Key Differences Between EPDM and PTFE Sealed Butterfly Valves

When many users choose soft seal butterfly valves, the first reaction is often to look at the size, pressure rating and connection mode, but in practical use, it is often an easily ignored detail 'seat material' that really determines the service life, sealing reliability and working condition adaptability of the valve.

The sealing principle of soft sealing butterfly valve relies on the interference compression of valve plate and elastic seat to achieve zero leakage.

The butterfly valve seat material is different, and its performance gap is very obvious, the choice of sealing material directly affects their performance, service life and application scope.

This article focuses on the key differences between EPDM butterfly valve and PTFE sealed butterfly valves to help customers make more suitable choices for different working conditions.

EPDM butterfly valve, EPDM (Ethylene Propylene Diene Monomer) is a soft rubber sealing material, featuring excellent elasticity and tight sealing performance, which can achieve zero leakage in normal working conditions. It is suitable for water systems such as tap water, sewage and circulating water, as well as HVAC and cooling water systems. The operating temperature range of EPDM seals is -20℃ to 120℃, and it has good resistance to water, steam and weak acids and alkalis, but it is not resistant to oil, making it not suitable for oily media.

PTFE butterfly valve, PTFE (Polytetrafluoroethylene), known as the 'king of plastics', is a hard semi-hard sealing material with outstanding high temperature resistance (operating temperature -20℃ to 200℃) and corrosion resistance, which can resist almost all acids, alkalis and solvents. It has good wear resistance and self-lubrication, with a longer service life than EPDM. PTFE seat butterfly valves are widely used in harsh working conditions such as chemical industry, petroleum, pharmaceutical and food industries, especially for corrosive and high-temperature media.

In terms of cost, EPDM sealed butterfly valves are more economical and suitable for general normal temperature and non-corrosive working conditions, while PTFE sealed ones are slightly more expensive but more reliable for high-end harsh environments. Choosing the right sealing material can effectively improve the operation efficiency of the system and reduce maintenance costs.