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<< "Technical Infos"


Our seals are  -depending on the DIN-specifications - produced with elastomeres according to DIN 681-1 and DIN 681-2.

ElastomereMainly the following elastomer-types are used :

EPDM Rubber (Ethylene Propylene Diene Monomer)

EPDM is a terpolymer elastomere and belongs to the copolymeres with sated polymerframe. Because of its excellent resistance to ozone, sunlight and severe weather conditions, EPDM is ideal for outdoor service. It has good resistance to alkalis, acids and oxygenated solvents and therefore it is an ideal sealing material.

NBR Rubber (Nitrile or Acrylonitrile Butadiene)

NBR Rubber can be offered as an alternative material for instances when the drainage effluent is contaminated by hydrocarbons, oils, fats and greases. It should be noted that the nitrile compound is classed as medium grade and is therefore only suitable for drainage applications.

ATTENTION: If you want to use our NBR-sealing for sewage foreign purposes, please contact our sales office. There you will be informed if the seal is suitable for your purpose.

SBR Rubber (Styrene Butadiene)

SBR Rubber as one of the most common synthetic caoutchouc comes with similar properties like NR (Natural Rubber), but loses its elastic requirement in evidence.

NR (Natural Rubber)

NR is mainly made out of polyisopren and gets extracted  from plants that grow in tropical areas, especially euphorb family.It has good elastic properties but ages quite fast.

Characteristics EPDM NBR SBR NR
Ozone Resistance excellent adequate adequate adequate
Acid Resistance excellent adequate satisfactory satisfactory
Liquor Resistance excellent adequate satisfactory satisfactory
Electric Resistance good poor good excellent
Impact Rebound satisfactory satisfactory satisfactory good
Elongation at Break satisfactory good good excellent
Permeability adequate good adequate poor
Oil Resistance adequate good poor unsatisfactory
Fuel Resistance poor good unsatisfactory unsatisfactory
Temperature Window - 50° to +150° - 30° to +100° - 40° to +80° - 40° to +80°
Short-term Peak Temperature + 160° + 130° + 130° + 130°


For most of our seals we use high-quality EPDM caoutchouc. Essentially there are used nature rubber or synthetic caouchouc. Our EPDM -mixture contains diffrent additives which ensure the permanent sealing techniqe that is desired.

By heating the EPDM rubber it gets vulcanized. After this process the rubber is extremely elastic. It is possible to form the material at will without loosing its initial shape.

EPDM is resistant to most of the acids and chemical bases that appear in waste water (detailed inventory list is available). At the same time EPDM resists temperatures up to 160°C. As constant load the temperature is 130°C.