Seals are a key element in many industries, from automotive to chemical plants and food processing. The right choice of gasket can mean the difference between a successful and problematic application.
In this article we will look at the different types of gaskets by material, their properties and what to look out for when choosing them.
NBR, also known as nitrile rubber, is one of the most widely used materials for seals, mainly due to its excellent resistance to oils, fuels and other petroleum products.
- Resistance to: fuels, mineral, vegetable and animal oils, water.
- Cons: Not resistant to strong acids, ozone, weather and glycol brake fluids.
- Use: Automotive, hydraulic systems, industrial equipment.
- Temperature range: -30 °C to +120 °C.
NBR seals are often the first choice for applications where contact with oils and fuels is unavoidable, but it is important to note its limited resistance to ozone and weathering.
FPM, also known as Viton, is a fluorocarbon rubber that is highly resistant to chemicals, heat and aggressive substances.
- Resistance to: oils, fuels, solvents, acids.
- Disadvantages: Not resistant to esters, ketones, alcohols and some strongly reducing chemicals.
- Use: Chemical and petrochemical industries, automotive and aerospace.
- Temperature range: -20 °C to +200 °C.
FPM seals are ideal for high temperature and chemical load environments, but should avoid applications where ketones or alcohols are present.
EPDM is a material known for its excellent resistance to ozone, weathering and temperature extremes.
- Resistance to: ozone, weather, water, water vapor, some acids and bases.
- Disadvantages: not resistant to petroleum products and hydrocarbons.
- Use: Automotive, construction, water industry.
- Temperature range: -40 °C to +120 °C (up to +150 °C in some variants).
EPDM seals are often used where weathering and ageing resistance is important, for example in the automotive and construction industries.
Silicone gaskets are known for their wide range of applications, especially for their resistance to temperature fluctuations and flexibility.
- Resistance to: animal and vegetable fats, hydraulic oils, glycol, oxygen, ageing.
- Disadvantages: not resistant to fuels, vapours and some chemicals.
- Use: Food and pharmaceutical industries, electrical insulation.
- Temperature range: -50 °C to +200 °C.
MVQ seals are ideal for applications where thermal stability and resistance to ageing are key, which is important for example in the food industry.
PTFE, also known as Teflon, is one of the most durable gasket materials, particularly due to its resistance to a wide range of chemicals and extreme temperatures.
- Resistance: chemicals, solvents, high temperatures.
- Disadvantages: not resistant to strong alkalis and fluorinated substances.
- Use: Chemical industry, medical applications, food processing.
- Temperature range: -200 °C to +260 °C.
PTFE gaskets are a great choice for demanding chemical and heat-intensive applications, but their cost can be higher than other materials.
Polyurethane gaskets are known for their excellent abrasion resistance and resistance to some chemicals.
- Resistance to: gasoline, diesel, propane, butane, mineral and silicone oils, aging, water up to 50 °C.
- Disadvantages: not resistant to ketones, esters, ethers, alcohols, alkalis, amines, acids and moisture.
- Use: Hydraulic systems, mechanical engineering, automotive.
- Temperature range: -30 °C to +80 °C.
Polyurethane seals are ideal for applications where high abrasion resistance is required, such as hydraulic systems and engineering applications.
The correct choice of seal material depends on many factors, including temperature range, chemical resistance and mechanical stress. Each material has its advantages and limitations, so it is important to carefully consider the requirements of the specific application to ensure an effective and long-lasting seal.
If you are unsure what type of seal is best suited for your application, consulting with experts or seal suppliers can help you select the optimal solution for your needs.