High-Temperature Silicone

High-Temperature Silicone Seals & Gaskets: What OEM Buyers Need to Know

When industrial equipment, ovens, exhaust systems, or continuous high-heat processes require reliable sealing, standard silicone often reaches its limit. Continuous service above 200 °C demands specialized high-temperature silicone compounds. Choosing the wrong grade can lead to rapid compression set, hardening, cracking, or complete loss of sealing force.

Key Temperature Performance Facts

Standard silicone typically operates continuously from –60 °C to +200 °C. For continuous exposure above 200 °C, high-temperature formulations are required. Some grades can handle intermittent peaks up to 300 °C, but continuous service above 230–250 °C significantly shortens life if the wrong compound is selected.

The most critical long-term performance metric is not hardness alone, but compression set at elevated temperature. A gasket that seals perfectly on day one may leak after a few thermal cycles if compression set exceeds 20–25 %.

Practical Specification Tips for OEM Projects

• Clearly distinguish continuous temperature from intermittent peak temperature

• Specify the required compression set (e.g., <20 % after 22 h at 175 °C or 200 °C)

• Indicate whether the joint experiences thermal cycling or remains under constant compression

• Consider fluorosilicone (FVMQ) if the seal also contacts oils, fuels, or solvents

When High-Temperature Silicone Is the Right Choice

High-temperature silicone is preferred for oven seals, industrial equipment gaskets, exhaust-adjacent applications, and any continuous service above 200 °C where flexibility and sealing force retention are critical. For extreme chemical exposure combined with heat, fluorosilicone or alternative elastomers may be necessary.

Working with a high temperature silicone seals manufacturer that can formulate or select the correct compound — and provide real compression-set data — reduces the risk of premature field failures.