Valves lined with PFA, FEP, PP, PVDF, and PTFE are essential in industries that handle corrosive, aggressive, or high-purity fluids. These lined valves extend equipment life, reduce maintenance costs, and ensure safety in chemical processing, pharmaceuticals, food and beverage, oil and gas, and water treatment industries.
This guide covers everything about ball check valves, butterfly valves, diaphragm valves, plug valves, and PTFE lined plug valves made from PFA, FEP, PP, PVDF, and PTFE.
What are Lined Valves?
Lined valves are standard industrial valves internally coated with fluoropolymers like PFA (Perfluoroalkoxy), FEP (Fluorinated Ethylene Propylene), PTFE (Polytetrafluoroethylene), or thermoplastics such as PP (Polypropylene) and PVDF (Polyvinylidene Fluoride).
These linings:
- Provide excellent chemical resistance
- Allow operation in high-temperature and high-pressure environments
- Prevent metal body corrosion
- Extend service life in acidic, alkaline, and solvent-based media
Types of Lined Valves
1. PFA/FEP Ball Check Valves
2. Ball check valves are non-return valves that allow flow in one direction and prevent reverse flow. When lined with PFA or FEP, they can handle highly corrosive chemicals safely.
Key features:
- PFA ball check valve and FEP ball check valve for aggressive chemicals
- Self-cleaning and low-maintenance design
- Ideal for corrosive slurries, acids, and solvents
- Resistant to scaling and contamination
Applications:
- Chemical dosing
- Wastewater treatment
- Pharmaceuticals
- Acid and alkali transfer
PFA/FEP Butterfly Valves:-
Butterfly valves are compact, lightweight, and ideal for quick shut-off in pipelines. When lined with PFA or FEP, they become highly durable against corrosive fluids.
Key features:
- PFA butterfly valve and FEP butterfly valve with corrosion resistance
- Low torque operation
- Available in wafer and lug designs
- High-performance and double-offset options
Applications:
- Chemical transfer systems
- HVAC pipelines
- Water and wastewater industries
- Oil and gas
PFA/FEP Diaphragm Valves:-
Diaphragm valves control flow using a flexible diaphragm that ensures bubble-tight shutoff. PFA/FEP linings provide protection against abrasive and aggressive media.
Key features:
- Leak-proof sealing
- Resistant to scaling
- Easy maintenance
- Suitable for cleanroom and sterile applications
Applications:
- Biotech and pharma
- Chemical processing
- Food and beverage
- High-purity water systems
PFA/FEP Plug Valves:-
Plug valves offer smooth shut-off and throttling functions. Lined with PFA or FEP, they provide reliable performance in acidic and solvent-based systems.
Key features:
- Non-lubricated plug design
- PFA plug valve and FEP plug valve for chemical safety
- High temperature and pressure resistance
- Long service life with reduced wear
Applications:
- Acid transfer lines
- Petrochemicals
- Solvent distribution
- Corrosive chemical pipelines
PP/PVDF Valves:-
PP (Polypropylene) and PVDF (Polyvinylidene Fluoride) valves are cost-effective solutions for handling moderately corrosive fluids.
Key features:
- Lightweight and easy to install
- High resistance to alkalis, acids, and organic solvents
- Available as ball valves, diaphragm valves, and plug valves
- Economical alternative to metal valves
Applications:
- Water treatment plants
- Chemical industries
- Electroplating units
- Wastewater treatment
PTFE Lined Plug Valves
- PTFE lined plug valves are the ultimate choice for zero leakage and long-term durability in the harshest environments.
Key features:
- Excellent resistance to all chemicals
- Non-stick surface prevents scaling and deposits
- Long operational life with minimal maintenance
- Designed for high purity and aggressive services
Applications:
- Fertilizer plants
- Oil and gas
- Acid and solvent transfer
- Pharmaceutical processing.
- Advantages of PFA, FEP, PP, PVDF, and PTFE Lined Valves
- Maximum corrosion resistance
- Extended service life
- Low maintenance costs
- Versatility across industries
- Reliable sealing with leak-proof performance
- Compatibility with high-temperature and aggressive fluids
What is the difference between PFA and FEP valves?
A: PFA has higher mechanical strength and higher temperature tolerance, while FEP is more flexible and cost-effective.
Why choose PTFE lined plug valves over PFA plug valves?
A: PTFE provides the broadest chemical resistance and ensures longer service life in extreme corrosive conditions.
Are PP and PVDF valves suitable for chemical plants?
A: Yes, PP valves are cost-effective for moderate corrosives, while PVDF valves offer higher resistance to aggressive chemicals.
Which valve is best for acid transfer?
A: PTFE lined plug valves and PFA ball check valves are preferred for strong acids due to their chemical inertness.
How do PFA lined diaphragm valves work?
A: They use a flexible diaphragm to control flow and provide leak-proof shutoff in chemical and pharmaceutical processes.
Where are PFA/FEP butterfly valves commonly used?
A: They are widely used in pipelines for chemical processing, HVAC, water treatment, and oil and gas industries.
Buying Guide: Choosing the Right Lined Valve
When selecting a lined valve, consider:-
Type of fluid (acid, alkali, solvent, slurry)
- Pressure and temperature conditions
- Flow control requirement (on/off vs throttling)
- Valve type (ball check, butterfly, diaphragm, plug)
- Lining material (PFA, FEP, PTFE, PP, PVDF)
- Maintenance and lifecycle cost
Conclusion:-
PFA, FEP, PP, PVDF, and PTFE lined valves are indispensable in modern industries. Each type—ball check valves, butterfly valves, diaphragm valves, plug valves, and PTFE lined plug valves—delivers specific benefits for handling corrosive, aggressive, or high-purity media.
For reliable, durable, and corrosion-resistant lined valves, Sandogroup offers a complete range that ensures safety, performance, and long-term efficiency in demanding applications.
Sando Editorial Team
Pump technology experts at Sando Rotary Equipments