Flat gaskets

Flat gaskets belong to the static gaskets and are used to seal two smooth sealing surfaces, so they can be regarded as contact gaskets. They are also used as an auxiliary material in flange connections. They are mainly used when components are detachably connected to each other by screw connections, as is the case with flange or housing connections, for example. The aim of using flat gaskets is to prevent the medium in question from escaping from the hollow body to be sealed. Depending on the specific application, various sealing materials are available from us at Rehm Dichtungen Ehlers GmbH.

In the area of static seals, we are primarily concerned with the group of soft material seals, which consists of the segments rubber or rubber cork seals, fibre material seals, PTFE seals and graphite seals.

In addition to this type of gasket, as a sub-area of our gasket technology, flange gaskets, cut-to-size and yard goods as well as rubber sleeves from the sub-groups are still available from us.

Properties of flat gaskets

Flat gaskets are pressed along the joint purely by external forces. Their task is on the one hand to seal and on the other hand to compensate for existing unevenness. In this way, the medium to be sealed is prevented from escaping from the hollow body through which it flows. In order to avoid leakage, a uniform surface pressure must be permanently ensured around the entire circumference of the surface to be sealed.

Depending on the material, flat gaskets can be used flexibly, are low-wear and can withstand high loads.

Areas of application for flat gaskets

Flat gaskets have an enormously wide range of applications and can be used almost anywhere. The possibility of the intended use depends on the resistance and approvals of the respective material. In principle, they are used primarily in the chemical, food and pharmaceutical industries. Other major areas of application include pipeline construction and apparatus engineering. Here, the static gaskets are installed as flange gaskets between the flanges of two connected pipes. Flat gaskets are also used in fittings, pumps and valves in a wide variety of industries.
Flat gaskets made to measure

Influencing variables for flat gaskets

The connection of two pipes by flat gaskets is an elementary component of many technical systems and apparatus. Their main task is to ensure technical tightness, which can only be guaranteed through interaction in the entire system. For this reason, several influencing factors must be considered when selecting the flat gasket.

In order to be able to make a correct material selection, the first step must be to clarify the application field of the flat gasket so that the influencing variables with regard to medium, pressure and temperature are known.

Based on the medium, it is important to clarify in advance what resistance the sealing material must have. Following the medium, the temperature range should be defined. It is important to know whether the temperature acts on the gasket constantly or alternately. It is also necessary to obtain information about the pressure range and existing internal pressures.

The different materials

In accordance with the wide range of applications with regard to the media to be sealed as well as different temperature and pressure ranges, flat gaskets made of a variety of materials are manufactured individually for customers at Rehm Dichtungen Ehlers GmbH.

The choice of material depends on whether the desired seals must be particularly resistant to chemical, thermal and/or mechanical stress. If the desired seal is to be used in the area of food or pharmaceutical products, the material must be physiologically harmless.

Commonly used materials are:

• Elastomers, such as CR, EPDM, FKM, NBR and NR
• Fibers from the well-known manufacturers Frenzelit, Klingersil, Reinz and Hecker
• foamed materials, such as sponge rubber, silicone foam and cellular rubber
• Silicone in the colors red, blue and transparent
• Polyurethane
• PTFE

Many other materials are also suitable as materials for flat gaskets. At Rehm Dichtungen Ehlers you will find a wide range of different sealing materials. Find out here about the materials we can supply you with or let us advise you. Together we will find the most suitable material for your purposes.

In addition to the correct choice of material, professional installation of the flat gasket is also decisive for the functionality of the gasket, as it has a significant influence on the stability, the leakage rate and thus the service life of the gasket used.