BECA 143

Dimensions

Materials

Elastomers

ACM (Polyacrylate)

A polymer of ethyl acrylate (or butyl acrylate) containing a small amount of monomer required for cross-linking. ACM is more heat-resistant than NBR and is frequently used for automatic gearboxes.

Chemical resistance	Mineral oils (engine, gearbox, ATF oils). Atmospheric agents and ozone
Compatibility issues	Glycol-based breake fluids (Dot 3&4) Aromatic and chlorinated hydrocabons Water and steam Acids, alkalis, amines
Temperature range	-25°C to + 150°C (short-term peaks at +160°C) +150°C with special ACM grades

AEM (Ethylène - Acrylate rubber)

A copolymer of ethylene and methyl acrylate, AEM is considered more heat-resistant than ACM. Its characteristics position it as an intermediate between ACM and FKM.

Chemical resistance	Coolants Aggresive mineral oils Weathering agents Water
Compatibility issues	Aromatic solvants Strong acids Brake fluids Gearbox oils ATF oils
Temperature range	- 40°C to + 150°C

CR (Polychloroprene)

This CR-based elastomer is used in the refrigeration industry and for ventilation systems. Chloroprene was the first synthetic rubber developed and commercialized.

Chemical resistance	Paraffinic mineral oils Silicone oils and greases Water and water solvents at low temperature Refrigerants Ammonia Carbon dioxide Weathering agents and ozone
Limited chemical resistance	Naphtenic mineral oils Aliphatic hydrocarbons (propane, butane, petroleum) Glycol-based brake fluids
Compatibility issues	Aromatic hydrocarbons (benzene) Chrlotinated hydrocarbons (trichloroethylene) Polar solvents (ketones, acetone, acetic acid, ethylene-ester)
Temperature range	-40°C / +100°C (short-term peaks at +120°C)

EPDM (Ethylene - Propylene - Diene - Rubber)

Commonly used for hot water valves, cooling systems, braking circuits, dishwashers, and washing machines.

Chemical resistance	Hot water and steam up to +150°C Glycol-based (Dot 3 & 4) and silicone-based (Dot 5) brake fluids Organic and inorganic acids Cleaning agents, sodium and potassium alkalis Hydraulic fluids (HFD-R) Silicone oils and greases Polar solvents (alcohols, ketones, esters) Weathering agents and ozone
Compatibility issues	Mineral oils and greases Hydrocarbons Low gas impermeability
Temperature range	-45°C / +150°C (short-term peaks at +175°C)

FFKM (Perfluorinated Rubber)

Offers the best characteristics in terms of high-temperature resistance and excellent chemical inertness. Often used for high-temperature hydraulics and pneumatics, industrial valves, injection/carburetion, engine seals, and high vacuum.

Chemical resistance	Aliphatic and aromatic hydrocarbons Polar solvents (ketones, esters, ethers) Organic and inorganic acids Water and steam High vacuum
Compatibility issues	Refrigerants (R11, R12, R13, R113, R114, etc.), PFPE.
Temperature range	-15°C / +320°C

FKM (Fluorinated Rubber)

Chemical and cold resistance vary depending on the structure and fluorine content. Widely used for high-temperature hydraulics and pneumatics, industrial valves, injection/carburetion, engine seals, and high vacuum.

Chemical resistance	Mineral oils and greases (ASTM n°1, IRM 902, IRM 903) Flame-retardant fluids (HFD) Silicone oils and greases Vegetable oils Aliphatic and aromatic hydrocarbons Chlorinated hydrocarbons Gasoline (including high alcohol content) Weathering and ozone
Compatibility issues	Glycol-based brake fluids Ammonia gas Low molecular weight organic acids (formic and acetic acids
Temperatuer range	-20°C / +200°C (short-term peaks at +230°C) -40°C / +200°C with special FKM grades

FVMQ (Fluorosilicone Rubber)

Physical and mechanical properties are very similar to VMQ, but FVMQ offers better resistance to fuel and mineral oils. However, hot air resistance is lower than VMQ.

Chemical resistance	Aromatic mineral oils (IRM 903 oil) Fuels Low molecular weight aromatic hydrocarbons (benzene, toluene)
Temperature range	-70°C / +175°C

HNBR (Hydrogenated Nitrile Butadiene Rubber)

Obtained by selective hydrogenation of NBR butadiene groups. Commonly used for power steering and air conditioning.

