BK2
Metal Bellows Coupling with clamping hub

15 - 10,000 Nm

BK2 METAL BELLOWS COUPLING WITH CLAMPING HUB

BK2

Specifications BK2

BK2 Series
Rated torque (Nm)TKN
Overall length (mm)A-2
Fit length (mm)C
Inside diameter possible from Ø to Ø H7 (mm)
D1/D2
Outside diameter (mm)B
Moment of inertia (10-3 kgm2)Jges.
Approximate weight (kg)
Torsional stiffness (10³ Nm/rad)CT
Axial ± (mm))max.
Lateral ± (mm)max.
Angular ± (degree)max.
Axial spring stiffness (N/mm)Ca
Lateral spring stiffness (N/mm)Cr
Fastening screw ISO 4762E
Tightening torque of the fastening screw (Nm)E
Distance between centerlines (mm)F
Distance (mm)G
Hub material
CAD Portal
BK2 Serien15
Rated torque (Nm)TKN15
Overall length (mm)A-259 | 66 | 99
Fit length (mm)C22
Inside diameter possible from Ø to Ø H7 (mm)
D1/D28-28
Outside diameter (mm)B49
Moment of inertia (10-3 kgm2)Jges.0,06 | 0,07 | 0,08
Approximate weight (kg)0,16
Torsional stiffness (10³ Nm/rad)CT20 | 15 | 14
Axial ± (mm))max.1 | 2 | 3
Lateral ± (mm)max.0,15 | 0,2 | 1
Angular ± (degree)max.1|1,5|2
Axial spring stiffness (N/mm)Ca25 | 15 |84
Lateral spring stiffness (N/mm)Cr475 | 137 | 140
Fastening screw ISO 4762EM5
Tightening torque of the fastening screw (Nm)E8
Distance between centerlines (mm)F17
Distance (mm)G6,5
Hub materialAluminium
optional Steel
15
CAD
BK2 Series
Rated torque (Nm)TKN
Overall length (mm)A-2
Fit length (mm)C
Inside diameter possible from Ø to Ø H7 (mm)
D1/D2
Outside diameter (mm)B
Moment of inertia (10-3 kgm2)Jges.
Approximate weight (kg)
Torsional stiffness (10³ Nm/rad)CT
Axial ± (mm))max.
Lateral ± (mm)max.
Angular ± (degree)max.
Axial spring stiffness (N/mm)Ca
Lateral spring stiffness (N/mm)Cr
Fastening screw ISO 4762E
Tightening torque of the fastening screw (Nm)E
Distance between centerlines (mm)F
Distance (mm)G
Hub material
CAD Portal
BK2 Serien30
Rated torque (Nm)TKN30
Overall length (mm)A-269 | 77 | 113
Fit length (mm)C27
Inside diameter possible from Ø to Ø H7 (mm)
D1/D210-30
Outside diameter (mm)B55
Moment of inertia (10-3 kgm2)Jges.0,12 | 0,13 | 0,14
Approximate weight (kg)0,26
Torsional stiffness (10³ Nm/rad)CT39 | 28 | 27
Axial ± (mm))max.1 | 2 |3
Lateral ± (mm)max.0,2 | 0,25 | 1
Angular ± (degree)max.1|1,5|2
Axial spring stiffness (N/mm)Ca50 | 30 | 118
Lateral spring stiffness (N/mm)Cr900 | 270 | 224
Fastening screw ISO 4762EM6
Tightening torque of the fastening screw (Nm)E15
Distance between centerlines (mm)F19
Distance (mm)G7,5
Hub materialAluminium
optional Steel
30
CAD
BK2 Series
Rated torque (Nm)TKN
Overall length (mm)A-2
Fit length (mm)C
Inside diameter possible from Ø to Ø H7 (mm)
D1/D2
Outside diameter (mm)B
Moment of inertia (10-3 kgm2)Jges.
Approximate weight (kg)
Torsional stiffness (10³ Nm/rad)CT
Axial ± (mm))max.
Lateral ± (mm)max.
Angular ± (degree)max.
