Sizing and using rubber sheets correctly

Rubber sheets fulfil central functions in industrial applications: sealing, protection, damping and load distribution. At the same time, they often work in the background – until problems arise. A wrongly selected material thickness, an unsuitable compound or insufficient dimensioning quickly lead in practice to increased wear, loss of function or unnecessary downtime.

Particularly in an industrial environment, details decide service life and reliability. Localised overloads, unsuitable materials or a failure to allow for tolerances often only show their effects during operation. That is when costs arise that could have been avoided by clean planning in advance.

This guide shows how to dimension and use rubber sheets on a sound technical basis. The focus is on practical criteria such as load, material selection and operating conditions. The aim is a robust basis for decision-making with which you can find the right solution for your application.

Even at the planning stage, a close look at the application, load and ambient conditions is worthwhile. Anyone who works carefully here saves effort later and avoids failures.

Basics: areas of application for rubber sheets

Rubber sheets are used in virtually all industrial sectors. Typical applications are:

• Machine mounts for vibration damping
• Sealing surfaces in plant and housings
• Protective layers against abrasion and damage
• Anti-slip coverings

Depending on the application, the requirements differ considerably. While damping is the priority for a machine mount, adaptability and media resistance are what matter most for a seal.

Further information and available variants can be found under Rubber sheets.

Important material properties

Selecting the right material forms the basis of every dimensioning exercise. The following properties are particularly decisive:

The hardness (Shore A) significantly influences the deformation behaviour of the rubber sheet. Soft materials in the range of about 30 to 50 Shore adapt very well and are suitable for sealing applications. Medium hardnesses between 60 and 70 Shore offer a balanced compromise between flexibility and stability and are often used universally. Hard qualities from about 70 Shore are particularly load-bearing, but show less deformation and therefore less adaptability.

Elasticity and resilience determine how well the material returns to its original shape after a load. Especially in dynamic applications such as vibration damping or recurring loads, this factor is decisive for function and service life.

Temperature resistance also plays a central role. Depending on the area of application, rubber sheets must be able to withstand both low temperatures outdoors and elevated temperatures in machines or plant on a permanent basis. Typical service ranges extend from about –30 °C to over +100 °C, depending on the material.

Media resistance significantly influences durability. Oils, greases, chemicals or UV radiation attack many rubber compounds. The material selection must therefore always be made in the context of the actual ambient conditions.

Dimensioning rubber sheets

Dimensioning is always carried out in the context of the actual load. A clear distinction between static load (e.g. support) and dynamic load (e.g. vibrations) increases the safety of the design.

• Static: higher surface load possible, focus on pressure distribution
• Dynamic: lower permissible load, focus on damping and resilience

Decision logic (practical)

• High load + dynamic → medium hardness, greater thickness
• High load + static → higher hardness, medium thickness
• Outdoor area → choose EPDM
• Oil/fuel contact → choose NBR

For specific applications, you will find suitable solutions under Rubber sheets and via Rubber cut to size.

The right dimensioning is based on three factors: thickness, area and load.

Determining thickness

The thickness of the rubber sheet depends directly on the load and the desired function.

Application	Typical thickness
Seal	1–5 mm
Protective layer	3–10 mm
Vibration damping	10–30 mm

Too low a thickness leads to rapid wear. Too great a thickness can impair stability.

Decision aid

Application	Load	Environment	Material	Thickness
Machine mount	high, dynamic	indoors	SBR/NBR	10–30 mm
Seal	low	variable	EPDM/NBR	1–5 mm
Protective layer	medium	mechanical	SBR	3–10 mm
Outdoor area	medium	UV/weathering	EPDM	5–15 mm

Allowing for surface load

The load per area determines the necessary material thickness.

Rule of thumb:

• High load + small area = greater thickness required
• Low load + large area = lower thickness sufficient

With machine mounts, the compressive stress should be distributed evenly in order to avoid localised overloads.

Calculating surface load

Formula: force (N) / area (mm²) = surface load (N/mm²)

Practical example

A machine weighing 500 kg stands on four feet. Each foot carries about 125 kg. Converted, this corresponds to about 1,225 N per foot. If the contact area per foot is 50 × 50 mm (2,500 mm²), the result is a surface load of around 0.49 N/mm².

Result: at this load, a medium hardness (e.g. 60–70 Shore) with sufficient thickness is suitable for damping and load distribution.

For your specific application, you will receive dimensionally accurate solutions via our Rubber cut to size.

Planning in tolerances

Rubber sheets are subject to manufacturing tolerances. These must be taken into account in precision applications.

Particularly relevant are:

• Thickness tolerances
• Dimensional deviations in cutting

A suitable Rubber cut to size ensures accurate results and reduces assembly problems.

Selecting the right material

The choice of material depends heavily on the specific area of application. SBR is suitable as an economical solution for many standard indoor applications and offers solid mechanical properties. For outdoor applications or high weathering exposure, EPDM plays to its strengths, in particular through its resistance to UV radiation, ozone and moisture. As soon as oils or fuels come into play, NBR becomes the preferred choice, as this material is specifically designed for such media.

Typical application limits (guide values)

• SBR: –20 to +70 °C, limited weather resistance
• EPDM: –30 to +100 °C, very good UV and ozone resistance
• NBR: –20 to +90 °C, very good oil resistance

In practice, the suitable solution results from the interplay of load, environmental influences and desired service life. A clean coordination of these factors increases operational safety and reduces maintenance effort.

