Choosing the best gasket material depends on what the gasket needs to seal, the temperature and pressure it will operate at, and the environment in which it will be used.

There is no single gasket material that is best for every application. A material that performs extremely well with oil may be unsuitable for hot water or steam, while a material that is excellent at high temperatures may not provide the required chemical resistance.

Common gasket materials include Flexoid, non-asbestos gasket sheet, N8094 and similar compressed fibre materials, cork, silicone, FKM, neoprene, EPDM, nitrile, silicone sponge, neoprene/EPDM sponge and FKM sponge.

Other specialist materials, including PTFE, graphite and expanded PTFE, may also be appropriate where particularly demanding chemical, temperature or sealing requirements exist.

This guide explains the main gasket materials, their properties and the applications for which they are commonly used.

How Do You Choose the Best Gasket Material?

Before selecting a gasket material, there are several important factors to consider.

1. What are you trying to seal?

The first question is what fluid, gas or substance the gasket will come into contact with.

For example, the requirements for sealing:

- Water
- Steam
- Oil
- Fuel
- Chemicals
- Air
- Gas
- Refrigerants
- Food products

can all be very different.

2. What temperature will the gasket experience?

Temperature is one of the most important factors in gasket material selection.

A gasket operating at room temperature may have very different requirements from one exposed to 200°C or more.

It is also important to consider whether the gasket will experience continuous heat, intermittent heat or rapid temperature changes.

3. What pressure will the gasket withstand?

The gasket must be capable of maintaining a seal at the application's operating pressure.

Pressure, flange design, gasket thickness, compression and surface finish can all affect gasket performance.

4. Is the application static or dynamic?

Most traditional gaskets are used in static sealing applications, where the two surfaces do not move relative to one another.

If there is movement, vibration or repeated compression, a different sealing material or design may be required.

5. What are the flange or mating surfaces like?

The condition and design of the surfaces being sealed can influence the choice of gasket.

Factors include:

- Flange condition
- Surface finish
- Flatness
- Bolt loading
- Flange rigidity
- Available compression
- Gap between surfaces

A material that works well on one flange design may not be suitable for another.

Gasket Material Comparison

The following table provides a general overview of commonly used gasket materials and their typical applications.

The figures above are general material characteristics. The actual performance of a gasket depends on the particular grade, thickness, formulation and operating conditions.

Flexoid Gasket Material

Flexoid is a traditional gasket material used extensively in industrial sealing applications.

Flexoid materials are commonly based on cellulose or fibre construction and are designed to provide reliable sealing when compressed between mating surfaces.

They can be suitable for applications involving:

- Water
- Oils
- Fuels
- General industrial fluids
- Pipework
- Pumps
- Flanges
- Machinery

Flexoid is particularly useful where a cost-effective, compressible sheet gasket material is required.

The exact suitability depends on the specific Flexoid grade and the operating conditions.

Non-Asbestos Gasket Material

Non-asbestos gasket sheet was developed as an alternative to traditional asbestos-containing gasket materials.

Modern non-asbestos gasket materials commonly use a combination of synthetic fibres, fillers, elastomers and other reinforcing materials to provide the required sealing performance.

They are widely used for:

- Pipe flanges
- Pumps
- Valves
- Industrial machinery
- Water systems
- Oil systems
- General engineering applications

Non-asbestos materials are available in different grades, allowing the material to be matched to different temperatures, pressures and media.

N8094 and Similar Compressed Fibre Gasket Materials

N8094 and similar compressed fibre gasket materials are used where a more robust sheet gasket material is required for industrial sealing applications.

Compressed fibre gasket materials can provide a useful combination of:

- Compressibility
- Strength
- Sealing performance
- Temperature resistance
- Fluid resistance

The correct grade should always be selected according to the application.

If you are replacing an existing gasket, the original material specification, thickness and operating conditions should be considered rather than simply matching the material by appearance.

Cork Gasket Material

Cork gasket material is particularly useful where a gasket needs to be highly compressible and conform to uneven or imperfect surfaces.

