Bearings

Tandwiel lagersRoller bearings are divided into radial bearings and axial bearings for radial and axial loads and some other bearing types that are meant for combined radial and axial loads. In general, ball bearings are meant for low to medium high loads, while roller bearings are designed for high loads. In radial load the force is perpendicular to the axis, whereas with axial load the force works in the longitudinal direction of the axis. At a combined load an axial and radial load occur at the same time. It is of the utmost importance that for each application the right type and the right size of a bearing is chosen.

The following is a choice matrix. This matrix can only serve as a rough guideline, so that a more qualified selection is required for each specific application. Not only the bearing choice is important for a proper operation, but also a good mounting is essential. The dimensions of shaft-and bearing house surfaces, distance tubes etc. must give sufficient support to the bearings. The rotating parts of the bearing must not come into contact with stationary parts. The correct building dimensions for each bearing can be found in the bearing tables. The table below indicates the correct measurements for the relief grooves. The stress distribution of a shaft with changing diameters is more favourable as the rounding of the transition of diameters is larger. In heavily loaded shafts usually a large rounding is required. The chamfer dimensions in radial direction (r1, r3) and axial direction (r2, r4) in the bearing tables are the prescribed minimum dimensions according to IS0 582-1979, i.e. there are no longer given nominal dimenstions. Appropriate maximum chamfer dimensions, which are important in the calculation of the radius of the distance tube, can be found in the tables under “Limits for chamfer dimensions”.

Relief grooves
Chamfer Dimensions of relief grooves
rs min ba ha rc
mm inch mm inch mm inch mm inch
11
1,1
1,5
2
2,1
3
4
5
6
7,5
0,039
0,043
0,059
0,079
0,083
0,118
0,157
0,197
0,236
0,295
2
2,4
3,2
4
4
4,7
5,9
7,4
8,6
10
0,079
0,095
0,126
0,157
0,157
0,185
0,232
0,291
0,339
0,394
0,2
0,3
0,4
0,5
0,5
0,5
0,5
0,6
0,6
0,6
0,008
0,012
0,016
0,020
0,020
0,020
0,020
0,024
0,024
0,024
1,3
1,5
2
2,5
2,5
3
4
5
6
7
0,051
0,059
0,079
0,098
0,098
0,118
0,157
0,197
0,236
0,276

The following tables present you all information for a proper mounting of your bearings.

Bearing type Fits for massive axes in steel and rotating load for the inner ring Fits for bearing houses of steel from of cast iron and stagnant load on the outer ring
Shaft diameters Bearing arrangement Bearing house
<18 18 <40 40 <100 100 <140 140 <200 200 <280 280 <500 >500 <300 300 <500 >500
Groove ball bearings j5 k5 k5 k6 k6 m6 m6 m6 Fixed bearing J6 J6 H7
One row angular contact ball bearings with clearance arrangement at the outer ring j6 k6 k6 m6 m6 n6 p6 p6 Loose bearing G6 G7 F7
Double row and paired angular contact ball bearings 32A/33A 72BECB73B j5 k5 k5 m5 m5 m5 Thrust bearing J6 J6 H7
33E k5 m5 m5 Fixed bearing J6 J6 H7
Four point ball bearing k5 k5 m5 m5 n6 Fixed bearing J6 J6 H7
One row cylindrical roller bearings N,NU,NJ k5 k5 m5 m5 n6 p6 p6 r6 Axial bearing Ensure 1 mm clearance against rotation
Double row spherical roller bearing k5 k5 m5 m5 n6 p6 p6 r6 Fixed bearing J6 J6 H7
Loose bearing G6 G7 F7
Taperd roller bearings with clearance arrangement at the outer ring k6 k6 m6 m6 n6 p6 p6 Thrust bearing J6 J6 H7
Two row and paired ball bearings k5 k5 m5 m5 n6 p6 p6 r6 Fixed bearing J6 J6 H7
Axial ball bearings h6 h6 h6 h6 h6 g6 g6 g6 Axial bearing G7 G7 F7
Spherical roller thrust bearings j6 j6 j6 j6 j6 j6 j6 j6 Axial bearing 1 mm clearance
Shape tolerances Allowed roundness Allowed squareness Allowed conicity across the width of the bearing Allowed surface roughness
At rotating load IT5/2 IT5 As: Ra = 0,8
At stagnating load IT6/2 IT6 IT6 Huis: Ra = 3,2
Mounting of double-row spherical roller bearings with a conical bore

