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BECA 845 - 847

BECA 845 - 847
BECA 845 - 847
beca_845_3d_v1
beca_845_3d_v2

Description

The BECA 845 - 847 roto seals are single or double acting piston rotary seals composed of a filled PTFE grooved friction ring and two pre-tightened rubber O'Rings.

Advantages

Low friction coefficient; no stick-slip effect on start up
Excellent abrasion and extrusion resistance
The grooves provide an integrated lubrication system
Excellent dimensional stability

Technical data

Temperature

-30°C/+200°C

Pressure

30 MPa

Speed

2 m/s

Medias

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

Applications

Rotary distributors
Handlers
Hydraulic motors

Materials

Friction ring

Bronze-filled PTFE
Carbon-filled PTFE
Virgin PTFE

O'Rings

NBR 70 Shore A
FKM 70 Shore A

Dimensions
Installation dimensions
Materials
Technical data

Dimensions

Installation drawingLogement Gorge Rotojoint de piston - Housing Groove Piston rotoseal - BECA 845 - 847

Installation dimensions

Housing Groove Piston Rotoseal - BECA 845 - 847

Installation dimensions

Bore diameter
ØD1 H9
Groove diameter
Ød1 h9
Groove width O'Ring
cross-section
BECA 847 Standard
series
BECA 845 Heavy-duty
series
s (m/s) < 0.2
p (MPa) < 2.5
0.2 < v (m/s) < 0.5
2.5 < p (MPa) < 5.0
0.5 < v (m/s) < 1.0
5.0 < p (MPa) < 25.0
1.0 < v (m/s) < 2.0
25.0 < p (MPa) < 40.0
2.0 < v (m/s) < 5.0
40.0 < p (MPa) < 50.0
L1 0/+0.20 Ød2
8.0 - 39.9 --- D1 - 4.20 D1 - 4.40 D1 - 4.50 D1 - 4.60 D1 - 4.70 4.30 1.78
40.0 - 79.9 14.0 - 39.9 D1 - 6.20 D1 - 6.40 D1 - 6.60 D1 - 6.80 D1 - 6.90 6.30 2.62
80.0 - 132.9 40.0 - 79.9 D1 - 8.40 D1 - 8.60 D1 - 8.90 D1 - 9.10 D1 - 9.30 8.50 3.53
133.0 - 329.9 80.0 - 132.9 D1 - 12.70 D1 - 13.00 D1 - 13.40 D1 - 13.80 D1 - 14.00 12.90 5.33
330.0 - 669.9 133.0 - 329.9 D1 - 16.60 D1 - 17.00 D1 - 17.50 D1 - 18.00 D1 - 18.30 16.90 6.99

For special applications > 20 MPa, we recommend using an H8/f8 tolerance (bore/groove) or selecting other more suitable materials. Please contact our experts.

Materials

Friction ring O'Rings 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 -45°C/+150°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 -45°C/+150°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 -45°C/+150°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
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 -45°C/+150°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

Other grades of materials are available depending on your specificities.

Technical data

Housing Groove Piston Rotoseal - BECA 845 - 847

Extrusion gaps

Radial section
S
Radial extrusion gap
F/2
10 MPa 20 MPa 20 MPa
2.45 0.15 0.10 0.05
3.75 0.20 0.15 0.10
5.50 0.25 0.20 0.15
7.75 0.30 0.25 0.20
10.50 0.30 0.25 0.20
14.00 0.45 0.30 0.25

Surface roughness

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

Chamfers and radius

Radial section
S
Radius
R1
Radius
R2
Chamfer
C
2.45 0.20 0.40 2.00
3.75 0.20 0.60 2.50
5.50 0.20 1.00 3.50
7.75 0.20 1.30 5.00
10.50 0.20 1.80 6.50
14.00 0.20 2.50 17.50

Only on request