Direct Answer

Rubber lined butterfly valves use elastomer linings (such as EPDM or NBR) for cost-effective sealing in water and mild service, while PTFE butterfly valves use polytetrafluoroethylene lining for superior chemical resistance and wider temperature compatibility in corrosive industrial applications. The key difference is chemical resistance versus cost efficiency.

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Sealing Material Difference

Rubber Lined Butterfly Valve

Rubber lined valves use elastic materials such as:

• EPDM
• NBR (Buna-N)
• Natural rubber

These materials provide flexible sealing and good elasticity.

Key characteristics:

• Tight shutoff in water service
• Good elasticity and recovery
• Lower cost
• Limited chemical resistance

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PTFE Butterfly Valve

PTFE (Teflon) lining provides a chemically inert sealing surface.

Key characteristics:

• Excellent chemical resistance
• Low friction surface
• Suitable for aggressive media
• More rigid than rubber seats

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Chemical Resistance

Rubber Lined

• Suitable for clean water
• Mild acids and alkalis
• HVAC and utility systems
• Not suitable for strong solvents or aggressive chemicals

PTFE Lined

• Strong acids
• Strong alkalis
• Solvents and corrosive chemicals
• Chemical processing industries

PTFE clearly outperforms rubber in harsh chemical environments.

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Temperature Performance

Rubber Lined

• Typically -20°C to 120°C (up to 150°C for special compounds)
• Performance decreases at high temperature

PTFE

• Typically -20°C to 180–200°C
• Better stability at elevated temperatures
• Suitable for wider process conditions

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Durability and Wear Resistance

Rubber Lined

• Good elasticity but wears faster under abrasion
• Can deform under high pressure or temperature
• Requires periodic replacement in harsh service

PTFE

• Excellent wear resistance against chemicals
• Low friction reduces mechanical wear
• Longer service life in corrosive systems

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Cost Comparison

Rubber Lined

• Lower cost
• Economical for water systems
• Widely used in municipal projects

PTFE Lined

• Higher cost
• Premium material for chemical applications
• Better long-term value in corrosive service

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Pressure Capability

Rubber Lined

• Low to medium pressure (PN10–PN16 / Class 150)
• Limited by elastomer strength

PTFE

• Medium pressure capability
• Better stability under chemical and thermal stress
• Often used in process industries

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Applications

Rubber Lined Butterfly Valve Applications

• Water treatment plants
• HVAC systems
• Fire protection
• Irrigation systems
• General industrial utilities

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PTFE Butterfly Valve Applications

• Chemical processing plants
• Pharmaceutical industry
• Acid and solvent pipelines
• Petrochemical systems
• Aggressive fluid handling systems

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When to Choose Each Type

Choose Rubber Lined Butterfly Valve if you need:

• Low cost solution
• Clean water service
• HVAC or utility systems
• General industrial applications

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Choose PTFE Butterfly Valve if you need:

• Strong chemical resistance
• High corrosion protection
• Aggressive fluid handling
• Longer service life in harsh environments

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Conclusion

Rubber lined butterfly valves are ideal for economical water and utility applications, while PTFE butterfly valves are designed for chemical resistance and harsh industrial environments. The best choice depends on whether cost efficiency or chemical performance is the priority.

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Frequently Asked Questions

Is PTFE better than rubber lining in butterfly valves?

Yes, PTFE performs better in chemical resistance and temperature stability, but rubber lining is more cost-effective for water systems.

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Can rubber lined butterfly valves be used for chemicals?

Only for mild chemicals. Strong acids, solvents, and aggressive media require PTFE-lined valves.

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Why are PTFE butterfly valves more expensive?

Because PTFE material offers higher chemical resistance, longer service life, and more complex manufacturing compared to rubber linings.