Rubber seals and gaskets: types and applications / Articles

Rubber seals and gaskets are indispensable elements of modern equipment and infrastructure, ensuring joint tightness, protection against leaks and ingress of aggressive media. These products are manufactured from various types of rubbers and rubber compounds and are used in virtually all industries: from oil and gas and mechanical engineering to food production and construction. Sealing gaskets are among the most mass-produced rubber technical products, and the reliability and safety of many technical systems directly depend on their quality.

Classification of Seals

By operating principle, seals are divided into two main groups: static and dynamic. Static seals (gaskets, flat rings) are used for sealing fixed joints — pipeline flanges, pump and apparatus housings. Dynamic seals (cuffs, oil seals, O-rings) operate under movement — rotational or reciprocating — ensuring tightness of movable joints.

By design, the following are distinguished:

Flat gaskets — the simplest type, a sheet material cut to the shape of the sealing surface. Used for sealing flanged joints, housing parts, pipelines at low and medium pressures.
O-rings — a universal type of seal, a ring with a circular cross-section. Installed in special grooves and provide sealing for both static and dynamic joints.
Profiled (moulded) seals — products of complex geometry manufactured by moulding. Used for sealing window and door openings, automotive glass, instrument housings.
Cuffs and oil seals — seals for shafts and rods operating under rotational or reciprocating motion.

Main Types of Rubbers for Seals

The choice of material for a seal is determined by operating conditions: temperature, contact medium, pressure and load character.

EPDM (ethylene propylene diene monomer rubber). EPDM is considered the most water-resistant and affordable elastomer currently available. Sealing gaskets from this material class are most often used in cold and hot water supply systems up to 110 °C. EPDM is distinguished by high resistance to ozone, UV radiation, weathering and ageing. The material is suitable for contact with chlorinated water, steam and aqueous solutions of acids and alkalis. The operating temperature range is from -50 to +80 °C (for certain grades — up to +110 °C). The main disadvantage is low resistance to mineral oils and non-polar hydrocarbons.

NBR (nitrile butadiene rubber). NBR is the standard material for seals operating in contact with oils, fuels and fats. Nitrile rubber possesses excellent oil resistance, high mechanical strength and wear resistance. NBR sealing rings are resistant to oils, fats and fuels, retaining flexibility and low-temperature resistance. The operating temperature range is from -30 to +100 °C (for hydrogenated grades HNBR — up to +150 °C). NBR is not recommended for contact with ketones, esters and strong acids.

Silicone rubber (VMQ). Silicone seals possess an exceptionally wide temperature range: from -60 to +200 °C, and for special grades — up to +250 °C. Silicone retains elasticity at low temperatures, is physiologically inert, does not emit harmful substances and is widely used in the food and medical industries. Disadvantages include moderate resistance to oils and solvents. According to GOST 30778-2001, silicone seals (group II) are intended for operation from -60 to +80 °C.

Fluoroelastomer (FKM/Viton). Fluoroelastomers possess the highest chemical resistance among elastomers. They are resistant to oils, fuels, acids, alkalis and solvents. Operating temperature — from -20 to +200 °C, short-term — up to +250 °C. Used in critical components of oil and gas equipment, aviation and automotive technology.

Chloroprene rubber (CR/neoprene). Chloroprene seals combine flame resistance, ozone resistance and moderate oil resistance. Operating temperature range is from -40 to +120 °C. Used in construction, for sealing roofing and waterproofing systems, as well as in the automotive industry.

Natural rubber (NR). Natural rubber possesses high elasticity and strength, but limited resistance to oils and ozone. Used for seals operating in aqueous media and at low temperatures. Often used in blends with other rubbers to improve processing properties.

Properties of Sealing Gaskets

The main characteristics of rubber seals are:

Shore A hardness — typically 40–90 units. Soft gaskets better fill surface irregularities, hard ones withstand higher pressures.
Tensile strength — for most grades, 10–25 MPa.
Elongation at break — 150–500%.
Compression set — a key indicator for assessing seal durability during long-term operation.
Temperature range — determined by the type of rubber.
Resistance to working medium — determined by the chemical nature of the rubber.

