EPDM Ethylene Propylene Diene Monomer SIL Silicone WRAS Certified Rubber Sealing Ring O-Ring
Suzhou Yongxin Technology Co., Ltd. is a supplier of sealing components in motion and control systems, providing sealing solutions for transmission control, automation equipment, and aviation. It sells various seals, hydraulic, pneumatic, and fluid control products and components. In terms of seals, Yongxin offers hydraulic and pneumatic sealing products, including dynamic seals, static seals, sealing rings, oil seals, gaskets, packing, and more.

Ethylene Propylene Diene Monomer (EPDM) is a terpolymer of ethylene, propylene, and a non-conjugated diene. The main characteristics of EPDM are its superior resistance to oxidation, ozone, and erosion. As EPDM belongs to the polyolefin family, it exhibits excellent chemical resistance. Among all rubbers, EPDM has a low specific gravity. It can absorb large amounts of fillers and oils without significantly affecting its properties, making it suitable for producing low-cost rubber compounds. EPDM features outstanding aging resistance, electrical insulation, and ozone resistance. Ethylene propylene rubber can be heavily oil-extended and filled with carbon black, resulting in lower product costs. It has good chemical stability, and its abrasion resistance, elasticity, and oil resistance are comparable to those of styrene-butadiene rubber.
Ethylene propylene rubber is widely used in tire sidewalls, sealing strips, inner tubes, and automotive components.
1. Aging Resistance: EPDM has excellent resistance to weather, ozone, heat, acids, alkalis, steam, color stability, electrical properties, oil extension, and fluidity at room temperature. EPDM products can be used long-term at 120°C and briefly or intermittently at 150-200°C. Suitable anti-aging agents can further improve its temperature resistance. Peroxide-crosslinked EPDM can be used under harsh conditions. EPDM can withstand over 150 hours without cracking under 50 pphm ozone concentration and 30% elongation.
2. Corrosion Resistance Rating Volume Swelling Rate/% Hardness Reduction Impact on Performance 1 lt;10<10 Slight or none. 2. 10-20<20 Minor 3. 30-60<30 Moderate. 4 gt;60>30 Severe
3. Steam Resistance: EPDM has excellent steam resistance, even surpassing its heat resistance. After nearly 100 hours in superheated steam at 230°C, its appearance remains unchanged. In contrast, fluororubber, silicone rubber, fluorosilicone rubber, butyl rubber, nitrile rubber, and natural rubber show significant deterioration in appearance under the same conditions in a shorter time.
4. Hot Water Resistance: EPDM also performs well in resistance to hot water, but this is closely related to the vulcanization system. EPDM vulcanized with dicumyl peroxide and TMTD shows minimal change in mechanical properties after 15 months of immersion in superheated water at 125°C, with a volume swelling rate of only 0.3%.
5. Electrical Properties: EPDM has excellent electrical insulation and corona resistance, outperforming styrene-butadiene rubber, chlorosulfonated polyethylene, polyethylene, and crosslinked polyethylene.
6. Elasticity: Due to the absence of polar substituents in its molecular structure and low cohesive energy, EPDM maintains flexibility over a wide range, second only to natural rubber and polybutadiene rubber, and remains flexible at low temperatures.
7. Adhesion: EPDM lacks active groups in its molecular structure, has low cohesive energy, and is prone to blooming, resulting in poor self-adhesion and mutual adhesion.
Compared to other types of sealing rings, O-rings offer the following advantages:
- Suitable for multiple sealing forms: static sealing, dynamic sealing
- Suitable for various applications, with standardized materials, sizes, and grooves, ensuring strong interchangeability
- Suitable for multiple motion types: rotational motion, axial reciprocating motion, or combined motion (e.g., rotational reciprocating motion)
- Suitable for various sealing media: oil, water, gas, chemical media, or other mixed media
By selecting appropriate rubber materials and配方 designs, effective sealing for oil, water, air, gas, and various chemical media can be achieved. The temperature range is wide (-60°C to +220°C), and when used in fixed applications, pressure can reach up to 1500 kg/cm2 (when used with reinforcing rings).
- Simple design, compact structure, easy installation and removal

The O-ring has a simple cross-sectional structure and self-sealing action, ensuring reliable sealing performance.
Due to the simplicity of the O-ring itself and its installation parts, and its standardization, installation and replacement are very easy.
- Wide variety of materials
Selection can be made based on different fluids: nitrile rubber (NBR), fluororubber (FKM), silicone rubber (VMQ), ethylene propylene rubber (EPDM), chloroprene rubber (CR), butyl rubber (BU), polytetrafluoroethylene (PTFE), natural rubber (NR), etc.
- Low cost
- Low dynamic friction resistance
EPDM Ethylene Propylene Diene Monomer Rubber Sealing Ring
Offers excellent weather resistance, ozone resistance, water resistance, and chemical resistance. Suitable for use with alcohols and ketones, as well as for sealing in high-temperature steam environments. Applicable in sanitary equipment, automotive radiators, and automotive braking systems. Not recommended for food applications or use in mineral oils. General temperature range: -55°C to 150°C.
FLS Fluorosilicone Rubber Sealing Ring
Combines the advantages of fluororubber and silicone rubber, with excellent resistance to oil, solvents, fuel, and high and low temperatures. Resistant to oxygenated compounds, aromatic solvents, and chlorinated solvents. Generally used in aviation, aerospace, and military applications. Not recommended for use with ketones and brake fluids. General temperature range: -50°C to 200°C.