Further details can be found under SBR rubber, EPDM rubber and NBR rubber.

Common mistakes in selection and use

Many problems arise from specific misapplications in operation:

• Machine "wanders" or vibrates strongly: material too soft or thickness too low
• Cracks or embrittlement: unsuitable material for temperature or UV exposure
• Swelling of the material: wrong choice for oil or chemical contact
• Rapid abrasion: insufficient thickness or wrong hardness

These mistakes often lead to premature wear or loss of function.

Rubber compared with alternatives

Polyurethane (PU) offers higher abrasion resistance and is suitable for heavily stressed surfaces. Plastic sheets are used where requirements for elasticity are lower. Rubber remains advantageous wherever damping, adaptability and energy absorption are the priority.

For applications in mechanical engineering, you will find further solutions under Rubber sheets.

When a custom solution makes sense

Standard solutions reach their limits when special requirements apply:

• very high point loads
• strongly dynamic loads
• extreme temperatures or aggressive media

In such cases, an individual design with regard to material, hardness and geometry is recommended.

Processing and cutting

A clean cut makes assembly easier and increases service life.

Important points:

• Exact dimensions
• Allowance for tolerances
• Suitable cutting methods depending on the material

A dimensionally accurate cut ensures that the rubber sheet fulfils its function optimally.

In conclusion

A technically clean design combines load, material properties and operating conditions into a clear decision. Anyone who works with specific guide values for surface load, temperature and resilience significantly increases planning reliability.

For specific projects, an individual consultation is recommended. Via Rubber cut to size, you will receive tailor-made solutions for your application.

Frequently asked questions

How do I find the right thickness for a rubber sheet?

The right thickness depends on the load, contact area and function. For seals, 1 to 5 mm is often enough, for protective layers 3 to 10 mm and for vibration damping frequently 10 to 30 mm. The higher the load and the smaller the contact area, the more generously the rubber sheet should be dimensioned.

Which material is suitable for outdoor use?

EPDM is suitable for outdoor use in many cases. The material is very resistant to UV radiation, ozone, moisture and weathering and is therefore often chosen for outdoor applications.

When is NBR the better choice?

NBR is recommended wherever rubber sheets come into contact with oils, greases or fuels. In technical and industrial applications, NBR is therefore often the suitable solution for oil-exposed areas.

How do I calculate the surface load of a rubber sheet?

You calculate the surface load using the formula force in newtons divided by area in square millimetres. The result shows how heavily the rubber sheet is loaded per area and helps in selecting thickness and hardness.

Why does Shore hardness play an important role?

Shore hardness determines how soft or hard a rubber sheet is. Softer qualities adapt better and are suitable for sealing tasks. Harder qualities carry higher loads and deform less. The right hardness therefore directly influences function, service life and operational safety.

What happens with incorrect dimensioning?

A rubber sheet that is too thin or unsuitable can lead to premature wear, insufficient damping, material damage or loss of function. Typical consequences are cracks, swelling, instability or uneven load distribution.

When is an individual cut worthwhile?

An individual cut is worthwhile whenever precise dimensions, defined cut-outs or a clean fit are required. This improves assembly, reduces sources of error and ensures reliable function in use.

When is a custom solution worthwhile?

A custom solution is advisable for very high point loads, strongly dynamic loads, extreme temperatures or special media requirements. In such cases, material, hardness and geometry should be specifically matched to the application.

Our rubber sheets

For industry and trade, we offer a wide range of rubber sheets.

SBR rubber sheet

Our high-quality SBR rubber sheet (styrene-butadiene rubber) is the solution for numerous industrial and commercial applications. This rubber sheet is manufactured from first-class styrene-butadiene rubber and is distinguished by its outstanding physical properties.

EPDM rubber sheet

Discover the versatility and reliability of our EPDM rubber sheet, which is manufactured from ethylene propylene diene monomer (EPDM). This high-quality elastomer solution has been specially developed to meet the most demanding industrial and commercial applications.

NBR rubber sheet

The NBR rubber sheet is a high-quality industrial product that has been specially developed for applications requiring excellent resistance to oils, greases and various chemicals.

Viton rubber sheet

The Viton rubber sheet is a high-quality technical product that is used for a wide range of industrial applications. Manufactured from fluoro rubber (FKM), it offers outstanding properties that make it the ideal choice for extreme conditions.

FKM rubber sheet

The FKM rubber sheet is a high-quality technical product that is ideal for use in demanding industrial applications. Made from fluoro rubber (FKM), it is distinguished by a wide range of outstanding properties that make it the optimum choice for extreme operating conditions.

Silicone rubber sheet

The silicone rubber sheet is a first-class technical product that has been specially developed for applications placing high demands on temperature resistance and flexibility.

PUR rubber sheet

The PUR rubber sheet, made from high-quality polyurethane, is a technically advanced product that has been developed for applications placing the highest demands on abrasion resistance and mechanical load capacity.

Neoprene rubber sheet

The Neoprene rubber sheet, manufactured from high-quality chloroprene rubber (CR), is a versatile technical product that is ideal for a wide range of industrial and commercial applications.