An uncompromising commitment to quality

Safety requires outstanding quality. With a strict, certified quality management, exclusive in-house assembly and carefully chosen suppliers, Gelbau consequently focuses on uncompromising product quality “Made in Germany”.

First-class materials are the basis for the maximised functionality and long life cycles of our products. With the two rubbers NBR and EPDM, Gelbau has opted for materials that make an important contribution to the applicational safety.

Internat. abbreviation NBR EPDM
Hardness range / shore 40 to 90 35 to 90
Tear resistance N/mm²
at +20 °C
up to
approx. 20
up to
approx. 20
Tensile deformation up to
approx. 450 %
up to
approx. 450 %
Rebound resilience at +20 °C satisfactory good
Resistance to
wear and abrasion
good good
Resistance to
permanent deformation
good good
General resistance to
weather conditions
good excellent
Resistance to ozone satisfactory excellent
Resistance to oil excellent low
Resistance to fuel good low
Gas impermeability good satisfactory
Resistance to solvents partly good low to
satisfactory
General resistance to acids satisfactory good
Dielectric characteristic low very good
Thermal stability
short-term
approx.
−40 to +150 °C
approx.
−50 to +170 °C
Thermal stability
longer-term
approx.
−30 to +120 °C
approx.
−30 to +140 °C
resistance to steam good very good
(General material specification)

NBR – Nitrile butadiene rubber

Synthetic special-quality rubber with high swell-resistance to fuels, oil, grease and aliphatic solvents. Not recommended in conjunction with aromatic solvents, pure benzene, toluene, and ozone or sunlight exposure.

EPDM – Ethylene propylene
diene monomer

Synthetic all-purpose rubber with excellent resistance to aging, ozone, sunlight, weather conditions and other environmental factors as well as alkalis, corona and various dyes and chemicals. Not resistant to hydrocarbon solvents, turpentine or petrol.