What types of sealing materials are there?

Aramid fiber gaskets are NBR-bonded (e.g. KlingerSil® C-4400) and asbestos-free. They offer good resistance to aging, pressure, and temperature, with a range of -100 °C to 175 °C and working pressures up to 60 bar. Aramid fiber gaskets are resistant to steam, hot water, various gases, fuels, lubricants, as well as organic and inorganic acids.

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Pure graphite gaskets are made from expanded graphite and offer excellent resistance to extreme temperatures (from -200 °C to 550 °C) and chemicals, including saturated steam, gases, fuels, acids, and alkalis. They are also highly pressure-resistant and suitable for demanding industrial applications where reliable sealing is essential.

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EPDM (Ethylene Propylene Diene Monomer) is an elastomer with high resistance to water, glycols, brake fluids, acids, and alkalis. These gaskets are temperature-resistant from -50 °C to 130 °C and withstand pressures up to 16 bar, depending on the medium – and in certain applications even up to 50 bar. However, EPDM is not suitable for applications with mineral oils, fuels, and non-polar solvents.

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NBR (nitrile butadiene rubber) is an elastomer offering high resistance to mineral oils, fats, fuels, and waxes, but not to concentrated acids or certain chemicals. NBR gaskets are suitable for temperatures from -30 °C to 100 °C and withstand pressures up to 16 bar – or up to 50 bar in specific applications. They are ideal for applications in the oil and fuel industry.

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FFKM (Perfluoroelastomer) seals are characterized by their excellent chemical resistance and suitability for extreme temperatures ranging from -25 °C to 325 °C. They provide outstanding resistance to a variety of chemicals, including mineral oils, fuels, amines, and moderate acids. FFKM is ideal for demanding applications in industry where high resistance and durability are required.

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Phlogopite mica gaskets are suitable for extreme thermal applications, with a working temperature of -200 to 1000 °C and a working pressure of up to 60 bar. They are chemically resistant and are excellent for sealing in high-temperature environments such as furnace flue gases. Phlogopite mica offers high aging resistance and is particularly resilient to aggressive media.

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FKM (Fluoroelastomer) is a durable elastomer that is resistant to high temperatures (from -20 °C to 200 °C) and numerous chemicals such as mineral oils, fuels, and moderate acids. It offers high aging and pressure resistance but is not suitable for highly concentrated acids or oxidizing media.

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PTFE (Polytetrafluorethylen) is versatile due to its chemical resistance and temperature resistance from -100 °C to 250 °C. It is resistant to almost all media, except for strong alkaline metals and fluorine under high pressure. PTFE gaskets are particularly suitable for applications that have high requirements for resistance and purity.

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These gaskets are made of expanded graphite with impregnations and metal reinforcements and offer high resistance to temperatures from -200 °C to 550 °C as well as pressures up to 250 bar. They are particularly resistant to saturated steam, gases, salts, fuels, and numerous chemicals. These properties make them ideal for use under extreme conditions in industrial applications.

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Silicone (vinyl methyl silicone rubber) is an elastomer that is used in a wide temperature range from -60 °C to 180 °C. It offers medium resistance to aging and is resistant to mineral oils, animal and vegetable fats, as well as some essential oils. However, silicone is unsuitable for concentrated acids and oxidizing media, which is why it is only used for specific applications in sealing technology.

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