EN
Search

BECA 021

BECA 021
beca_021_3d_v1
beca_021_3d_v2

Description

The BECA 021 profile is a single acting composite rod seal composed of a profiled rubber seal and a filled PTFE or POM back-up ring. It meets the standards MIL-G-5514F and AS4716.

Advantages

Excellent extrusion resistance
Good sealing effect in static applications
Wide temperature range and excellent chemical resistance, depending on the materials selected
Housing in line with MIL-G-5514F and AS4716

Technical data

Temperature

-40°C/+200°C

Pressure

35 MPa in static applications
21 MPa in dynamic applications

Speed

1 m/s

Medias

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

Applications

Actuators
Brakes systems
Flight controls
Motors
Landing gear

Materials

Profiled seal

NBR 70 Shore A
FKM 70 Shore A
EPDM 70 Shore A
VMQ 70 Shore A

Back-up ring

Polyoxymethylene - POM
Filled PTFE

Dimensions
Materials
Technical data

Dimensions

021.010, 021.011, 021.012, 021.013, 021.014, 021.015, 021.016, 021.017, 021.018, 021.019, 021.020, 021.021, 021.022, 021.023, 021.024, 021.025, 021.026, 021.027, 021.028, 021.110, 021.111, 021.112, 021.113, 021.114, 021.115, 021.116, 021.117, 021.118, 021.119, 021.120, 021.121, 021.122, 021.123, 021.124, 021.125, 021.126, 021.127, 021.128, 021.129, 021.130, 021.131, 021.132, 021.133, 021.134, 021.135, 021.136, 021.137, 021.138, 021.139, 021.140, 021.141, 021.142, 021.143, 021.144, 021.145, 021.146, 021.147, 021.148, 021.149, 021.210, 021.211, 021.212, 021.213, 021.214, 021.215, 021.216, 021.217, 021.218, 021.219, 021.220, 021.221, 021.222, 021.223, 021.224, 021.225, 021.226, 021.227, 021.228, 021.229, 021.230, 021.231, 021.232, 021.233, 021.234, 021.235, 021.236, 021.237, 021.238, 021.239, 021.240, 021.241, 021.242, 021.243, 021.244, 021.245, 021.246, 021.247, 021.325, 021.326, 021.327, 021.328, 021.329, 021.330, 021.331, 021.332, 021.333, 021.334, 021.335, 021.336, 021.337, 021.338, 021.339, 021.340, 021.341, 021.342, 021.343, 021.344, 021.345, 021.346, 021.347, 021.348, 021.349, 021.425, 021.426, 021.427, 021.428, 021.429, 021.430, 021.431, 021.432, 021.433, 021.434, 021.435, 021.436, 021.437, 021.438, 021.439, 021.440, 021.441, 021.442, 021.443, 021.444, 021.445, 021.446, 021.447, 021.448, 021.449, 021.450, 021.451, 021.452, 021.453, 021.454, 021.455, 021.456, 021.457, 021.458, 021.459, 021.460
Installation drawingLogement Gorge Joint de tige aéronautique - Housing Groove Gland aerospace rod seal BECA 021

Materials

Profiled seal

NBR (Nitrile Butadiene Rubber)

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 (short-term peak at +120°C)
-40°C / +100°C with particular NBRs
FKM (fluorinated rubber)

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 (short-term peak at +230°C)
-40°C / +200°C with particular FKMs
EPDM (Ethylene Propylene Diene Monomer rubber)

As an Ethylene Propylene Diene Monomer copolymer, EPDM is commonly used for hot water taps, cooling systems, brake systems, dishwashers and washing machines.

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

This HNBR-based rubber is obtained through selective hydrogenation of the NBR's butadiene groups. It is commonly used for power-assisted steering and for air conditioning.

Chemical resistance Aliphatic hydrocarbons
Mineral and vegetable oils and greases
Fire-resistant fluids (HFA, HFB and HFC)
Diluted acids, saline solutions and bases for operation at an average temperature
Water and steam up to +150°C
Atmospheric and ozone agents
Compatibility issue Chlorinated hydrocarbons
Polar solvents (ketones, esters and ethers)
Strong acids
Temperature range -30°C / +150°C (short-term peak at +160°C)
-40°C / +150°C with particular HNBRs
VMQ (silicone rubber: methyl vinyl polysiloxane)

This FVMQ-based rubber is very often used in fuel systems.