Cork is commonly used in:

- Automotive applications
- Engine covers
- Oil pans
- Gearboxes
- Pumps
- Flanges
- Machinery covers

Cork and cork-rubber materials can provide good resistance to oils and fuels while remaining relatively soft and compressible.

Cork can therefore be an excellent choice for low-pressure sealing applications where high compressibility is important.

Silicone Gasket Material

Silicone rubber is one of the most versatile gasket materials available.

It is particularly well known for its excellent temperature resistance and flexibility.

Depending on the grade, silicone can provide useful resistance to:

- High and low temperatures
- Ozone
- UV exposure
- Weathering
- Ageing
- Moisture

Silicone is commonly used in:

- Food processing
- Medical equipment
- Electrical equipment
- Electronics
- Automotive applications
- Industrial machinery
- High-temperature applications

Specialist silicone grades are also available for applications requiring particular properties such as flame resistance, electrical conductivity, metal detection or food-contact compliance.

View silicone sheet from TYM Seals & Gaskets.

FKM Gasket Material

FKM, also commonly referred to as a fluoroelastomer and often associated with the trade name Viton™, is a high-performance gasket material.

FKM is particularly useful when resistance to oils, fuels, hydrocarbons, chemicals and high temperatures is required.

Common applications include:

- Automotive
- Aerospace
- Oil and gas
- Chemical processing
- Industrial machinery
- Fuel systems
- High-temperature sealing

FKM can be manufactured as sheet and converted into bespoke gaskets.

It is often chosen where standard nitrile or other general-purpose rubber materials cannot provide the required combination of temperature and chemical resistance.

View FKM rubber sheet from TYM Seals & Gaskets.

Neoprene Gasket Material

Neoprene, also known as chloroprene rubber, is a versatile synthetic rubber used for a wide range of sealing applications.

Neoprene provides a useful balance of:

- Flexibility
- Mechanical strength
- Weather resistance
- Ozone resistance
- Moderate oil resistance
- Water resistance

It is commonly used for:

- Industrial gaskets
- Outdoor equipment
- Enclosures
- Machinery
- HVAC applications
- General engineering

Neoprene can be a good choice where a gasket needs to withstand outdoor conditions while providing general-purpose sealing performance.

EPDM Gasket Material

EPDM is particularly well suited to applications involving water, steam, weathering and ozone.

EPDM provides excellent resistance to:

- Water
- Hot water
- Steam
- Ozone
- UV exposure
- Weathering Ageing

It is commonly used in:

- Plumbing
- Water systems
- HVAC
- Outdoor equipment
- Automotive cooling systems
- Industrial equipment

One of EPDM's main limitations is its poor resistance to many oils and hydrocarbons.

Therefore, EPDM would generally not be the first choice for an oil-sealing application where nitrile or FKM may be more appropriate.

Nitrile Gasket Material

Nitrile rubber (NBR) is one of the most widely used elastomers for oil-resistant sealing.

Its main strengths include good resistance to:

- Mineral oils
- Fuels
- Hydraulic fluids
- Greases
- Petroleum-based products

Nitrile is widely used in:

- Automotive equipment
- Hydraulic systems
- Industrial machinery
- Pumps
- Engines
- Oil seals
- General engineering

Nitrile is often an excellent cost-effective alternative to FKM where the temperature and chemical requirements do not justify the use of a higher-performance fluoroelastomer.

Silicone Sponge Gasket Material

Silicone sponge is different from solid silicone sheet.

The cellular structure gives silicone sponge a soft, compressible construction that makes it particularly useful where a gasket needs to accommodate:

- Uneven surfaces
- Larger gaps
- Low compression forces
- Thermal expansion
- Irregular surfaces

Silicone sponge also retains many of the useful properties associated with silicone rubber, including good temperature resistance, weather resistance and ageing resistance.

Typical applications include:

- Doors
- Enclosures
- Electrical cabinets
- Ovens
- Industrial equipment
- Medical equipment
- HVAC systems

Silicone sponge is available in different densities and grades, so the correct material should be selected according to the application.

