BECA 508S

Aerospace seals / Piston seals

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

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Product data - Aerospace piston seal - BECA 508S

Series	Bore diameter	Groove diameter	Groove width	O'Ring Series	X'Ring Series
AS4716 / MIL-G-5514
ØD1	Ød1	L1 min

Dimensions

Materials

Technical data

Dimensions

Installation drawing Logement 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	Contact surface area
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
DV	V	PTFE + 25 % Glass	Blue		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
VM	M	PTFE + 15 % Glass + 5% MoS2	Grey		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
DX	X	GL Blue PTFE + Glass + Metal oxides	Turquoise blue		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
DB	B	PTFE + 60% Bronze	Dark brown		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
B4	B	PTFE + 40% Bronze	Dark brown		G6	FKM 70 Shore A	-20°C/+200°C

Other grades of materials are available depending on your specificities.

Technical data

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

Only on request