Corrosion-Resistant Wafer Butterfly Valve — Continuous PTFE Liner on WCB Body

The corrosion-resistant wafer butterfly valve with PTFE liner combines the mechanical strength of a WCB carbon steel body with the full chemical protection of a PTFE (Polytetrafluoroethylene) inner lining. The PTFE liner completely covers the inside of the metallic body — including the disc sealing seat — protecting the WCB from direct contact with corrosive fluids that would destroy uncoated steel. The SS316 stainless steel disc completes the protection of metal exposed to the fluid in the open position.

It is the lowest-cost-per-diameter solution for isolating moderately corrosive fluids in lines from DN50 to DN400 where PFA anti-corrosion ball valves are disproportionately expensive. For extremely aggressive fluids (HF, concentrated ClO₂, H₂SO₄ >70%), the correct alternative is the PFA-lined corrosion-resistant ball valve →

Construction Materials

• Body: WCB Carbon Steel — mechanical support structure. The metal has no contact with the fluid.
• Inner Liner: Molded PTFE (Polytetrafluoroethylene) — completely covers the inside of the body and forms the disc sealing seat. Virtually universal chemical resistance for moderately corrosive fluids.
• Disc: SS316 Stainless Steel — the only metallic component in contact with the fluid in the open position. Available with PTFE coating on the disc for greater resistance in fluids that attack SS316.
• Shaft / Stem: SS316 Stainless Steel with PTFE seals at the ends

Technical Specifications

• Mounting Type: Wafer — between DIN PN10/16 or ANSI 150 flanges
• Nominal Pressure: PN10 / PN16
• Operating Temperature: -20 °C to +150 °C with PTFE liner
• Available Diameters: DN50 (2") to DN400 (16")
• Design Standard: EN 593
• Factory Test: EN 12266 / API 598
• Actuator Interface: ISO 5211

Fluids Compatible with PTFE Liner

• ✅ Sulfuric acid H₂SO₄ up to 30% (room temperature)
• ✅ Hydrochloric acid HCl up to 35%
• ✅ Nitric acid HNO₃ up to 30%
• ✅ Phosphoric acid H₃PO₄ up to 85%
• ✅ Acetic acid up to 80%
• ✅ Caustic soda NaOH up to 50%
• ✅ Sodium hypochlorite NaClO up to 15%
• ✅ Ferric chloride FeCl₃ — any concentration
• ✅ Seawater and aggressive saline solutions
• ✅ Lime slurry and water treatment solutions
• ⚠️ Hydrofluoric acid HF — use PFA anti-corrosion ball valve
• ⚠️ H₂SO₄ >70% — use PFA anti-corrosion ball valve
• ⚠️ ClO₂ in bleaching concentrations — use PFA anti-corrosion ball valve
• ⚠️ Hydrogen peroxide H₂O₂ >30% — use PFA anti-corrosion ball valve

Doubts about compatibility with your specific fluid? Contact us — we'll check for free.

Advantages over Standard Iron Butterfly Valve

• No body metal in contact with the corrosive fluid — the PTFE liner is the only barrier
• Significantly longer service life in fluids that would attack iron or stainless steel
• Lower cost per diameter than the anti-corrosion ball valve in DN150 and above
• Compact wafer installation without a self-contained body — same ease of installation as a standard butterfly valve

Available Operation Versions

• Manual with lever: DN50 to DN150
• Manual with gear reducer: DN200 to DN400
• With pneumatic actuator: Single-acting NC or NO, double-acting. NAMUR solenoid directly on the actuator.
• With electric actuator: 24 VDC, 110 VAC, 220 VAC. ON/OFF or 4–20 mA modulating.

For more information, see the corrosion-resistant butterfly valves category →