Applications

Oil and gas industry. Seals and gaskets made of NBR, HNBR and FKM ensure the tightness of pipelines, pumping systems, compressors and valves. Products operate in contact with hydrocarbons at high pressures and temperatures. For particularly critical components, FFKM elastomers resistant to explosive decompression are used.

Mechanical engineering and automotive industry. Gaskets and seals are used for sealing engines, gearboxes, hydraulic and pneumatic systems. This is the largest consumption segment for moulded and non-moulded seals. Typical applications include cylinder head gaskets, oil pan gaskets, crankshaft and camshaft seals.

Food industry. For contact with food products, silicone and NBR gaskets complying with GOST 17133-83 requirements are used. The standard applies to vulcanised rubber plates for seals of fixed joints in contact with food products at pressures up to 0.6 MPa and temperatures from -30 to +140 °C.

Construction. EPDM seals are widely used for sealing window and door openings, roofing membranes, waterproofing of tunnels and underground structures. Thanks to high resistance to UV radiation and weathering, the service life of such seals reaches 50 years.

Chemical and petrochemical industry. For sealing apparatus operating with aggressive media, gaskets made of FKM and special NBR grades are used. Sheet non-asbestos gasket materials ensure tightness at pressures up to 40 MPa.

Water supply and utilities. EPDM gaskets for cold and hot water supply, sewerage and heating systems. Comply with GOST 19177-81 "Rubber porous sealing gaskets".

Regulatory Framework

In Russia and CIS countries, requirements for rubber seals and gaskets are regulated by a system of state standards:

GOST 30778-2001 — sealing gaskets made of elastomeric materials for window and door blocks. Classifies seals by polymer type into four groups: I — based on EPDM (from -50 to +80 °C), II — based on silicone rubber (from -60 to +80 °C) and others.
GOST 19177-81 — rubber porous sealing gaskets for joints of prefabricated elements of building enclosing structures.
GOST 17133-83 — rubber plates for products in contact with food products.
GOST 7338-90 — rubber and rubber-fabric plates, including oil-and-gasoline-resistant (MBS) and heat-frost-acid-alkali-resistant (TMKShch) grades.
ASTM D1330 — international standard for sheet rubber gaskets for water, air and low-pressure steam.
ISO 3934-2021 — classification of materials for preformed gaskets for buildings.

Global Market

The global seals and gaskets market demonstrates steady growth. In 2025, the gaskets and seals market was valued at USD 70–77 billion. It is projected to grow to USD 94.6–107.8 billion by 2034 at a CAGR of 3.2–4.6%.

The narrower rubber seals and gaskets segment was valued at USD 72.48 billion in 2025, with a projected growth to USD 110.05 billion by 2034 (CAGR 4.75%). The EPDM gaskets segment was valued at USD 327 million in 2024, with a projected growth to USD 513 million by 2031 (CAGR 6.7%).

Key market drivers are the growth of industrial production, expansion of the oil and gas sector, development of infrastructure projects, and tightening requirements for equipment tightness and environmental safety.

Main trends include the transition to environmentally friendly materials (asbestos-free, with reduced volatile organic compound content), development of seals for hydrogen energy and electric vehicles, and the introduction of intelligent seal condition monitoring systems.

Conclusion

Rubber seals and gaskets are critically important elements of modern industry and infrastructure. The variety of rubber types — EPDM, NBR, silicone, fluoroelastomer, chloroprene, natural rubber — allows the optimal material to be selected for any operating conditions, whether aggressive chemical environments, extreme temperatures or contact with food products. The development of the regulatory framework and the expansion of the range of sealing materials ensure the reliability and safety of technical systems, while the growing global market confirms the high demand for these products in the long term.