Axial spring stiffness (N/mm)Ca
Lateral spring stiffness (N/mm)Cr
Fastening screw ISO 4762E
Tightening torque of the fastening screw (Nm)E
Distance between centerlines (mm)F
Distance (mm)G
Hub material
CAD Portal
BK2 Serien60
Rated torque (Nm)TKN60
Overall length (mm)A-283 | 93 |130
Fit length (mm)C31
Inside diameter possible from Ø to Ø H7 (mm)
D1/D212-35
Outside diameter (mm)B66
Moment of inertia (10-3 kgm2)Jges.0,32 | 0,35 | 0,4
Approximate weight (kg)0,48
Torsional stiffness (10³ Nm/rad)CT76 | 55 | 54
Axial ± (mm))max.1,5 | 2 | 3
Lateral ± (mm)max.0,2 | 0,25 | 1
Angular ± (degree)max.1|1,5|2
Axial spring stiffness (N/mm)Ca72 | 48 | 165
Lateral spring stiffness (N/mm)Cr1200 | 420 | 337
Fastening screw ISO 4762EM8
Tightening torque of the fastening screw (Nm)E40
Distance between centerlines (mm)F23
Distance (mm)G9,5
Hub materialAluminium
optional Steel
60
CAD
BK2 Series
Rated torque (Nm)TKN
Overall length (mm)A-2
Fit length (mm)C
Inside diameter possible from Ø to Ø H7 (mm)
D1/D2
Outside diameter (mm)B
Moment of inertia (10-3 kgm2)Jges.
Approximate weight (kg)
Torsional stiffness (10³ Nm/rad)CT
Axial ± (mm))max.
Lateral ± (mm)max.
Angular ± (degree)max.
Axial spring stiffness (N/mm)Ca
Lateral spring stiffness (N/mm)Cr
Fastening screw ISO 4762E
Tightening torque of the fastening screw (Nm)E
Distance between centerlines (mm)F
Distance (mm)G
Hub material
CAD Portal
BK2 Serien80
Rated torque (Nm)TKN80
Overall length (mm)A-294 | 106 | 143
Fit length (mm)C36
Inside diameter possible from Ø to Ø H7 (mm)
D1/D214-42
Outside diameter (mm)B81
Moment of inertia (10-3 kgm2)Jges.0,8 | 0,85 | 0,9
Approximate weight (kg)0,8
Torsional stiffness (10³ Nm/rad)CT129 | 85 | 84
Axial ± (mm))max.2 | 3 | 4
Lateral ± (mm)max.0,2 | 0,25 | 1
Angular ± (degree)max.1|1,5|2
Axial spring stiffness (N/mm)Ca48 | 32 | 144
Lateral spring stiffness (N/mm)Cr920 | 290 | 401
Fastening screw ISO 4762EM10
Tightening torque of the fastening screw (Nm)E50
Distance between centerlines (mm)F27
Distance (mm)G11
Hub materialAluminium
optional Steel
80
CAD
BK2 Series
Rated torque (Nm)TKN
Overall length (mm)A-2
Fit length (mm)C
Inside diameter possible from Ø to Ø H7 (mm)
D1/D2
Outside diameter (mm)B
Moment of inertia (10-3 kgm2)Jges.
Approximate weight (kg)
Torsional stiffness (10³ Nm/rad)CT
Axial ± (mm))max.
Lateral ± (mm)max.
Angular ± (degree)max.
Axial spring stiffness (N/mm)Ca
Lateral spring stiffness (N/mm)Cr
Fastening screw ISO 4762E
Tightening torque of the fastening screw (Nm)E
Distance between centerlines (mm)F
Distance (mm)G
Hub material
CAD Portal
BK2 Serien150
Rated torque (Nm)TKN150
Overall length (mm)A-295 | 107 | 144
Fit length (mm)C36
Inside diameter possible from Ø to Ø H7 (mm)
D1/D219-42
Outside diameter (mm)B81
Moment of inertia (10-3 kgm2)Jges.1,9 | 2 | 2,1
Approximate weight (kg)1,85
Torsional stiffness (10³ Nm/rad)CT175 | 110 | 97
Axial ± (mm))max.2 | 3 | 4
Lateral ± (mm)max.0,2 | 0,25 | 1
Angular ± (degree)max.1|1,5|2
Axial spring stiffness (N/mm)Ca82 | 52 | 130
Lateral spring stiffness (N/mm)Cr1550 | 435 | 500
Fastening screw ISO 4762EM10
Tightening torque of the fastening screw (Nm)E70
Distance between centerlines (mm)F27
Distance (mm)G11
Hub materialSteel
optional Aluminium
150
CAD
BK2 Series
Rated torque (Nm)TKN
Overall length (mm)A-2
Fit length (mm)C
Inside diameter possible from Ø to Ø H7 (mm)
D1/D2
Outside diameter (mm)B
Moment of inertia (10-3 kgm2)Jges.
Approximate weight (kg)
Torsional stiffness (10³ Nm/rad)CT
Axial ± (mm))max.
Lateral ± (mm)max.