Mounting of double-row spherical roller bearings with a conical bore

Bearing bore d in mm Reduction of radial bearing clearance in mm Axial displacement in mm Smallest end clearance after mounting with starting clearance in mm conicity
Conicity 1:12 Conicity 1:30
from up to min max min max min max Normal C3 C4
24
30
40
50
65
80
100
120
140
160
180
200
225
250
280
315
355
400
450
500
560
630
710
800
900
1000
1120
30
40
50
65
80
100
120
140
160
180
200
225
250
280
315
355
400
450
500
560
630
710
800
900
1000
1120
1250
0,015
0,020
0,025
0,030
0,040
0,045
0,050
0,065
0,075
0,080
0,090
0,100
0,110
0,120
0,130
0,150
0,170
0,200
0,210
0,240
0,260
0,300
0,340
0,370
0,410
0,450
0,490
0,020
0,025
0,030
0,040
0,050
0,060
0,070
0,090
0,100
0,110
0,130
0,140
0,150
0,170
0,190
0,210
0,230
0,260
0,280
0,320
0,350
0,400
0,450
0,500
0,550
0,600
0,650
0,3
0,35
0,40
0,45
0,6
0,7
0,75
1,1
1,2
1,3
1,4
1,6
1,7
1,9
2,0
2,4
2,6
3,1
3,3
3,7
4,0
4,6
5,3
5,7
6,3
6,8
7,4
0,35
0,4
0,45
0,6
0,75
0,9
1,1
1,4
1,6
1,7
2,0
2,2
2,4
2,7
3,0
3,3
3,6
4,0
4,4
5,0
5,4
6,2
7,0
7,8
8,5
9,0
9,8





1,7
1,9
2,7
3,0
3,2
3,5
4,0
4,2
4,7
5,0
6,0
6,5
7,7
8,2
9,2
10
11,5
13,3
14,3
15,8
17
18,5





2,2
2,7
3,5
4,0
4,2
5,0
5,5
6,0
6,7
7,5
8,2
9,0
10
11
12,5
13,5
15,5
17,5
19,5
21
23
25
0,015
0,015
0,020
0,025
0,025
0,035
0,050
0,055
0,055
0,060
0,070
0,080
0,090
0,100
0,110
0,120
0,130
0,130
0,160
0,170
0,200
0,210
0,230
0,270
0,300
0,320
0,340
0,020
0,025
0,030
0,035
0,040
0,050
0,065
0,080
0,090
0,100
0,100
0,120
0,130
0,140
0,150
0,170
0,190
0,200
0,230
0,250
0,290
0,310
0,350
0,390
0,430
0,480
0,540
0,035
0,040
0,050
0,055
0,070
0,080
0,100
0,110
0,130
0,150
0,160
0,180
0,200
0,220
0,240
0,260
0,290
0,310
0,350
0,360
0,410
0,450
0,510
0,570
0,640
0,700
0,770

Axial bearing clearance of a one row angular contact bearings series 72BE and 73 paired in O of X setting

Bore d in mm Axial clearance in mm
CA CB CC
from up to min max min max min max

10
18
30
50
80
120
180
250
10
18
30
50
80
120
180
250
315
4
5
7
9
11
14
17
21
26
12
13
15
17
23
26
29
37
42
14
15
18
22
26
32
35
45
52
22
23
26
30
38
44
47
61
68
22
24
32
40
48
55
62
74
90
30
32
40
48
60
67
74
90
106

Pre stress of one row angular contact bearings series 72BE and 73 paired in O of X setting

Bore in mm Pre stress
CA CB CC
from up to min in μ max in μ max in N min in μ max in μ min in N max in N min in μ max in μ min in N max in N
10
18
30
50
80
120
180
250
18
30
50
80
120
180
250
315
+4
+4
+4
+6
+6
+6
+8
+8
-4
-4
-4
-6
-6
-6
-8
-8
80
120
160
380
410
540
940
1080
-2
-2
-2
-3
-3
-3
-4
-4
-10
-10
-10
-15
-15
-15
-20
-20
30
40
60
140
150
200
330
380
330
480
630
1500
1600
2150
3700
4250
-8
-8
-8
-12
-12
-12
-16
-16
-16
-16
-16
-24
-24
-24
-32
-32
230
340
450
1080
1150
1500
2650
3000
660
970
1280
3050
3250
4300
7500
8600

Standard clearance of paired bearings one row metric taperd roller bearings

Bore in mm Axial clearance
Serie 320X Serie 302, 322 Serie 313(X)
from up to min in μ max in μ min in μ max in μ min in μ max in μ

30
40
50
65
80
100
120
140
160
180
200
225
250
30
40
50
65
80
100
120
140
160
180
200
225
250
280
80
100
120
140
160
190
220
240
270
310
340
390
440
490
120
140
160
180
200
230
280
300
330
370
400
450
500
550
100
120
140
160
180
210
220
240
270
310
340
390
440
490
140
160
180
200
220
270
280
300
330
370
400
450
500
550
60
70
80
100
110
110
130
160
180




100
110
120
140
170
170
190
220
240




Axial clearance of cylindrical roller bearings

Bore Axial serial clearance of bearing
d in mm NUP 2 NJ 2 + HJ NUP 3 NJ 3 + HJ NUP 4 NJ 4 + HJ NUP 22 NJ 22 + HJ NUP 23 NJ 23 + HJ
min in μ max in μ min in μ max in μ min in μ max in μ min in μ max in μ min in μ max in μ min in μ max in μ min in μ max in μ min in μ max in μ min in μ max in μ min in μ max in μ
15
17
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
120
130
140
150
160
170
180
190
200
220
240
260
280

