Key Product Features
- Fluoropolymer lining helps isolate wetted metal surfaces from corrosive media
- Compact butterfly valve structure for chemical pipeline isolation
- Suitable for acid, alkali, solvent and corrosive liquid service after compatibility review
- PTFE, FEP, PFA or project-specific lining material options
- Manual lever, gear operator, pneumatic actuator or electric actuator options
- Wafer, lug, flanged or project-specific connection according to selected model
- Useful where rubber lining is not suitable for the chemical medium
- Lower space requirement compared with many full-body isolation valves
Product Configuration
| Configuration Item | Common Configuration | Project Options |
|---|---|---|
| Valve Type | PTFE lined butterfly valve | Wafer, lug, flanged or project-specific lined butterfly valve |
| Main Function | On-off isolation for corrosive chemical media | Manual or automated chemical isolation service |
| Lining Material | PTFE | FEP, PFA or project-specific fluoropolymer lining |
| Body Material | Cast iron, ductile iron or carbon steel with lining | Stainless steel or project-specified body material |
| Disc Material | PTFE-lined disc or corrosion-protected disc | Stainless steel, coated disc or project-specific disc material |
| Operation | Manual lever or gear operator | Pneumatic actuator, electric actuator or position feedback accessory |
| End Connection | Wafer or lug type | Double flanged or project-specific connection when available |
Technical Specifications
| Specification Item | Typical / Available Options |
|---|---|
| Product Type | PTFE lined butterfly valve / fluoropolymer lined butterfly valve |
| Primary Function | On-off isolation for corrosive chemical pipelines |
| Valve Design | Concentric lined butterfly valve or project-specific lined butterfly valve design |
| Size Range | According to selected product series and approved drawing |
| Pressure Rating | According to body design, lining material, temperature and project specification |
| Body Material | Cast iron, ductile iron, carbon steel, stainless steel or project-specified material |
| Lining Material | PTFE, FEP, PFA or selected fluoropolymer lining |
| Disc Material | PTFE-lined disc, stainless steel disc or project-specific corrosion-protected disc |
| Operation | Manual, pneumatic or electric operation |
| End Connection | Wafer, lug, flanged or project-specific connection according to selected model |
| Typical Media | Acid, alkali, solvent, chemical solution and corrosive liquid after compatibility review |
| Testing Reference | According to approved inspection specification and selected product standard where applicable |
Technical note: Do not publish fixed pressure, temperature, vacuum, chemical compatibility, lining thickness or leakage claims until the medium, concentration, temperature, pressure, lining material, disc design and project specification are confirmed.
How a PTFE Lined Butterfly Valve Works
A PTFE lined butterfly valve uses a quarter-turn disc to open or close the flow passage. When the disc is parallel to the pipeline, the valve allows flow. When the disc rotates 90 degrees, the valve closes against the lined seat or sealing surface.
The important difference is the fluoropolymer lining on the wetted internal surfaces. The corrosive medium should contact the PTFE, FEP or PFA lining instead of directly contacting the metal valve body. Lining continuity, disc sealing, shaft sealing and operating torque must be reviewed during selection.
PTFE Lined Butterfly Valve vs Rubber Lined Butterfly Valve
| Comparison Item | PTFE Lined Butterfly Valve | Rubber Lined Butterfly Valve |
|---|---|---|
| Main Lining Material | PTFE, FEP, PFA or selected fluoropolymer | EPDM, NBR, natural rubber, neoprene or other rubber lining |
| Main Selection Focus | Chemical corrosion resistance and lining integrity | Water, wastewater, mild slurry and selected corrosive media service |
| Typical Media | Acid, alkali, solvent and aggressive chemical liquid after review | Water, wastewater, seawater, cooling water and selected slurry service |
| Selection Risk | Permeation, vacuum, lining deformation and chemical compatibility | Rubber swelling, abrasion, aging, temperature and chemical compatibility |
| Quotation Requirement | Confirm chemical name, concentration, lining material and temperature | Confirm medium, solids content, rubber material and operating condition |
For rubber-lined butterfly valve options, review our Rubber Lined Butterfly Valve and EPDM Lined Butterfly Valve. For broader butterfly valve products, visit the Butterfly Valve category.
PTFE Lined Butterfly Valve vs PTFE Lined Ball Valve
| Comparison Item | PTFE Lined Butterfly Valve | PTFE Lined Ball Valve |
|---|---|---|
| Closing Element | Rotating disc | Rotating ball |
| Operation | Quarter-turn operation | Quarter-turn operation |
| Main Advantage | Compact structure and lower installation space for larger pipeline sizes | More enclosed ball port structure for selected chemical isolation service |
| Selection Focus | Disc lining, shaft sealing, seat design and torque | Ball port lining, seat design, body lining and torque |
For lined ball valve applications, review our PTFE Lined Ball Valve. For lined plug valve applications, see PTFE Lined Plug Valve.