Chemical resistance Animal and vegetable oils and greases
Water for operation at an average temperature
Diluted saline solutions
Atmospheric and ozone agents
Compatibility issue Superheated steam up to +120°C
Chlorinated hydrocarbons with a low molecular weight (trichlorethylene)
Aromatic hydrocarbons (benzene, toluene)
Temperature range -60°C / +200°C (short-term peak at +230°C)
FVMQ (fluorosilicone rubber)

The FVMQ has mechanical and physical properties that are very similar to those of the VMQ. However, the FVMQ offers better resistance to fuels and mineral oils. However, resistance to hot air is not as good as that of the VMQ.

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

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

Characteristics/Materials EPDM FKM FVMQ HNBR NBR VMQ
Abrasion resistant 2 2 4 2 2 4
Resistance to acids 2 1 3 1 3 3
Chemical resistance 1 1 1 2 2 2
Resistance to cold 2 4 2 2 2 2
Dynamic properties 2 2 4 1 2 4
Electrical properties 2 4 1 3 3 1
Flame resistant 4 1 2 4 4 3
Heat resistant 2 1 1 1 2 1
Sealing water 2 2 4 2 2 4
Oil resistant 4 1 2 1 1 2
Ozone resistant 1 1 1 2 4 1
Tearing resistant 1 3 4 2 2 4
Traction resistant 1 1 3 1 2 4
Water/vapour resistant 1 3 3 1 2 3
Resistance to atmospheric agents 1 1 1 2 3 1

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

Back-up ring

Polyoxymethylene - POM

Polyoxymethylene (POM or polyacetal) belongs to the thermoplastics, which have a number of advantages - strong mechanical resistance, good creep strength, high resistance to shocks, particularly at low temperatures, good wear resistance, good sliding coefficient, excellent machinability and good dielectric properties. The low water absorption coefficient, unlike polyamide (PA), also gives this material an excellent dimensional stability.

Chemical resistance

Aliphatic hydrocarbons (propane, butane, petroleum, diesel fuel)
Mineral oils and greases
Fire-resistant fluids (HFA, HFB and HFC)
Water

Compatibility issue Acids
Temperature range -50°C/+115°C
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 +260°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.

Chemical compatibility

A "Chemical compatibility guide" catalogue can be downloaded from the Documentation section. You can also use our online "Chemical compatibility" tool free of charge.

These two tools give you the option of measuring the behaviour of our materials that come into contact with the majority of existing fluids. The data displayed is the result of rigorous testing of the ambient temperature and in consultation with previous publications. Test results are not fully representative due to the specific features of your application. The tests performed actually do not consider additives and impurities that may exist under the actual conditions of use, nor the potential elevation of temperatures. Other parameters can also alter the behaviour of our materials, such as the hardness, persistence, abrasion, etc. We therefore recommend performing your own tests to verify the compatibility of our materials according to your specific application. Our technical team can provide you with any additional information.

Technical data

Housing Groove Aerospace Rod Seal - BECA 021

Groove widths and extrusion gaps

Series Groove width Extrusion gaps
F
L1
min - max
L2
min - max
010 - 012 2.39 - 2.52 3.81 - 4.06 0.10
013 - 028 0.13
110 - 125 3.58 - 3.83 4.65 - 4.90 0.13
126 - 131 0.15
132 - 149 0.18
210 - 222 4.78 - 5.03 5.97 - 6.22 0.13
223 - 225 0.15
226 - 245 0.18
246 - 247 0.20
325 - 327 7.14 - 7.39 8.48 - 8.73 0.15
328 - 349 0.18
425 - 449 9.53 - 9.78 12.07 - 12.32 0.23
450 - 460 0.25

Tolerances on the rod diameters and groove diameters

Series Tolerance on
rod diameter
Ød1
Tolerance on
groove diameter
ØD1
010 - 012 -0.025/0 0/+0.025
013 - 349 -0.050/0 0/+0.050
425 - 446 -0.078/0 0/+0.076
447 - 460 -0.076/0 0/+0.100

Surface roughness

Roughness Dynamic surface area Static surface area Groove flanks
Ra 0.05 - 0.2 µm ≤ 1.6 µm ≤ 3.2 µm
Rz 0.4 - 1.6 µm ≤ 6.3 µm ≤ 10.0 µm
Rmax 0.63 - 2.5 µm ≤ 10.0 µm ≤ 16.0 µm

