range of chemicals, including acids, bases, and solvents.

  • Leak-proof sealing: The tight seal between the disc and seat prevents leakage, even at high pressures and temperatures.

  • Lightweight and compact: Butterfly valves are lighter and more compact than other types of valves, such as globe valves and ball valves. This makes them easier to install and maintain.

  • Low maintenance: Fluoropolymer liners are self-lubricating and require minimal maintenance.

  • Bi-directional flow: Butterfly valves can handle flow in either direction.

  • Cost-effective: Fluorine-lined butterfly valve is often more cost-effective than other types of valves for corrosive applications.

Disadvantages of Fluorine-Lined Butterfly Valves:

  • Limited pressure and temperature ratings: Fluoropolymer liners can soften or melt at high temperatures. They are also not as strong as metal valves and may not be suitable for high-pressure applications.

  • Not suitable for abrasive fluids: Fluoropolymer liners can be abraded by slurries or other abrasive fluids.

  • Limited size range: Butterfly valves are typically available in smaller sizes than other types of valves.


Fluorine-lined butterfly valve is used in a wide range of applications, including:

  • Chemical processing: For handling corrosive chemicals such as acids, bases, and solvents.

  • Pharmaceutical: For handling pharmaceutical products and intermediates.

  • Semiconductor: For handling ultrapure water and other critical fluids.

  • Pulp and paper: For handling bleaching chemicals and other corrosive fluids.

  • Food and beverage: For handling food and beverage products.

  • Water treatment: For handling chlorinated water and other corrosive fluids.

Selection Considerations:

When selecting a fluorine-lined butterfly valve, it is important to consider the following factors:

  • The type of fluid being handled: Make sure the valve is compatible with the specific chemicals that it will be exposed to.

  • The pressure and temperature: Choose a valve with pressure and temperature ratings that are higher than the maximum conditions that it will see in service.

  • The flow rate: Select a valve that is sized correctly for the desired flow rate.

  • The actuator type: Choose an actuator that is compatible with your control system and has the required torque output.

Compared with Ball Valves:

FeatureFluorine-Lined Butterfly ValveBall Valve
Disc/Ball MaterialMetal lined with fluoropolymer (PTFE, PFA, FEP)Metal (stainless steel, bronze, etc.)
Sealing MechanismDisc and seat contactBall and seat contact
Corrosion ResistanceExcellent (fluoropolymer liner is highly resistant to most chemicals)Good (metal body may corrode depending on specific material and fluid)
Abrasion ResistanceLimited (fluoropolymer can be abraded by slurries)Good (metal is more resistant to abrasion)
Pressure RatingLower (typically up to 300 psi)Higher (typically up to 1500 psi)
Temperature RatingLower (typically up to 200°C)Higher (typically up to 400°C)
Leakage RateVery low (can be zero-leakage with proper design)Low (tight shut-off, but small leaks possible)
Flow Rate CapabilityHigh (bi-directional flow)Moderate (uni-directional flow)
Size RangeWide range (typically up to 48 inches)Wide range (typically up to 48 inches)
CostMore cost-effective for corrosive applicationsMore expensive than butterfly valves
MaintenanceLow (fluoropolymer is self-lubricating)Moderate (periodic lubrication and seal replacement)
ApplicationsChemical processing, pharmaceutical, semiconductor, pulp & paper, food & beverage, water treatmentGeneral purpose, oil & gas, power generation, mining


Fluorine-lined butterfly valves are a versatile and cost-effective solution for handling corrosive fluids. They offer excellent corrosion resistance, leak-proof sealing, and low maintenance. However, it is important to carefully consider the application requirements and select a valve that is properly sized and rated for the intended use.

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