Description
Fluorine Lined Check Valves (also known as PTFE/PFA lined non-return valves or chemical check valves) are critical safety components engineered to prevent reverse flow and media backsiphonage in highly aggressive chemical pipelines. Featuring a seamless virgin fluoroplastic lining and acid-resistant internal discs or balls, these check valves deliver instant, automatic uni-directional seal performance in harsh acid, alkali, and organic solvent processes.
Designed for severe backflow prevention, these lined non-return valves work seamlessly alongside our industrial butterfly valves and integrate directly into fluoroplastic piping loops using precision-forged industrial flanges.
Technical Specifications
| Technical Parameter | Specification Details |
|---|---|
| Nominal Diameter Range | DN15 to DN600 (1/2" to 24") |
| Nominal Pressure | PN10 / PN16 / Class 150 |
| Outer Body Material | Ductile Iron (QT450-10), WCB (Carbon Steel), Stainless Steel (CF8 / 304 SS) |
| Lining Material Options | PTFE (Polytetrafluoroethylene) / PFA (Perfluoroalkoxy) / FEP (F46) |
| Structure Design | Swing Type / Ball Type (Free-floating) / Lift Type / Wafer Type |
| Working Temperature | -20°C to 180°C (-4°F to 356°F) |
| Connection Standard | Flanged Ends (ASME B16.5 Class 150, HG/T 20592, EN 1092-1) / Wafer Connection |
| Testing & Inspection | 100% Spark Test (15kV-25kV) & Shell/Seat Hydrostatic Test |
Key Features & Anti-Backflow Mechanics
Preventing hazardous chemical backflow requires robust mechanical seating and universal fluoroplastic protection:
- Full Chemical Inertness: Virgin PTFE/PFA/FEP lining covers all internal metallic surfaces and fluid-wetted areas, resisting all concentrations of hydrochloric, sulfuric, and nitric acids.
- Instant Fast Response & Low Cracking Pressure: Streamlined inner disc/ball geometries ensure sensitive opening under low cracking pressure and immediate, tight closing upon backpressure or flow reversal.
- Vacuum & Permeation Resistant Molding: Mechanical locking grooves cast into the outer metallic shell lock the fluoroplastic lining securely in place, preventing lining collapse under vacuum conditions.
Target Applications & Industries
Our fluorine-lined check valves are installed across critical chemical loop protection zones:
- Chemical Processing & Chlor-Alkali: Acid circulation pumps discharge, chlorine gas, and reactor feed line safety.
- Pharmaceuticals & Fine Chemicals: Corrosive solvent recovery, high-purity chemical transfer, and fluid separation lines.
- Steel Pickling & Waste Treatment: Spent acid regeneration, pickling liquor pumping, and hazardous effluent processing.
Frequently Asked Questions (FAQ)
Q1: How do I select between swing type and ball type fluorine-lined check valves?
Choose swing check valves for horizontal piping with larger flow diameters and lower pressure drop. Choose ball check valves (free-floating PTFE ball) for vertical upward flows or viscous fluids requiring self-cleaning closure.
Q2: How is the lining quality verified prior to shipment?
Every fluorine-lined check valve undergoes a 15kV–25kV high-voltage spark test to ensure zero pinholes or lining flaws, followed by strict seat seal pressure testing.
Q3: Can Oucang Valve supply spring-loaded fluorine-lined check valves?
Yes. As a direct factory, Oucang Valve can customize spring-assisted lift or wafer check valves with Hastelloy or PTFE-coated springs for rapid closing in pulsating pump systems.
About the Manufacturer: Oucang Valve
Oucang Valve is an ISO-certified direct manufacturer specializing in fluoroplastic-lined valves, non-return valves, and forged industrial pipe flanges. Operating our own foundry, PTFE/PFA molding workshop, and pressure testing laboratory, we deliver full material certification and custom engineering for global chemical projects.
- Core Capability: Precision PFA/PTFE lining injection, high-voltage spark testing, custom check valve fabrication, and rapid direct export.
- Quality Compliance: ASME B16.5, HG/T 21562, EN, DIN, and ISO standards.
- Factory Inquiry: Contact our engineering sales team for direct factory quotations, chemical resistance charts, and 2D/3D CAD drawings.
