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BECA 239

BECA 239
beca_239_3d_v1
beca_239_3d_v2

Description

The BECA 239 profile is a U-ring type single acting rod seal with asymmetrical lips composed of a profiled rubber seal and a bronze-filled PTFE back-up ring on the back.

Advantages

Optimised sealing effect at average and higher pressures
Good extrusion resistance

Technical data

Temperature

-30°C/+200°C

Pressure

25 MPa

Speed

0.5 m/s

Medias

Mineral hydraulic oils
Fire-resistant liquids
Biocompatible fluids
Water
Others (contact our experts)

Applications

Mobile machinery
Material handling - Lifting
Hydraulic cylinders

Materials

Profiled seal

NBR 85 Shore A
FKM 80 - 85 Shore A

Back-up ring

Bronze-filled PTFE

Dimensions
Materials
Technical data

Dimensions

Installation drawingLogement Gorge Joint de tige - Housing Groove Gland Rod seal BECA 239

Materials

NBR

Nitrile rubber (NBR) is the general term for acrylonitrile-butadiene copolymer. The ACN content can vary between 18% and 50%. While the acrylonitrile content is important, the resistance to oil and fuel is more so. Conversely, the elasticity and compression set are not as good. The NBR has good mechanical properties and good wear resistance. However, its resistance to atmospheric agents and the ozone is relatively low.

Chemical resistance Aliphatic hydrocarbons (propane, butane, petroleum, diesel fuel)
Mineral oils and greases
Fire-resistant fluids (HFA, HFB and HFC)
Diluted acids, low-temperature alkaline and saline solutions
Water (up to +100°C max)
Compatibility issue Fuels with high aromatic content
Aromatic hydrocarbons (benzene)
Chlorinated hydrocarbons (trichlorethylene)
Polar solvents (ketone, acetone, acetic acid, ethylene-ester)
Strong acids
Glycol-based brake fluids
Atmospheric and ozone agents
Temperature range -30°C/+100°C
-40°C / +100°C with our low-temperature NBR

FKM

Depending on their structure and fluorine content, the chemical resistance and resistance to the cold in fluororubbers can vary. This FKM-based rubber is very often used for high-temperature hydraulics and pneumatics, for industrial valves, injection/fuel systems, motor seals and high-vacuum systems.

Chemical resistance Mineral oils and greases, ASTM n°1, IRM 902 and IRM 903 oils.
Fire-resistant liquids (HFD)
Silicone oils and greases
Mineral and vegetable oils and greases
Aliphatic hydrocarbons (propane, butane, petroleum)
Aromatic hydrocarbons (benzene, toluene)
Chlorinated hydrocarbons (trichlorethylene)
Fuel (including high alcohol content)
Atmospheric and ozone agents
Compatibility issue Glycol-based brake fluids
Ammonia gas
Organic acids with a low molecular weight (formic and acetic acids)
Temperature range -20°C/+200°C

Bronze-filled PTFE

 

PTFE is a thermoplastic polymer made of tetrafluoroethylene with exceptional properties - very low friction coefficient (adhesive friction and sliding friction are almost equal), physiologically safe for temperatures up to +200°C, excellent electrical insulation properties, and excellent chemical compatibility with the majority of fluids. On the other hand, as this material is plastic and not elastic, so it cannot easily replace rubber bases.

Between 40% and 60% of bronze is added to the PTFE as a filler. This machined material has excellent wear resistance, low creep deformation and good thermal conductivity.

Technical data

Housing Groove Gland Rod Seal - BECA 239

Extrusion gaps

Pressure
MPa
Radial extrusion gap
F/2
10 MPa 0.25
15 MPa 0.20
20 MPa 0.15
25 MPa 0.10

Surface roughness

Roughness Dynamic surface area Static surface area Groove flanks
Ra 0.1 - 0.4 µm ≤ 1.6 µm ≤ 3.2 µm
Rz 0.63 - 2.5 µm ≤ 6.3 µm ≤ 10.0 µm
Rmax 1.0 - 4.0 µm ≤ 10.0 µm ≤ 16.0 µm

Chamfers and radius

Radial section
S
Radius
R1
Radius
R2
Chamfer
C
4.00 0.20 0.40 2.00
5.00 0.40 0.70 2.50
6.00 0.70 1.10 3.00
7.50 0.80 1.10 4.00
10.00 1.00 1.10 5.00
22 dimensions found
239.0300401
Standard request
30,00 40,00 10,00 11,00
239.0350605
Standard request
35,00 60,00 15,50 17,00
239.0400501
Standard request
40,00 50,00 10,00 11,00
239.0450551
Standard request
45,00 55,00 10,00 11,00
239.0450705
Standard request
45,00 70,00 15,50 17,00
239.0500634
Standard request
50,00 63,00 13,00 14,00
239.0550684
Standard request
55,00 68,00 13,00 14,00
239.0600734
Standard request
60,00 73,00 13,00 14,00
239.0650784
Standard request
65,00 78,00 13,00 14,00
239.0650902
Standard request
65,00 90,00 18,00 20,00
239.070083I
Standard request
70,00 83,00 13,00 14,00
239.0750883
Standard request
75,00 88,00 13,00 14,00
239.0800933
Standard request
80,00 93,00 13,00 14,00
239.0851004
Standard request
85,00 100,00 13,00 14,00
239.0901054
Standard request
90,00 105,00 13,00 14,00
239.0951103
Standard request
95,00 110,00 13,50 14,50
239.1001153
Standard request
100,00 115,00 13,00 14,00
239.1101303
Standard request
110,00 130,00 13,00 14,00
239.1201403
Standard request
120,00 140,00 13,00 14,00
239.1301506
Standard request
130,00 150,00 16,00 17,00
239.1401607
Standard request
140,00 160,00 16,00 17,00
239.1601806
Standard request
160,00 180,00 16,00 17,00