Nitrile Rubber (NBR) is a cost-effective synthetic rubber widely adopted in general industrial scenarios. It is copolymerized from butadiene and acrylonitrile, boasting excellent oil resistance, wear resistance and airtightness, which makes it ideal for sealing oil-based media. NBR flat gaskets operate stably within a temperature range of -20℃ to 110℃ and a pressure of up to 16MPa, and are extensively applied in automotive engines, hydraulic systems, industrial machinery and oil pipelines. However, their resistance to ozone and weathering is relatively weak, limiting their use in outdoor or strong oxidizing environments.
Silicone (Sil) gaskets stand out for their exceptional resistance to extreme temperatures, maintaining elasticity and sealing performance between -100℃ and 300℃. They feature biocompatibility, non-toxicity and low volatility, making them the first choice for medical devices, food processing equipment and new energy vehicle (NEV) battery packs. Additionally, silicone's excellent ozone and aging resistance enables its application in electronic equipment and high-temperature mechanical sealing. The main drawback is its poor oil resistance, which restricts use in oil-rich environments.
EPDM (Ethylene Propylene Diene Monomer) is a synthetic rubber with superior weather resistance, chemical stability and electrical insulation. It can withstand temperatures from -57℃ to 176℃ and is highly resistant to ozone, sunlight, moisture and most acids and alkalis. EPDM flat gaskets dominate in construction, photovoltaic power generation, water treatment and electrical equipment fields-for instance, they are widely used in solar panel sealing and building waterproofing systems. Their low compatibility with oil and hydrocarbon media, however, excludes them from oil-based application scenarios.
PTFE (Polytetrafluoroethylene) gaskets are renowned for their "non-stick" properties and universal chemical resistance, being inert to almost all corrosive media such as strong acids, alkalis and oxidants. Modified by nano-technology, PTFE gaskets now have enhanced dynamic sealing performance, expanding their application in high-pressure hydrogen storage systems, semiconductor vacuum equipment and chemical reactors. They work well at -200℃ to 260℃ but have relatively low mechanical strength, often requiring composite reinforcement with other materials for high-pressure scenarios.
Fluororubber (FKM) is a high-performance material designed for harsh working conditions. It excels in heat resistance (operating temperature: -20℃ to 200℃), oil resistance and chemical corrosion resistance, and can withstand high vacuum and high-pressure environments. FKM flat gaskets are indispensable in aerospace, deep-water oil & gas exploration, semiconductor manufacturing and other high-end fields. Despite their outstanding performance, their high production cost and poor low-temperature flexibility make them unsuitable for low-cost or ultra-low-temperature applications.
In terms of production and selection, custom rubber flat gaskets are manufactured through molding and cutting processes. Molding is cost-effective for mass production, while cutting is suitable for small-batch, customized sizes. Selection should follow core principles: match material characteristics with medium type, temperature and pressure; prioritize environmental adaptability-such as choosing EPDM for outdoor use and silicone for medical scenarios; and avoid inferior reclaimed rubber products, which have unstable performance and potential safety hazards.
With the upgrading of high-end manufacturing, the demand for customized gasket solutions is growing. Material modification, such as hydrogenated NBR (HNBR) which balances oil and heat resistance, and composite materials combining PTFE with rubber, are becoming industry development trends. For enterprises, mastering the characteristics of core materials and adhering to scientific selection and application standards is crucial to improving equipment reliability and reducing operational risks.