BECA 655

BECA 655
beca_655_3d_v1
beca_655_3d_v2

Description

The BECA 655 profile is a double acting composite piston seal composed of a profiled rubber ring and a polyamide or POM friction ring with a step cut.

Advantages

The square ring does not twist
Low friction coefficient
Excellent extrusion resistance
Compatible with hydraulic oils

Technical data

Temperature

-30°C/+100°C

Pressure

50 MPa

Speed

0.5 m/s

Medias

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

Applications

Agriculture
Mobile machinery
Hydraulic cylinders

Materials

Friction ring

Polyamide PA6
Polyoxymethylene (POM)

Profiled seal

NBR 70 Shore A

Dimensions
Installation dimensions
Materials
Technical data

Dimensions

Installation drawingLogement Gorge Joint de piston - Housing Groove Gland Piston seal BECA 655

Installation dimensions

Housing Groove Gland Piston Seal - BECA - 655

Installation dimensions

Groove diameter Groove width Radial section
Ød1 h9 L1 0/+0.20 S
D1 - 11.00 4.20 5.50
D1 - 15.50 6.30 7.75
D1 - 21.00 8.10 10.50

For special applications > 40 MPa, we recommend using an H8/f8 tolerance (bore/piston) or selecting other more suitable materials. Please contact our experts.

Materials

Polyamide - PA6G

There are different types of polyamides, more commonly known as "nylons". The most important are: PA 6, PA 66, PA 11 and PA 12. These types of nylons have different physical properties, mainly their composition and the structure of their molecular chains.
The PA6G polyamide is characterised by its stiffness, strong sliding abilities, excellent machinability and excellent resistance to wear and abrasion.

Advantages Good mechanical resistance, stiffness, hardness and resilience
Good fatigue resistance
Strong shock absorbing potential
Good sliding properties
Excellent wear resistance
Good electrical insulation properties
Good resistance to high-energy radiation
Good machinability
Limits Dimensional stability is not as good as POM
Temperature range -30°C / +120°C (very short term peak at 180°C)

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

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

Technical data

Housing Groove Gland Piston Seal - BECA - 655

Extrusion gaps

Pressure
MPa
Radial extrusion gap
F/2
20 MPa 0.25
35 MPa 0.20
40 MPa 0.15
50 MPa 0.10

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

Radial section
S
Radius
R1
Radius
R2
Chamfer
C
5.50 0.30 0.50 3.00
7.75 0.30 0.90 4.00
10.50 0.30 0.90 5.00
19 dimensions found
655.070HCK6
Standard request
70,00 49,00 8,10
655.075HCK6
Standard request
75,00 54,00 8,10
655.080HCK6
Standard request
80,00 59,00 8,10
655.085HCK6
Standard request
85,00 64,00 8,10
655.090HCK6
Standard request
90,00 69,00 8,10
655.095HCK6
Standard request
95,00 74,00 8,10
655.100HCK6
Standard request
100,00 79,00 8,10
655.105HCK6
Standard request
105,00 84,00 8,10
655.110HCK6
Standard request
110,00 89,00 8,10
655.115HCK6
Standard request
115,00 94,00 8,10
655.120HCK6
Standard request
120,00 99,00 8,10
655.125HCK6
Standard request
125,00 104,00 8,10
655.130HCK6
Standard request
130,00 109,00 8,10
655.140HCK6
Standard request
140,00 119,00 8,10
655.150HCK6
Standard request
150,00 129,00 8,10
655.160HCK6
Standard request
160,00 139,00 8,10
655.170HCK6
Standard request
170,00 149,00 8,10
655.180HCK6
Standard request
180,00 159,00 8,10
655.190HCK6
Standard request
190,00 169,00 8,10