Neoprene / EPDM Sponge Gasket Material

Neoprene/EPDM sponge is a popular choice for general-purpose compression sealing.

It provides a combination of:

- Flexibility
- Compressibility
- Weather resistance
- Ozone resistance
- Good ageing characteristics

It is commonly used for:

- Enclosure doors
- Access panels
- Cabinets
- Machinery
- HVAC equipment
- Outdoor equipment

The sponge construction allows the material to compress and conform to the mating surfaces, making it useful for applications where a solid rubber gasket would require excessive compression.

FKM Sponge Gasket Material

FKM sponge is a specialist gasket material designed for applications requiring the combination of cellular sealing with FKM's chemical and temperature resistance.

It can be particularly useful where a conventional sponge material would not provide sufficient resistance to:

- High temperatures
- Oils
- Fuels
- Hydrocarbons
- Aggressive chemicals

FKM sponge is generally a more specialist and higher-cost option, but it can provide significant advantages in demanding applications.

PTFE Gasket Material

PTFE is another important gasket material and should be considered where exceptional chemical resistance is required.

PTFE provides excellent resistance to a very wide range of chemicals and can operate across a broad temperature range.

It is commonly used in:

- Chemical processing
- Pharmaceutical equipment
- Food processing
- Aggressive chemical applications
- Pipework
- Flanges

PTFE has different mechanical characteristics from elastomeric materials, so gasket design and installation are particularly important.

Graphite Gasket Material

Graphite is commonly used where extremely high-temperature resistance is required.

Flexible graphite can provide excellent resistance to high temperatures and can be used in demanding industrial sealing applications.

Typical applications include:

- High-temperature pipework
- Steam systems
- Industrial equipment
- Exhaust systems
- Boilers
- Heat exchangers

Graphite is a specialist material and should be selected based on the exact temperature, pressure and media involved.

Which Gasket Material Is Best for Water?

For water applications, EPDM is often an excellent choice, particularly where hot water or outdoor exposure is involved.

Other materials may also be suitable depending on the application.

Which Gasket Material Is Best for Oil?

For oil applications, nitrile and FKM are two of the most common choices.

Nitrile provides excellent oil resistance and is often the economical option.

FKM is generally preferred where the application also involves higher temperatures, fuels, hydrocarbons or more aggressive chemicals.

Cork and cork-rubber materials can also be suitable for certain low-pressure oil applications.

Which Gasket Material Is Best for High Temperatures?

For high-temperature applications, the best material depends on what the gasket is sealing.

Materials that may be considered include:

- Silicone
- FKM
- Graphite
- Specialist non-asbestos gasket materials
- Specialist PTFE grades

However, simply choosing the material with the highest published temperature rating is not enough.

The material must also be compatible with the fluid, pressure and sealing conditions.

For example, FKM has excellent high-temperature performance but may not be the best material for prolonged steam exposure, where EPDM or graphite may be more appropriate depending on the application.

Which Gasket Material Is Best for Chemicals?

There is no universal chemical-resistant gasket material.

The correct material depends entirely on the chemical involved.

For example:

FKM – excellent for many oils, fuels and hydrocarbons
EPDM – excellent for water, steam and many polar chemicals
PTFE – exceptional resistance to a very wide range of chemicals
Silicone – useful for selected chemical and temperature applications
Nitrile – excellent for many oils and fuels
Neoprene – useful for selected oils, water and outdoor applications

Chemical concentration and temperature can significantly change compatibility.

For aggressive chemical applications, the specific chemical, concentration and operating temperature should always be provided when selecting a gasket.

Solid Rubber or Sponge Gasket?

Another important consideration is whether you need a solid rubber gasket or sponge gasket.

Solid rubber materials such as silicone, FKM, EPDM and nitrile are generally used where a relatively thin, robust gasket is required.

Sponge materials such as silicone sponge, neoprene/EPDM sponge and FKM sponge are useful where greater compression is required.

The correct choice depends on the joint design and available compression.

How Thick Should a Gasket Be?

There is no universal gasket thickness.

