Typical gasket paper thickness ranges from 0.15mm to 3.00mm, with many manufacturers following the principle that thickness follows flange condition and pressure.
Choosing the correct gasket sheet thickness should be decided upon based on your specific project and application requirements.
Utilising the elements of the raw sheet, soft-cut gaskets are typically used within low-to-medium pressure systems, performing well under low bolt loads, preventing leaks and contamination.
SSP offers a range of gasket materials and sealing solutions, and our team is always available to answer your queries.
What is gasket paper?
Gasket paper, or gasket sheeting, consists of large sheets of raw materials that are used to manufacture gaskets.
These sheets are flexible and can be customised and cut to specific sizes and shapes, depending on requirements.
This means you have a choice of material and also sheet thickness to match your application for which the gasket is intended.
Paper gasket material can range from cork gasket paper and silicone rubber compounds, making these gaskets suitable for machinery and pipework systems due to their resistance to high pressure and temperature.
Paper gasket sheets are often purchased in large quantities, where numerous gaskets can be manufactured at once. Providing a cost-effective and fast turnaround solution.
How thick should gasket paper be?
Gasket paper thickness will depend on the application the gasket will be placed within and the requirements of the system.
Thin gasket paper offers:
- Reduction in the output emissions from the cutting process.
- Reduction in product loss.
- Better torque retention
- Increase in gasket blowout resistance.
Thicker gasket paper:
- Can fill flange irregularities.
- Offers good tolerance to flange misalignment.
- Provides a sound sealing solution between the flange surface and the gasket.
However, paper gasket thickness will depend on requirements, and thin gasket sheeting may not always provide the best sealing option, as flatter flanges may be a more critical element.
The table below provides a guide, highlighting the thickness to application:
| Thickness | Typical use | Additional Information |
| 0.15 to 0.40 mm | Suitable for light duty, flat true flanges, and low-pressure applications i.e. fuel pumps, precision applications. | Seals best on good surfaces; however, if this sheeting is too thin it can fail to seal on rough flanges. |
| 0.50 to 0.80 mm | Good for general automotive and low-pressure industrial use, i.e. small engines, gearboxes, water pumps etc. | Common all-round range, great for tight tolerances. |
| 1.00 to 1.50 mm | Suitable for rougher or slightly uneven flanges and larger joints. | More conformable in high pressure and temperature applications, however, make sure to check bolt load. |
| 2.00 to 3.00 mm+ | Ideal for warped, rough or large-diameter flanges, and applications operating low pressure. | The thicker gasket sheet conforms to imperfect faces however; it is not suitable for high pressure applications. |
| Up to 6.4 mm | Specialist sheet grades, speak with SSP to find out more. | Specify your application with SSP and see how we can help you. |
How to choose the right thickness
Choosing the right and most suitable paper gasket sheet thickness should be determined based on gasket size, flange flatness, surface finish, pressure, and bolt load.
For example, thicker gasket sheets will have a lower pressure rating compared to thinner gasket sheeting.
When we look at flange flatness, you must consider any flange irregularities, i.e., warping, any visible damage, tolerance levels, etc.
The importance of gasket thickness and paper gasket material cannot be underestimated, and choosing the right one for standard raised face flanges, flat-faced flanges, nonstandard flanges, or even large equipment flanges requires careful consideration and reference to the appropriate manufacturing data sheets.
Gasket paper materials
The most common gasket paper materials include:
Nitrile
A synthetic rubber that offers a high level of resistance to water and gases. Typically used for gaskets required in the automotive sector.
Cork
A highly flexible and compressible gasket sheeting option, cork gasket materials sit well in flange irregularities and are most suitable for applications where there is low to medium bolt pressure.
CNAF
Offering grade X to Y specifications, our compressed non-asbestos fibre (CNAF) works well in high-temperature applications and also offers a high level of chemical resistance. Suitable across multiple sectors, including harsh environments.
Graphite
Able to withstand high-pressure and temperature situations, graphite sheet gaskets are most suitable for engine and exhaust systems, as well as for pumps and piping solutions.
Note: Asbestos materials have been banned in the UK since 1999 under the Asbestos (Prohibitions) (Amendment) Regulations 1999, with CNAF as the replacement offering a safe and high-performing gasket sheeting alternative. Further information can be found on the Health and Safety Executive website.
FAQ
Question: What is the most common gasket paper thickness?
Answer: For general applications, the most common paper gasket is 1.5mm in thickness. Offering optimal performance and good levels of resistance to blowout.
Question: Can a gasket be too thick?
Answer: Yes. You should always work to the manufacturer’s specifications and guidelines, working within the specified tolerances and compressibility of the application.
Question: Is asbestos gasket paper still available in the UK?
Answer: No. This type of gasket material has been banned in the UK since 1999. CNAF is now the safer and high-performing equivalent.
Question: How do I know what thickness I need?
Answer: Your decision should be based on gasket size, flange surface, flange flatness, and the pressure and bolt load of the application.
There are a number of options and considerations when choosing the right gasket thickness and material, and you need to find the most appropriate solution for your application.
Contact us today for more information about gasket paper and high-performing sealing solutions.