Angular ± (degree)max.
Axial spring stiffness (N/mm)Ca
Lateral spring stiffness (N/mm)Cr
Fastening screw ISO 4762E
Tightening torque of the fastening screw (Nm)E
Distance between centerlines (mm)F
Distance (mm)G
Hub material
CAD Portal
BK2 Serien200
Rated torque (Nm)TKN200
Overall length (mm)A-2105 | 117 | 163
Fit length (mm)C41
Inside diameter possible from Ø to Ø H7 (mm)
D1/D222-45
Outside diameter (mm)B90
Moment of inertia (10-3 kgm2)Jges.3,2 | 3,4 | 3,6
Approximate weight (kg)2,65
Torsional stiffness (10³ Nm/rad)CT191 | 140 | 135
Axial ± (mm))max.2 | 3 | 4
Lateral ± (mm)max.0,25 | 0,3 | 1
Angular ± (degree)max.1|1,5|2
Axial spring stiffness (N/mm)Ca90 | 60 | 280
Lateral spring stiffness (N/mm)Cr2040 | 610 | 750
Fastening screw ISO 4762EM12
Tightening torque of the fastening screw (Nm)E120
Distance between centerlines (mm)F31
Distance (mm)G12,5
Hub materialSteel
optional Aluminium
200
CAD
BK2 Series
Rated torque (Nm)TKN
Overall length (mm)A-2
Fit length (mm)C
Inside diameter possible from Ø to Ø H7 (mm)
D1/D2
Outside diameter (mm)B
Moment of inertia (10-3 kgm2)Jges.
Approximate weight (kg)
Torsional stiffness (10³ Nm/rad)CT
Axial ± (mm))max.
Lateral ± (mm)max.
Angular ± (degree)max.
Axial spring stiffness (N/mm)Ca
Lateral spring stiffness (N/mm)Cr
Fastening screw ISO 4762E
Tightening torque of the fastening screw (Nm)E
Distance between centerlines (mm)F
Distance (mm)G
Hub material
CAD Portal
BK2 Serien300
Rated torque (Nm)TKN300
Overall length (mm)A-2111 | 125 | 200
Fit length (mm)C43
Inside diameter possible from Ø to Ø H7 (mm)
D1/D224-60
Outside diameter (mm)B110
Moment of inertia (10-3 kgm2)Jges.7,6 | 7,9 | 8,3
Approximate weight (kg)4
Torsional stiffness (10³ Nm/rad)CT450 | 350 | 340
Axial ± (mm))max.2,5 | 3,5 | 4,5
Lateral ± (mm)max.0,25 | 0,3 | 1
Angular ± (degree)max.1|1,5|2
Axial spring stiffness (N/mm)Ca105 | 71 | 605
Lateral spring stiffness (N/mm)Cr3750 | 1050 | 1200
Fastening screw ISO 4762EM12
Tightening torque of the fastening screw (Nm)E130
Distance between centerlines (mm)F39
Distance (mm)G13
Hub materialSteel
optional Aluminium
300
CAD
BK2 Series
Rated torque (Nm)TKN
Overall length (mm)A-2
Fit length (mm)C
Inside diameter possible from Ø to Ø H7 (mm)
D1/D2
Outside diameter (mm)B
Moment of inertia (10-3 kgm2)Jges.
Approximate weight (kg)
Torsional stiffness (10³ Nm/rad)CT
Axial ± (mm))max.
Lateral ± (mm)max.
Angular ± (degree)max.
Axial spring stiffness (N/mm)Ca
Lateral spring stiffness (N/mm)Cr
Fastening screw ISO 4762E
Tightening torque of the fastening screw (Nm)E
Distance between centerlines (mm)F
Distance (mm)G
Hub material
CAD Portal
BK2 Serien500
Rated torque (Nm)TKN500
Overall length (mm)A-2133 | 146 | 169
Fit length (mm)C51
Inside diameter possible from Ø to Ø H7 (mm)
D1/D235-60
Outside diameter (mm)B124
Moment of inertia (10-3 kgm2)Jges.14,3 | 14,6 | 14,8
Approximate weight (kg)6,3
Torsional stiffness (10³ Nm/rad)CT510 | 500 | 400
Axial ± (mm))max.2,5 | 3,5 | 4,5
Lateral ± (mm)max.0,3 | 0,35 | 1
Angular ± (degree)max.1|1,5|2
Axial spring stiffness (N/mm)Ca70 | 48 | 85
Lateral spring stiffness (N/mm)Cr2500 | 840 | 614
Fastening screw ISO 4762EM16
Tightening torque of the fastening screw (Nm)E200
Distance between centerlines (mm)F41
Distance (mm)G16,5
Hub materialSteel
optional Aluminium
500
CAD
BK2 Series
Rated torque (Nm)TKN
Overall length (mm)A-2
Fit length (mm)C
Inside diameter possible from Ø to Ø H7 (mm)
D1/D2
Outside diameter (mm)B
Moment of inertia (10-3 kgm2)Jges.