The correct thickness depends on:

- Flange design
- Surface condition
- Bolt loading
- Required compression
- Operating pressure
- Temperature
- Gasket material
- Joint design

Using a gasket that is unnecessarily thick does not automatically improve sealing performance.

In some applications, a thinner gasket can provide better sealing and stability, while other applications require a thicker or more compressible material to compensate for surface irregularities.

How Do I Know Which Gasket Material I Need?

If you are unsure which gasket material to use, the most useful information to provide is:

1. What are you sealing?

2. What fluid or chemical will contact the gasket?

3. What is the operating temperature?

4. What is the operating pressure?

5. What are the gasket dimensions?

6. Is the application static or dynamic?

7. What material is currently being used?

8. Are there any required approvals or certifications?

With this information, it is much easier to select the correct gasket material.

Gasket Materials from TYM Seals & Gaskets

TYM Seals & Gaskets supplies a comprehensive range of rubber, silicone, sponge and sheet gasket materials for industrial and specialist applications.

Our materials include:

- Flexoid
- Non-asbestos gasket sheet
- N8094 and similar compressed fibre materials
- Cork
- Silicone
- FKM
- Neoprene
- EPDM
- Nitrile
- Silicone sponge
- Neoprene/EPDM sponge
- FKM sponge
- PTFE

Other specialist materials

We can supply sheet materials or manufacture bespoke gaskets and seals to drawings, dimensions, samples or specific requirements.

With extensive experience across silicone and rubber sealing applications, TYM can help you select a suitable material based on the conditions in which the gasket will operate.

View TYM's range of gasket and sealing materials.

Frequently Asked Questions About Gasket Materials

What is the best gasket material?

There is no single best gasket material. The correct material depends on the temperature, pressure, fluid, chemical exposure and joint design. Common options include silicone, FKM, EPDM, nitrile, non-asbestos gasket sheet, cork and PTFE.

What is the best gasket material for oil?

Nitrile and FKM are commonly used for oil applications. Nitrile is often a cost-effective option, while FKM is particularly useful where higher temperatures or more demanding chemical conditions are involved.

What is the best gasket material for water?

EPDM is often an excellent choice for water, particularly hot water and outdoor applications. Silicone and certain non-asbestos materials can also be suitable depending on the application.

What is the best gasket material for steam?

EPDM, graphite and specialist gasket materials can be suitable for steam applications. The correct choice depends on the steam temperature, pressure and duration of exposure.

What is the best gasket material for high temperatures?

Silicone, FKM, graphite and specialist gasket materials can all be suitable for high-temperature applications. The correct choice depends on the temperature as well as the fluid or chemical being sealed.

Is FKM better than nitrile for gaskets?

Not necessarily. FKM generally provides superior high-temperature, fuel and chemical resistance, while nitrile offers excellent oil resistance at a lower cost. The application determines which is better.

Is EPDM good for oil?

Generally, no. EPDM has excellent resistance to water, steam, ozone and weathering but is generally unsuitable for many mineral oils and hydrocarbons.

Is silicone good for gaskets?

Yes. Silicone is an excellent gasket material for many applications, particularly where high or low temperatures, flexibility, weather resistance or specialist properties are required.

What is the difference between silicone and silicone sponge?

Solid silicone is a dense rubber material, while silicone sponge has a cellular structure that makes it much softer and more compressible. Silicone sponge is particularly useful for doors, enclosures and applications requiring greater compression.

What is the difference between FKM and FKM sponge?

FKM is a solid fluoroelastomer, while FKM sponge is a cellular version designed to provide greater compressibility. Both can offer useful temperature and chemical resistance, but they are intended for different sealing applications.

Can TYM manufacture bespoke gaskets?

Yes. TYM Seals & Gaskets can manufacture bespoke rubber and silicone gaskets from drawings, dimensions, samples and specific material requirements.

Not sure which gasket material you need? Contact TYM Seals & Gaskets with details of the temperature, pressure, fluid or chemical and gasket dimensions, and we can help you select a suitable material.