Lining Material Selection
The lining material is the key corrosion-resistant barrier in a PTFE lined butterfly valve. Selection should be based on medium type, chemical concentration, temperature, pressure, permeation risk, vacuum condition, flow velocity and project specification.
| Lining Material | Typical Consideration |
|---|---|
| PTFE | Common fluoropolymer lining for many corrosive chemical services after compatibility review |
| FEP | Often considered where melt-processable fluoropolymer lining is required |
| PFA | Often considered for demanding chemical service where higher lining integrity is required |
| Modified PTFE | May be selected for specific sealing or chemical service requirements |
Typical Applications
Typical Applications- Chemical processing pipelines
- Acid and alkali transfer lines after material compatibility review
- Chlor-alkali and chemical dosing systems
- Pickling, plating and surface treatment lines
- Solvent and corrosive liquid transfer
- Corrosive wastewater and neutralization systems
- Fine chemical and process utility lines after specification review
- Skid-mounted chemical injection, dosing or storage systems
For broader chemical valve selection guidance, see Industrial Valves for Chemical Processing. For acid and alkali pipeline selection, see Corrosion-Resistant Valves for Acid and Alkali Pipelines.
Application Limits
- Not recommended for abrasive slurry with hard solids unless the lining and disc design are specifically reviewed.
- Not suitable for high-temperature steam service unless the selected lined valve design is approved for that condition.
- High vacuum service requires special review of lining support, adhesion and deformation risk.
- Permeating chemicals may require special lining material, thickness or construction review.
- Crystallizing media may affect disc rotation and sealing performance.
- Continuous throttling may damage the lining or sealing surface and is not recommended for standard on-off designs.
- Thermal cycling may affect lining stress, shaft sealing and disc torque.
- Do not claim universal chemical resistance without checking medium concentration and temperature.
Inspection and Documentation
| Inspection / Document | Purpose |
|---|---|
| Material Test Certificate | Confirms body, disc, shaft and pressure-containing material when required. |
| Lining Inspection | Checks lining continuity, surface defects, lining edges and exposed metal risk. |
| Dimensional Inspection | Checks end connection, face-to-face length, flange compatibility and valve marking. |
| Spark Test / Holiday Test | Checks lining integrity where required by project specification. |
| Shell Pressure Test | Verifies pressure-containing body integrity under agreed test condition. |
| Seat Leakage Test | Checks shut-off performance according to agreed inspection requirement. |
| Operation / Torque Test | Checks disc rotation, operating torque and actuator suitability. |
| Final Data Book | Collects drawings, certificates, inspection records, pressure test reports and packing documents. |
Export packing should protect flange faces, lining edges, disc sealing surfaces, shaft area, actuator interface and machined connection surfaces. Valves can be packed with flange covers, moisture-resistant wrapping, foam separation and reinforced plywood cases according to size and shipment method.
Information Required for Valve Selection
- Valve size and quantity
- Medium name, concentration and chemical composition
- Operating temperature and design temperature
- Operating pressure and design pressure
- Required lining material: PTFE, FEP, PFA or other fluoropolymer
- Required lining thickness or lining inspection requirement if specified
- Flow rate, flow velocity and pressure drop condition
- Solids content, crystallization risk or permeation risk
- Vacuum condition or negative pressure condition if applicable
- Connection standard and face-to-face requirement
- Manual, pneumatic or electric operation requirement
- Testing, documentation and third-party inspection requirement
FAQ
What is a PTFE lined butterfly valve used for?
A PTFE lined butterfly valve is used for on-off isolation in corrosive chemical pipelines where the internal wetted metal surfaces need fluoropolymer protection.
Is a PTFE lined butterfly valve the same as a rubber lined butterfly valve?
No. A PTFE lined butterfly valve uses fluoropolymer lining such as PTFE, FEP or PFA. A rubber lined butterfly valve uses rubber lining such as EPDM, NBR or natural rubber. They are selected for different media conditions.
Which lining material can be used?
PTFE, FEP, PFA or other fluoropolymer lining materials may be selected according to medium, concentration, temperature, pressure, permeation risk and project specification.
Can PTFE lined butterfly valves handle all chemicals?
No. Chemical compatibility must be checked according to chemical type, concentration, temperature, pressure and service condition. No lined valve should be described as universally resistant to all chemicals.
Can a PTFE lined butterfly valve be used for throttling?
Standard PTFE lined butterfly valves are mainly used for on-off isolation. Continuous throttling may damage the lining or sealing surface, so a control valve should be reviewed for demanding regulating service.
