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BECA 508S

BECA 508S

Description

The BECA 508S profile is a double acting composite piston seal composed of a filled PTFE friction ring, two static O'Rings and a dynamic rubber X'Ring. It follows the bore diameters, in line with the standards MIL-G-5514F and AS4716.

Advantages

Optimal sealing for separating two fluids
Low friction coefficient; no stick-slip effect
Excellent abrasion resistance
Wide temperature range and excellent chemical resistance, depending on the material selected for the O'Rings

Technical data

Temperature

-40°C/+200°C

Pressure

35 MPa

Speed

3 m/s

Medias

Hydraulic fluids with a mineral oil base
Fire retardant hydraulic fluids
Bio oils
Phosphate esters
Water

Applications

Actuators
Brakes systems
Flight controls
Engine systems
Landing gear

Materials

Friction ring

Bronze-filled PTFE
Carbon-filled PTFE
GL Blue PTFE

O'Rings

NBR 70 Shore A
FKM 70 Shore A

X'Ring

NBR 70 Shore A
FKM 70 Shore A

Dimensions
Materials
Technical data

Dimensions

Installation drawingLogement Gorge Joint de piston aéronautique - Housing Groove Gland aerospace piston seal BECA 508S

Materials

Friction ring O'Ring / X'Ring Contact surface area
Standard code ISO code Material Colour Characteristics Code Type of material Service temperature
DP P Virgin PTFE White Resistance to chemical products
Sealing water
Dielectric
Non-stick
Low friction coefficient
Food & Beverage
K6 NBR 70 Shore A -30°C/+100°C Steel
Stainless steel
Chrome steel
Aluminium
Bronze
Cast iron
Treated surface
G6 FKM 70 Shore A -20°C/+200°C
C6 EPDM 70 Shore A -40°C/+145°C
F6 VMQ 70
Shore A
-60°C/+200°C
DC C PTFE
+25% Carbon
Grey

Improvement

  • Wear properties
  • Compression set

Good resistance to chemical products
Thermal and electrical conductivity
Anti-static

Efficient as part of dynamic
applications with compression

K6 NBR 70 Shore A -30°C/+100°C
G6 FKM 70 Shore A -20°C/+200°C
C6 EPDM 70 Shore A -40°C/+145°C
CG C PTFE
+ 23% Carbon
+ 2% Graphite
Black K6 NBR 70 Shore A -30°C/+100°C
G6 FKM 70 Shore A -20°C/+200°C
C6 EPDM 70 Shore A -40°C/+145°C
DV V PTFE
+ 25 % Glass
Blue Improvement
  • Wear properties
  • Mechanical strength
Slightly more abrasive but can be
corrected with the addition of MOS2
Chemical and dielectric properties preserved

Well suited to applications with
rotating and simultaneous alternating movements
K6 NBR 70 Shore A -30°C/+100°C Steel
Chrome steel
Cast iron
G6 FKM 70 Shore A -20°C/+200°C
VM M PTFE
+ 15 % Glass
+ 5% MoS2
Grey K6 NBR 70 Shore A -30°C/+100°C
G6 FKM 70 Shore A -20°C/+200°C
DX X GL Blue PTFE
+ Glass
+ Metal oxides
Turquoise blue Compression resistant
Wear resistant
Excellent chemical stability
Good thermal conductivity
K6 NBR 70 Shore A -30°C/+100°C
G6 FKM 70 Shore A -20°C/+200°C
DG G PTFE
+ 15% Graphite
Black Improvement
  • Wear properties
Reduced wear on metal parts
Self-lubricating
Thermal and electrical conductivity
Low permeability
Good friction coefficient
Anti-static

Efficient as part of dynamic
dynamic applications with self-lubrication
K6 NBR 70 Shore A -30°C/+100°C Steel
Stainless steel
Chrome steel
Aluminium
Bronze
Cast iron
Treated surface
G6 FKM 70 Shore A -20°C/+200°C
C6 EPDM 70 Shore A -40°C/+145°C
K1 K PTFE
+ 10% Ekonol
Light brown Improvement
  • Better abrasion resistance
  • Better dimensional stability at high temperatures
Use up to 300°C
Good friction coefficient and low permeability
K6 NBR 70 Shore A -30°C/+100°C
G6 FKM 70 Shore A -20°C/+200°C
C6 EPDM 70 Shore A -40°C/+145°C
K2 K PTFE
20% Ekonol
Light brown K6 NBR 70 Shore A -30°C/+100°C
G6 FKM 70 Shore A -20°C/+200°C
C6 EPDM 70 Shore A -40°C/+145°C
DB B PTFE
+ 60% Bronze
Dark brown Improvement
  • Wear properties
  • Deformation and creep resistance
  • Compression resistant
Self-lubricating
Electrical and thermal conductivity
Does not alter metal parts
Reduced resistance to certain chemical products

Used for dynamic seals with a strong compression and low level of wear
K6 NBR 70 Shore A -30°C/+100°C Steel
Chrome steel
Cast iron
G6 FKM 70 Shore A -20°C/+200°C
B4 B PTFE
+ 40% Bronze
Dark brown K6 NBR 70 Shore A -30°C/+100°C
G6 FKM 70 Shore A -20°C/+200°C

Other grades of materials are available depending on your specificities.