Chemical resistance	Aliphatic hydrocarbons Mineral/vegetable oils and greases Flame-retardant fluids (HFA, HFB, HFC) Diluted acids/bases and salt solutions at moderate temperatures Water and steam up to +150°C Weathering and ozone
Compatibility issues	Chlorinated hydrocarbons Polar solvents (ketones, esters, ethers) Strong acids
Temperature range	-30°C / +150°C (short-term peaks at +160°C) -40°C / +150°C with special HNBR grades

NBR (Nitrile Butadiene Rubber)

The ACN content can vary from 18% to 50%. Higher ACN content improves oil and fuel resistance but reduces elasticity and compression set. NBR has good mechanical properties but low resistance to weathering and ozone.

Chemical resistance	Aliphatic hydrocarbons (propane, butane, petroleum, diesel) Mineral oils and greases Flame-retardant fluids (HFA, HFB, HFC) Diluted acids, alkaline and salt solutions at low temperatures Water (up to +100°C max)
Compatibility issues	High aromatic fuels Aromatic/chlorinated hydrocarbons Polar solvents Strong acids Glycol-based brake fluids Weathering and ozone
Temperature range	-30°C / +100°C (short-term peaks at +120°C) -40°C / +100°C with special NBR grades

VMQ (Silicone Rubber)

Often used for carburetion applications.

Chemical resistance	Animal and vegetable oils and greases Water at moderate temperature Diluted salt solutions Weathering agents and ozone
Compatibiliy issues	Superheated steam up to +120°C Low molecular weight chlorinated hydrocarbons Aromatic hydrocarbons
Temperature range	-60°C / +200°C  (short-term peaks at +230°C)

The table below provides an overview of the physical, chemical, and mechanical characteristics for each of the materials.

Characteristics	ACM	AEM	CR	EPDM	FFKM	FKM	FVMQ	HNBR	NBR	VMQ
Abrasion resistance	2	3	2	2	4	2	4	2	2	4
Acid resistance	4	3	2	2	1	1	3	1	3	3
Chemical resistance	4	2	2	1	1	1	1	2	2	2
Cold resistance	4	2	2	2	3	4	2	2	2	2
Dynamic properties	3	3	3	2	3	2	4	1	2	4
Electrical properties	3	3	3	2	1	4	1	3	3	1
Flame resistance	4	4	2	4	1	1	2	4	4	3
Heat resistance	1	1	2	2	1	1	1	1	2	1
Impermeability	1	1	2	2	2	2	4	2	2	4
Oil resistance	1	3	2	4	1	1	2	1	1	2
Ozone resistance	1	1	2	1	1	1	1	2	4	1
Tear resistance	2	3	3	1	4	3	4	2	2	4
Tensile strength	3	2	2	1	2	1	3	1	2	4
Water / Steam resistance	4	4	3	1	2	3	3	1	2	3
Weathering resistance	1	1	1	1	1	1	1	2	3	1

1. Excellent properties    2. Good properties    3. Average properties    4. Poor properties

Chemical compatibility

A "Chemical Compatibility Guide" catalog is available for download in the Documentation section. You can also use our free online "Chemical Compatibility" tool.

Both resources allow you to evaluate material behavior in contact with most existing fluids. The data displayed results from meticulous testing at room temperature and reflects the latest publications. Test results should not be considered 100% representative of reality due to the specificities of your application (additives, impurities, or high temperatures). We recommend performing your own tests to confirm compatibility for your specific application. Our technical team is at your disposal for any further information.

Technical data

Housing/shaft tolerance

The following mechanical tolerances are recommended for optimized performance:

• Housing/shaft diameter: h11

Due to the seal’s design and the nature of the sealing material, axial play is acceptable (please consult our experts).

Surface finish

Roughness	Ra µm	Rz µm	Rmax µm
Static radial	≤1.6 µm	≤ 6,3 µm	≤ 10.0 µm
Static axial	≤ 1.6 µm	≤ 6.3 µm	≤ 10.0 µm

 

The surface finish must not have a Ra < 0.05 µm.