NBR

Color – black

NBR is an acrylonitrile-butadiene rubber commonly known as Nitrile or BUNA. It has good mechanical properties and chemical resistance to mineral oils and greases, HFA, HFB and HFC fire retardant pressure fluids.

NBR is one of the most used elastomers in the sealing industry

NBR filled with soot and is not suitable for electrical insulation

NBR possess high hardness and for rubber elastomer has a very high resistance to abrasion (90mm³). Temperature limit: from -30°C up to +100°C (short time up to +120°C). At high temperatures the process of ageing speeds up, therefore the material becomes hard and fragile. The process of ageing starts in the atmosphere at 80°C, the ageing considerably slows down when reducing the inflow of hot air (for example, in hot oil).

Resistance

Good resistance
Average resistance
Low resistance
Mineral oils
40% aromat. fuils (leaded fuils)
Aromatic hydrocarbon (toulene, benzol)
Aliphatic hydrocarbons (propane, butane)
Biodegradable hydraulic fluid
Chlorinated hydrocarbones (trichloroethylene)
Water
Brake fluids based on glycol
Fire-resistant pneumatic fluids HFA, HFB, HFC
Silicone oil and grease (oils can cause the decrease)
Fire-resistant pneumatic fluids HFD
Adipose and vegetable oils
Acetone, acetic acid ethyl esters
Diesel petrol
Big amount of dilute acids and bases, salines at room temperature.

Application

NBR can be used for production of rod seals, piston seals, non-standard seals (special seals) and other components. NBR is mainly used in cases, where high fuel and mineral oil resistance, high elasticity and low residual strain are required, i.e. in sealing technologies, where «soft seal» is required, but NBR has a lower hardness than TPU, thus sealing out of this material have a lower resistance to extrusion with the same design. To operate at high pressures, seals NBR should be complemented by protection (supporting) elements, named “Back-up Rings”. Seals out of NBR, compared with seals of the TPU, allow a short “run dry” and can work in a more abrasive work environments, such as in high dust content in cement production. Rotary seals out of NBR may be used at higher shaft speeds than seals out of TPU, approximately doubled.

Main use

  • Wipers for special instance
  • Piston and road seals
  • Rotary seals
  • O-Rings

NBR Material Data Sheet

Properties
Value
Unit
Standard
Hardness at 20°:
85 +/-2
Shore A
DIN 53505
Density:
1,32
g/cm³
DIN ISO 1183-1
100% Modulus:
>10
N/mm²
DIN 53504
300% Modulus:
/
N/mm²
DIN 53504
Tensile strength:
>16
N/mm²
DIN 53504
Elongation at break:
>200
%
DIN 53504
Rebound resilience:
>25
%
DIN 53512
Tear strength:
>6
N/mm²
DIN ISO 34-1
Abrasion:
<90
mm³
DIN 53516
Compression set:*
<10
%
DIN ISO 815-1
Compression set:**
<10
%
DIN ISO 815-1
Compression set:***
<15
%
DIN ISO 815-1
Min. service temperature:
-30
°C
Max. service temperature (short term):
+100 (+120)
°C

*Compression set @ 23°C, 72 hours, 10% deflexion
**Compression set @ 70°C, 24 hours, 20% deflexion
***Compression set @ 100°C, 24 hours, 20% deflexio

All above established data results from random tests which were taken from the functioning production. All data was stated based on standard test-products in accordance with ISO, DIN and ASTM standards and can substantially not be extended to the completed seal. Our practical technical recommendation, either oral, written or through tests is given in conformity with our best knowledge. However, this data is to be regarded as non-obligatory advice, also taking into consideration any protective rights of a third party, and does not acquit you from making tests with our product in relation to its adaptability for the assigned process and intendment. Utilization, application and processing of the products befall completely outside of our control and are therefore solely your liability. As regards the responsibility, it will be limited to all damages in the value of the product which we delivered and you applied. Certainly, we do assure the immaculate quality of our products in concordance with our general sales and delivery conditions.