Product Introduction:
The encapsulated seal ring (PTFE encapsulated ring) organically combines the elasticity and sealing properties of rubber with the chemical resistance of Teflon. It consists of one or more inner cores made of Viton rubber (fluororubber) and a relatively thin outer layer of Teflon FEP (fluorinated ethylene propylene) or Teflon PFA (perfluoroalkoxy). This rubber-Teflon seal ring offers excellent sealing performance. Rubber O-rings are prone to wear, have poor chemical corrosion resistance, and exhibit weak gas permeability resistance. Pure O-rings have higher hardness and can resist compression but lack elasticity. The outer layer of Teflon FEP/Teflon PFA O-rings provides excellent resistance to swelling and chemical stability (unless attacked by alkali metals, fluorine, and some halides at high temperatures). They maintain good elasticity near the rubber O-ring area, with a very low friction coefficient (only 0.1~0.2) and excellent gas permeability resistance. These properties make encapsulated seal rings suitable for harsh environments. Therefore, PTFE encapsulated O-rings can replace expensive rubber O-rings.

Teflon Seal Ring: The Secret Weapon for High Temperature and High Pressure
Have you ever heard of TEFLON RING?

It is essentially a polytetrafluoroethylene (PTFE, also known as Teflon) seal ring. This type of seal ring has a Teflon coating on the outer surface of the O-ring, combining the elasticity of rubber with the chemical resistance and low friction characteristics of Teflon. It is tailor-made for applications requiring chemical corrosion resistance, high temperature resistance, or extreme pressure tolerance.

The benefits of the Teflon coating go beyond that. During installation, it helps reduce friction, making the O-ring easier to install. Moreover, Teflon's durability enhances the service life of the O-ring. Whether in high-temperature, high-pressure, or highly corrosive environments, this seal ring performs stably.

Main Features:
1. Outstanding chemical resistance, suitable for almost all chemical media

2. Excellent corrosion resistance

3. Wide temperature application range

4. Good compression resistance

5. Anti-friction

6. Good swelling resistance

7. High-pressure resistance

8. Long-lasting sealing performance and extended service life

Function:
The seamless and uniformly dense outer layer of Teflon FEP/Teflon PFA, combined with the rubber inner core, ensures consistent sealing performance of the encapsulated seal ring. The elasticity and compression are uniform at every point of the seal ring, allowing repeated installation and use under continuous pressure. As the medium pressure increases, the entire seal ring is compressed. The encapsulated seal ring acts like a high-viscosity liquid, transmitting the applied pressure undiminished in all directions.

Structural Description:
The encapsulated O-ring combines the chemical resistance of PTFE with the elasticity of rubber. It consists of an outer plastic layer encapsulating an inner rubber core, making it resistant to almost all chemical media (except soluble alkali metals, high-temperature fluorine gas, and certain halides). It is primarily used in pumps and valves, heat exchangers, boilers, filters, reaction vessels, pressure vessels, pipeline flanges, mechanical seals, gas compressors, extraction equipment, etc.

Three types of outer plastic layers:
1. (FEP) Fluorinated ethylene propylene, temperature range -20°C to 200°C, general-purpose type;
2. (PFA) Perfluoroalkoxy, temperature range -20°C to 260°C, high-temperature resistant type;
3. Double-layer PTFE, resistant to high and low temperatures, -50°C to 260°C, for special corrosion applications;

Two main types of inner rubber:
1. Silicone rubber (SIL)
2. Fluororubber (FKM)
Others such as nitrile rubber (NBR) and ethylene propylene diene monomer (EPDM) require customization.

Compression Resistance:
The presence of the FEP outer layer gives the encapsulated seal ring excellent resistance to hardening and brittleness. Meanwhile, the inner core made of silicone rubber or Viton rubber ensures that the seal ring maintains good elasticity even at high temperatures of 205°C.