Chamfers and radius

Series Radius Chamfer
R1
min - max
R2
min - max
C
010 - 028 0.13 - 0.26 0.13 - 0.38 2.00
110 - 149 0.13 - 0.26 0.13 - 0.38 2.50
210 - 222 0.13 - 0.26 0.13 - 0.38 3.00
223 - 247 0.13 - 0.26 0.25 - 0.64 3.50
325 - 349 0.13 - 0.26 0.51 - 0.89 4.00
425 - 460 0.13 - 0.26 0.51 - 0.89 4.50
158 dimensions found
021.328
Standard request
328 47,57 57,02 57,02 7,14 8,48
021.329
Standard request
329 50,75 60,2 60,20 7,14 8,48
021.330
Standard request
330 53,92 63,37 63,37 7,14 8,48
021.331
Standard request
331 57,10 66,55 66,55 7,14 8,48
021.332
Standard request
332 60,27 69,72 69,72 7,14 8,48
021.333
Standard request
333 63,45 72,9 72,90 7,14 8,48
021.334
Standard request
334 66,62 76,07 76,07 7,14 8,48
021.335
Standard request
335 69,80 79,25 79,25 7,14 8,48
021.336
Standard request
336 72,97 82,42 82,42 7,14 8,48
021.337
Standard request
337 76,12 85,57 85,57 7,14 8,48
021.338
Standard request
338 79,30 88,75 88,75 7,14 8,48
021.339
Standard request
339 82,47 91,92 91,92 7,14 8,48
021.340
Standard request
340 85,65 95,1 95,10 7,14 8,48
021.341
Standard request
341 88,82 98,27 98,27 7,14 8,48
021.342
Standard request
342 92,00 101,45 101,45 7,14 8,48
021.343
Standard request
343 95,17 104,62 104,62 7,14 8,48
021.344
Standard request
344 98,35 107,8 107,80 7,14 8,48
021.345
Standard request
345 101,52 110,97 110,97 7,14 8,48
021.346
Standard request
346 104,70 114,15 114,15 7,14 8,48
021.347
Standard request
347 107,87 117,32 117,32 7,14 8,48
021.348
Standard request
348 111,05 120,5 120,50 7,14 8,48
021.349
Standard request
349 114,22 123,67 123,67 7,14 8,48
021.425
Standard request
425 114,22 126,34 126,34 9,53 12,07
021.426
Standard request
426 117,40 129,51 129,51 9,53 12,07
021.427
Standard request
427 120,57 132,69 132,69 9,53 12,07
021.428
Standard request
428 123,75 135,86 135,86 9,53 12,07
021.429
Standard request
429 126,92 139,04 139,04 9,53 12,07
021.430
Standard request
430 130,10 142,21 142,21 9,53 12,07
021.431
Standard request
431 133,27 145,39 145,39 9,53 12,07
021.432
Standard request
432 135,45 148,56 148,56 9,53 12,07
021.433
Standard request
433 139,62 151,74 151,74 9,53 12,07
021.434
Standard request
434 142,80 154,91 154,91 9,53 12,07
021.435
Standard request
435 145,97 158,09 158,09 9,53 12,07
021.436
Standard request
436 149,15 161,26 161,26 9,53 12,07
021.437
Standard request
437 152,32 164,44 164,44 9,53 12,07
021.438
Standard request
438 158,67 170,79 170,79 9,53 12,07
021.439
Standard request
439 165,02 177,14 177,14 9,53 12,07
021.440
Standard request
440 171,37 183,49 183,49 9,53 12,07
021.441
Standard request
441 177,72 189,84 189,84 9,53 12,07
021.442
Standard request
442 184,07 196,19 196,19 9,53 12,07
021.443
Standard request
443 190,42 202,54 202,54 9,53 12,07
021.444
Standard request
444 196,77 208,89 208,89 9,53 12,07
021.445
Standard request
445 203,12 215,24 215,24 9,53 12,07
021.446
Standard request
446 215,82 227,94 227,94 9,53 12,07
021.447
Standard request
447 228,52 240,64 240,64 9,53 12,07
021.448
Standard request
448 241,22 253,34 253,34 9,53 12,07
021.449
Standard request
449 253,92 266,04 266,04 9,53 12,07
021.450
Standard request
450 266,62 278,74 278,74 9,53 12,07
021.451
Standard request
451 279,32 291,44 291,44 9,53 12,07
021.452
Standard request
452 292,02 304,14 304,14 9,53 12,07
021.453
Standard request
453 304,72 316,84 316,84 9,53 12,07
021.454
Standard request
454 317,42 329,54 329,54 9,53 12,07
021.455
Standard request
455 330,12 342,24 342,24 9,53 12,07
021.456
Standard request
456 342,82 354,94 354,94 9,53 12,07
021.457
Standard request
457 355,52 367,64 367,64 9,53 12,07
021.458
Standard request
458 368,22 380,34 380,34 9,53 12,07
021.459
Standard request
459 380,92 393,04 393,04 9,53 12,07
021.460
Standard request
460 393,62 405,74 405,74 9,53 12,07
   1 2