What are seals?

Seals are mechanical elements that seal two or more components against each other to prevent the escape or entry of media such as oil, water, air, gas or chemicals. They play a central role in technical systems, as they ensure the functional reliability, service life and efficiency of systems.

The operating principle of a gasket is based on the creation of a closed system between the surfaces to be sealed. Under pressure, the elastic sealing material is deformed and adapts to the microscopic unevenness of the contact surfaces - creating a tight barrier.

Seals can be divided into different categories:

  • Static seals: stationary sealing points, e.g. flange connections or Housing cover.
  • Dynamic seals: sealing elements during relative movement, e.g. Radical shaft seals or piston seals.

 

Functions & applications of seals

The main function of a seal is to reliably separate or contain media. In addition, rubber seals are often also used for noise reduction, vibration insulation and thermal separation.

Typical areas of application are

  • Mechanical and plant engineering: Sealing of hydraulic, pneumatic and cooling systems
  • Automotive industry: engine, transmission and body seals to prevent oil or fuel leaks
  • Medical technology: sterile sealing of fluid or air ducts
  • Electrical engineering: Protecting sensitive components from moisture or dust
  • Building technology: window, door and pipework seals for energy saving and sound insulation
  • Chemical industry: Sealing reactors, pumps and fittings against aggressive media

 

Seals fulfil several technical tasks at the same time:

  • Sealing against pressure and temperature differences
  • Compensation of tolerances and component movements
  • Reduction of friction and wear on contact surfaces
  • Ensuring functionality over long operating times

 

Depending on the requirements, seals are designed as simple flat rings, complex profile shapes or customised elastomer components. The correct selection and design are crucial in order to avoid leaks, failures or consequential damage.

 

Gasket components & materials

Seals can be made from a variety of materials - depending on the medium, pressure, temperature and chemical resistance. The selection of the right material determines the performance and service life of the seal:

  • NBR (nitrile rubber): Oil and fuel resistant, widely used in hydraulics
  • EPDMWeather, ozone and vapour resistant, for applications in water and heating systems or in outdoor areas
  • FKM (Viton®): Resistant to high temperatures and aggressive media
  • Silicone (VMQ): High elasticity over a wide temperature range, frequently used in food and medical technology
  • Thermoplastics: PTFE (Teflon®), POM or PE for low-friction and chemically resistant sealing systems
  • Metallic seals: Aluminium, brass or Stainless steel for high-pressure and high-temperature applications
  • Composite materials: Combinations of metal carriers and elastomer layers for improved dimensional stability

 

Seals are typically used in the Injection Molding-, Press-, Extrusions- or stamping processes. Customised material combinations mean that seals can also be designed for extreme operating conditions such as temperatures of over 200 °C, vacuum applications and high-pressure systems.