Approximate weight (kg)
Torsional stiffness (10³ Nm/rad)CT
Axial ± (mm))max.
Lateral ± (mm)max.
Angular ± (degree)max.
Axial spring stiffness (N/mm)Ca
Lateral spring stiffness (N/mm)Cr
Fastening screw ISO 4762E
Tightening torque of the fastening screw (Nm)E
Distance between centerlines (mm)F
Distance (mm)G
Hub material
CAD Portal
BK2 Serien800
Rated torque (Nm)TKN800
Overall length (mm)A-2140 | 179
Fit length (mm)C45
Inside diameter possible from Ø to Ø H7 (mm)
D1/D240-75
Outside diameter (mm)B134
Moment of inertia (10-3 kgm2)Jges.16,2 | 17
Approximate weight (kg)5,7
Torsional stiffness (10³ Nm/rad)CT780 | 711
Axial ± (mm))max.3,5 | 4,5
Lateral ± (mm)max.0,35 | 1
Angular ± (degree)max.1,5 | 2
Axial spring stiffness (N/mm)Ca100 | 285
Lateral spring stiffness (N/mm)Cr2000 | 1490
Fastening screw ISO 4762E2x M16*
Tightening torque of the fastening screw (Nm)E250
Distance between centerlines (mm)F2x48
Distance (mm)G18
Hub materialSteel
800
CAD
BK2 Series
Rated torque (Nm)TKN
Overall length (mm)A-2
Fit length (mm)C
Inside diameter possible from Ø to Ø H7 (mm)
D1/D2
Outside diameter (mm)B
Moment of inertia (10-3 kgm2)Jges.
Approximate weight (kg)
Torsional stiffness (10³ Nm/rad)CT
Axial ± (mm))max.
Lateral ± (mm)max.
Angular ± (degree)max.
Axial spring stiffness (N/mm)Ca
Lateral spring stiffness (N/mm)Cr
Fastening screw ISO 4762E
Tightening torque of the fastening screw (Nm)E
Distance between centerlines (mm)F
Distance (mm)G
Hub material
CAD Portal
BK2 Serien1500
Rated torque (Nm)TKN1500
Overall length (mm)A-2166 | 230
Fit length (mm)C55
Inside diameter possible from Ø to Ø H7 (mm)
D1/D250-80
Outside diameter (mm)B157
Moment of inertia (10-3 kgm2)Jges.43 | 45
Approximate weight (kg)11,5
Torsional stiffness (10³ Nm/rad)CT1304 | 1180
Axial ± (mm))max.3,5 | 4,5
Lateral ± (mm)max.0,35 | 1
Angular ± (degree)max.1,5 | 2
Axial spring stiffness (N/mm)Ca320 | 440
Lateral spring stiffness (N/mm)Cr3600 | 1700
Fastening screw ISO 4762E2x M20*
Tightening torque of the fastening screw (Nm)E470
Distance between centerlines (mm)F2x55
Distance (mm)G22,5
Hub materialSteel
1500
CAD
BK2 Series
Rated torque (Nm)TKN
Overall length (mm)A-2
Fit length (mm)C
Inside diameter possible from Ø to Ø H7 (mm)
D1/D2
Outside diameter (mm)B
Moment of inertia (10-3 kgm2)Jges.
Approximate weight (kg)
Torsional stiffness (10³ Nm/rad)CT
Axial ± (mm))max.
Lateral ± (mm)max.
Angular ± (degree)max.
