Silicone vs. FKM (Viton) for Extreme Seals: Thermal, Chemical & Mechanical Reality

When designing custom molded seals, extruded tubing, or high-performance gaskets, choosing between Silicone and FKM (Fluorocarbon / Viton®) often determines whether your seal handles continuous duty or suffers premature degradation.

While both are high-tier elastomers, they solve entirely different chemical and mechanical problems. Using Silicone where FKM is needed leads to fluid swelling and chemical attack; using FKM where Silicone is ideal adds unnecessary material cost and limits extreme low-temperature flexibility.

Below is an engineering selection guide from Hangzhou LINGO Rubber and Plastic:

 Quick Technical Comparison

 Engineering Selection Framework

Choose Silicone (VMQ / Liquid Silicone) if:

• Extreme Cold/Heat Cycles: Your application operates in cryogenic or low-temperature outdoor environments down to -60°C.

• Food, Medical & Appliance Cleanliness: You require non-reactive, odorless, food-grade seals for medical devices, food processing machinery, or domestic appliances.

• Low Compression Force: The mating housing requires a soft, highly flexible gasket to seal against delicate glass, plastic, or light metal frames.

Choose FKM (Viton®) if:

• Aggressive Hydrocarbon Contact: The seal is directly exposed to automotive fuels, synthetic oils, transmission fluids, or aggressive petrochemicals.

• High-Pressure Dynamic Sealing: You need high tensile strength and tear resistance for hydraulic shafts, fuel injection systems, or dynamic rotary seals.

• Severe Industrial Vacuum: Your equipment requires low outgassing under high vacuum and elevated temperatures.

 Precision Manufacturing at Hangzhou LINGO

Whether your project requires custom extruded silicone profiles or high-precision FKM molded seals, Hangzhou LINGO Rubber and Plastic provides end-to-end quality control:

• Silicone Processing: Continuous platinum-cured profile extrusion, liquid silicone rubber (LSR) molding, and food-grade tubing.

• FKM Processing: Precision compression and injection molding for high-spec O-rings, valve seats, and custom industrial gaskets.

Located near Shanghai and Ningbo Ports, we support global Tier-1 OEMs with rapid DFM reviews, quick prototyping, and secure international logistics.

Working on a challenging seal design or comparing compound specifications? Please send us your engineering drawings and we will provide you with assistance！