37
37
37
37
47
47
47
47
47
47
47
47
47
47
62
62
62
62
62
62
62
62
62
62
87
87
87
87
87
95



140
140
140
140
155
155
155
155
155
155
155
155
155
155
180
180
180
180
180
180
180
180
180
180
230
230
230
230
230
230


42
42
42
42
42
52
52
52
52
52
52
52
52
52
52
72
72
72
72
72
72
72
72
72
72
102
102
102
102
102
110
110
110
110
165
165
165
165
165
185
185
185
185
185
185
185
185
185
185
215
215
215
215
215
215
215
215
215
215
275
275
275
275
275
290
310
310
310

37
37
47
47
47
47
47
47
47
62
62
62
62
62
62
62
62
87
87
87
87
87
87
87









140
140
155
155
155
155
155
155
155
180
180
180
180
180
180
180
180
230
230
230
230
230
230
230








42
42
42
52
52
52
52
52
52
52
72
72
72
72
72
72
72
72
102
102
102
102
102
102
102
110







165
165
165
185
185
185
185
185
185
185
215
215
215
215
215
215
215
215
275
275
275
275
275
275
275
310












55
55
55
70
70
70
70
70
70
























155
155
155
185
185
185
185
185
185























60
60
60
60
80
80
80
80
80
80
80
110
110
110
110
110
110
110















200
200
200
200
235
235
235
235
235
235
235
290
290
290
290
290
290
310












37
47
47
47
47
47
47
47
47
62
62
62
62
62
62
62
62
87
87
87
87
87
87
87









140
155
155
155
155
155
155
155
155
180
180
180
180
180
180
180
180
230
230
230
230
230
230
230









42
52
52
52
52
52
52
52
52
72
72
72
72
72
72
72
72
102
102
102
102
102
102
102
140
140
140






165
185
185
185
185
185
185
185
185
215
215
215
215
215
215
215
215
275
275
275
275
275
275
275
375
375
375






47
47
47
47
62
62
62
62
62
87
87
87
87
87
87
87
87
120
120
120
120
120
120
120









155
155
155
155
180
180
180
180
180
230
230
230
230
230
230
230
230
315
315
315
315
315
315
315









52
52
52
52
72
72
72
72
72
102
102
102
102
102
102
102
102
140
140
140
140
140
140
140
140








183
183
183
183
215
215
215
215
215
275
275
275
275
275
275
275
275
375
375
375
375
375
375
375
375





Journal-bearing bushes:

As previously reported, one is in certain cases forced to mount journal-bearing bushes. The following table lists the properties of the most common journal-bearing materials. Sliding speed: v = n.p.d. Image450 in m/s (d in mm – n in 1/min) Surface pressure: p = Image451 in N/mm2 (F in N – d in mm – b in mm)

++ : excellent +: good 0: applicable -: not suitable Bronze Powder bronze Bronze with axial split PTFE- Composite POM- Composite Composite with RVS-back PTFE polymide Wound bush
Self-lubricating properties + ++ + ++ ++ ++
Maintenance free operation + 0 ++ + ++ ++ ++
Contaminating circumstances + 0 ++ 0 +
Corrosion resistance + 0 + 0 0 ++ ++ ++
High temperature + + ++ 0 + 0 +
High load 0 0 + ++ + 0 ++
Colliding loads/vibrations + 0 + 0 0 0 ++
High sliding speeds ++ 0 + + + 0
Low friction + ++ ++ ++ 0 ++
Less well surface quality axis + 0 0 0 0
Small working clearance 0 0 ++ + + 0
Less sensitive for tilt + 0 0 0 0 +
Low price level 0 + + ++ ++ ++
Temperature range in °C -40…+150 -10….+100 -40….+150 200….+250 -40….+110 -150….+150 -30….+110 -50….+140
Coefficient of friction μ 0,08…0,1550 0,05..0,1010 0,08..0,1540 0,03..0,0880 0,04..0,12120 0,03..0,0880 0,06..0,1540 0,03..0,08140
Admissible surface pressure in N/mm22 –dynamic -static 140 50 120 250 250 300 80 200
Admissible sliding speed in m/s 0,5 0,25….10 1,0 2,0 2,0 1,5 1,0 0,5
Shaft tolerance e7….e8 f7….f8 e7….f8 f6….h7 h7….h8 g6….f7 h8….h9 h7….h8
Housing tolerance H7 H7 H7 H7 H7 H7 H7 H7
Surface hardness of shaft, Ra. in μm 0,8…1,6 0,2….0,8 0,4….0,8 0….0,4 0….0,8 0….0,4 0….0,8 0….0,8
Surface hardness of shaft. in HB 180….400 200….300 150….400 300….600 150….600 300….600 100….300 200….600