Axial spring stiffness (N/mm)Ca
Lateral spring stiffness (N/mm)Cr
Fastening screw ISO 4762E
Tightening torque of the fastening screw (Nm)E
Distance between centerlines (mm)F
Distance (mm)G
Hub material
CAD Portal
BK2 Serien4000
Rated torque (Nm)TKN4000
Overall length (mm)A-2225
Fit length (mm)C85
Inside diameter possible from Ø to Ø H7 (mm)
D1/D250-90
Outside diameter (mm)B200
Moment of inertia (10-3 kgm2)Jges.165
Approximate weight (kg)28,8
Torsional stiffness (10³ Nm/rad)CT3400
Axial ± (mm))max.3,5
Lateral ± (mm)max.0,4
Angular ± (degree)max.1,5
Axial spring stiffness (N/mm)Ca565
Lateral spring stiffness (N/mm)Cr6070
Fastening screw ISO 4762E2x M24*
Tightening torque of the fastening screw (Nm)E1200
Distance between centerlines (mm)F2x65
Distance (mm)G28
Hub materialSteel
4000
CAD
BK2 Series
Rated torque (Nm)TKN
Overall length (mm)A-2
Fit length (mm)C
Inside diameter possible from Ø to Ø H7 (mm)
D1/D2
Outside diameter (mm)B
Moment of inertia (10-3 kgm2)Jges.
Approximate weight (kg)
Torsional stiffness (10³ Nm/rad)CT
Axial ± (mm))max.
Lateral ± (mm)max.
Angular ± (degree)max.
Axial spring stiffness (N/mm)Ca
Lateral spring stiffness (N/mm)Cr
Fastening screw ISO 4762E
Tightening torque of the fastening screw (Nm)E
Distance between centerlines (mm)F
Distance (mm)G
Hub material
CAD Portal
BK2 Serien6000
Rated torque (Nm)TKN6000
Overall length (mm)A-2252
Fit length (mm)C107
Inside diameter possible from Ø to Ø H7 (mm)
D1/D260-140
Outside diameter (mm)B253
Moment of inertia (10-3 kgm2)Jges.495
Approximate weight (kg)49,4
Torsional stiffness (10³ Nm/rad)CT5700
Axial ± (mm))max.3
Lateral ± (mm)max.0,4
Angular ± (degree)max.1,5
Axial spring stiffness (N/mm)Ca1030
Lateral spring stiffness (N/mm)Cr19200
Fastening screw ISO 4762E2x M24*
Tightening torque of the fastening screw (Nm)E1200
Distance between centerlines (mm)F2x90
Distance (mm)G35
Hub materialSteel
6000
CAD
BK2 Series
Rated torque (Nm)TKN
Overall length (mm)A-2
Fit length (mm)C
Inside diameter possible from Ø to Ø H7 (mm)
D1/D2
Outside diameter (mm)B
Moment of inertia (10-3 kgm2)Jges.
Approximate weight (kg)
Torsional stiffness (10³ Nm/rad)CT
Axial ± (mm))max.
Lateral ± (mm)max.
Angular ± (degree)max.
Axial spring stiffness (N/mm)Ca
Lateral spring stiffness (N/mm)Cr
Fastening screw ISO 4762E
Tightening torque of the fastening screw (Nm)E
Distance between centerlines (mm)F
Distance (mm)G
Hub material
CAD Portal
BK2 Serien10000
Rated torque (Nm)TKN10000
Overall length (mm)A-2288
Fit length (mm)C129
Inside diameter possible from Ø to Ø H7 (mm)
D1/D270-180
Outside diameter (mm)B303
Moment of inertia (10-3 kgm2)Jges.1214
Approximate weight (kg)80,9
Torsional stiffness (10³ Nm/rad)CT10950
Axial ± (mm))max.3
Lateral ± (mm)max.0,4
Angular ± (degree)max.1,5
Axial spring stiffness (N/mm)Ca985
Lateral spring stiffness (N/mm)Cr21800
Fastening screw ISO 4762E2x M30*
Tightening torque of the fastening screw (Nm)E2400
Distance between centerlines (mm)F2x117
Distance (mm)G42
Hub materialSteel
10000
CAD

Properties

  • Design:
    • With a single radial clamping screw per hub ISO 4762.
    • Any imbalance of the clamping hubs is compensated for by balancing bores located on the inside of the hub.
  • Temperature range: -30° C bis +100° C (-22° F to +212° F)
  • Backlash: Absolutely backlash-free due to frictional clamp connection.
  • Service life: These couplings are maintenance-free if the technical ratings are not exceeded.
  • Tolerance: On the hub/shaft connection 0.01 to 0.05 mm.
  • Material:
    • Bellows made of highly flexible high-grade stainless steel.
    • Hub material: see table below.
  • Brief overloads: Acceptable up to 1.5 times the value specified.
  • Speeds: Up to 10,000 rpm, in excess of 10,000 available with a finely balanced version.
  • Non-standard application: Custom designs with varied tolerances, keyways, non-standard material, bellows and ATEX designs are available upon request.
  • Properties of Bellows Coupling model BK2:
    • easy to mount
    • suited for space restricted installations
    • low moment of inertia


Overview