Technical data

Housing Groove Gland Aerospace Piston Seal - BECA 508S

Groove widths and extrusion gaps

Series Width
L1 min - max
Extrusion gaps
F
O'Ring
Ød2.1
X'Ring
Ød2.2
325 - 329 7.14 - 7.39 0.15 2.62 1.78
330 - 345 0.18
346 - 349 0.20
425 - 445 9.53 - 9.78 0.23 3.53 2.62
446 0.25
447 - 460 0.28

Tolerances on the bore diameters and groove diameters

Series Tolerance on
bore diameter
ØD1
Tolerance on
groove diameter
Ød1
325 - 460 0/+0.050 -0.050/0

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

Radius and chamfers

Series Radius
R1 min - max
Radius
R2 min - max
Chamfer
C
325 - 460 0.13 - 0.26 0.50 - 0.73 5.00
61 dimensions found
508.S325
Standard request
325 47,42 37,97 7,14 128 031
508.S326
Standard request
326 50,60 41,15 7,14 130 032
508.S327
Standard request
327 53,80 44,35 7,14 132 033
508.S328
Standard request
328 56,97 47,52 7,14 133 034
508.S329
Standard request
329 60,15 50,70 7,14 135 035
508.S330
Standard request
330 63,32 53,87 7,14 137 036
508.S331
Standard request
331 66,50 57,05 7,14 139 037
508.S332
Standard request
332 69,67 60,22 7,14 141 038
508.S333
Standard request
333 72,85 63,40 7,14 143 039
508.S334
Standard request
334 76,02 66,57 7,14 145 040
508.S335
Standard request
335 79,20 69,75 7,14 147 041
508.S336
Standard request
336 82,37 72,92 7,14 149 041
508.S337
Standard request
337 85,55 76,10 7,14 151 042
508.S338
Standard request
338 88,72 79,27 7,14 151 042
508.S339
Standard request
339 91,90 82,45 7,14 152 043
508.S340
Standard request
340 95,07 85,62 7,14 152 043
508.S341
Standard request
341 98,25 88,80 7,14 153 044
508.S342
Standard request
342 101,42 91,97 7,14 153 044
508.S343
Standard request
343 104,60 95,15 7,14 154 045
508.S344
Standard request
344 107,77 98,32 7,14 154 045
508.S345
Standard request
345 110,95 101,50 7,14 155 046
508.S346
Standard request
346 114,12 104,67 7,14 155 046
508.S347
Standard request
347 117,30 107,85 7,14 156 047
508.S348
Standard request
348 120,47 111,02 7,14 156 047
508.S349
Standard request
349 123,65 114,20 7,14 157 048
508.S425
Standard request
425 126,34 114,22 9,53 245 158
508.S426
Standard request
426 129,51 117,40 9,53 246 158
508.S427
Standard request
427 132,69 120,57 9,53 247 159
508.S428
Standard request
428 135,86 123,75 9,53 248 159
508.S429
Standard request
429 139,04 126,92 9,53 249 160
508.S430
Standard request
430 142,21 130,10 9,53 250 160
508.S431
Standard request
431 145,39 133,27 9,53 251 161
508.S432
Standard request
432 148,56 136,45 9,53 252 161
508.S433
Standard request
433 151,74 139,62 9,53 253 162
508.S434
Standard request
434 154,91 142,80 9,53 254 162
508.S435
Standard request
435 158,09 145,97 9,53 255 163
508.S436
Standard request
436 161,26 149,15 9,53 256 163
508.S437
Standard request
437 164,44 152,32 9,53 257 164
508.S438
Standard request
438 170,79 158,67 9,53 259 165
508.S439
Standard request
439 177,14 165,02 9,53 259 166
508.S440
Standard request
440 183,49 171,37 9,53 260 167
508.S441
Standard request
441 189,84 177,72 9,53 261 168
508.S442
Standard request
442 196,19 184,07 9,53 262 169
508.S443
Standard request
443 202,54 190,42 9,53 263 170
508.S444
Standard request
444 208,89 196,77 9,53 264 171
508.S445
Standard request
445 215,24 203,12 9,53 265 172
508.S446
Standard request
446 227,94 215,82 9,53 267 174
508.S447
Standard request
447 240,64 228,52 9,53 269 176
508.S448
Standard request
448 253,34 241,22 9,53 271 178
508.S449
Standard request
449 266,04 253,92 9,53 273 179
508.S450
Standard request
450 278,74 266,62 9,53 275 180
508.S451
Standard request
451 291,44 279,32 9,53 276 181
508.S452
Standard request
452 304,14 292,02 9,53 277 182
508.S453
Standard request
453 316,84 304,72 9,53 278 183
508.S454
Standard request
454 329,54 317,42 9,53 278 184
508.S455
Standard request
455 342,24 330,12 9,53 279 185
508.S456
Standard request
456 354,94 342,82 9,53 279 186
508.S457
Standard request
457 367,64 355,52 9,53 280 187
508.S458
Standard request
458 380,34 368,22 9,53 280 188
508.S459
Standard request
459 393,04 380,92 9,53 281 189
508.S460
Standard request
460 405,74 393,62 9,53 281 190