Self-aligning Ball Bearing

The raceway surface of the outer ring of the self-aligning ball bearing is a spherical surface, and its center of curvature is consistent with the center of the bearing. Therefore, the inner ring, outer ring, ball, and cage can be tilted to a certain extent, and they can rotate freely around the center of the bearing, and have automatic centering performance, which can automatically adjust the axis center deviation of the shaft and the box due to improper processing and installation. It is suitable for occasions where it is difficult to align the shaft and the box, and the shaft is prone to deflection.

Self-aligning ball bearings are mainly used to bear radial loads. While bearing radial loads, they can also bear a small amount of axial loads. They are not suitable for bearing pure axial loads. Due to the self-aligning ability of this bearing, it is suitable for occasions with low speed and centering requirements. If the bearing capacity of the self-aligning ball bearing is not enough, the self-aligning roller bearing with the same self-aligning performance should be used.

Self-aligning ball bearing application range: woodworking machinery, textile machinery transmission shaft.

The inner diameter of the self-aligning ball bearing has a cylindrical bore or a tapered bore. The taper of the conical inner hole is 1:12 (the rear code is K). C&U can provide self-aligning ball bearings with cylindrical bore or tapered bore on the inner diameter surface.

C&U can provide self-aligning ball bearings with seals. Both sides of the self-aligning ball bearings have contact sealing rings, and the sealing lips contact the smooth bevels of the inner ring with light pressure. If necessary, please consult the technology center of C&U Group.

Self-aligning ball bearings with extended inner ring and special bore tolerances simplify mounting and dismounting. If necessary, please consult the technology center of C&U Group.

 

1. Structural form

1. Ordinary type (Fig. 1): self-aligning ball bearing with cylindrical inner diameter surface;
2. Conical hole type (Fig. 2): self-aligning ball bearing with a taper on the inner diameter surface, the taper is 1:12;
3. Sealed type (Figure 3): Self-aligning ball bearings with sealing rings on both sides;
4. Wide inner ring type (Fig. 4): self-aligning ball bearing with extended inner ring.

 

2. Dimensional accuracy and rotation accuracy

Tolerances for radial bearings (except tapered roller bearings)

 

3. Radial clearance

C&U standard self-aligning ball bearings with cylindrical bore adopt common group clearance, and self-aligning ball bearings with conical inner holes use C3 group clearance as the standard type. Self-aligning ball bearings with a clearance larger or smaller than the standard group can be provided according to user requirements. The clearance of self-aligning ball bearings with extended inner ring is between group C2 and ordinary group.

See Table 6.11 for radial clearance values of self-aligning ball bearings with cylindrical bores, and Table 6.12 for radial clearance values of self-aligning ball bearings with tapered bores. These data are the clearance values when the bearing is not loaded before installation.

Table 6.11 Radial clearance of self-aligning ball bearings (cylindrical bore)

Bearing Nominal Inner Diameter d(mm)		Clearance(μm)
		2 set		0 set		3 set		4 set		5 set
Exceed	Arrive	The smallest	Maximum	The smallest	Maximum	The smallest	Maximum	The smallest	Maximum	The smallest	Maximum
2.5 6 10 14 18 24 30 40 50 65 80 100 120 140	6 10 14 18 24 30 40 50 65 80 100 120 140 160	1 2 2 3 4 5 6 6 7 8 9 10 10 15	8 9 10 12 14 16 18 19 21 24 27 31 38 44	5 6 6 8 10 11 13 14 16 18 22 25 30 35	15 17 19 21 23 24 29 31 36 40 48 56 68 80	10 12 13 15 17 19 23 25 30 35 42 50 60 70	20 25 26 28 30 35 40 44 50 60 70 83 100 120	15 19 21 23 25 29 34 37 45 54 64 75 90 110	25 33 35 37 39 46 53 57 69 83 96 114 135 161	21 27 30 32 34 40 46 50 62 76 89 105 125 150	33 42 48 50 52 58 66 71 88 108 124 145 175 210

Table 6.12 Radial clearance of self-aligning ball bearings (tapered bore)

Bearing Nominal Inner Diameter d(mm)		Clearance(μm)
		2 set		0 set		3 set		4 set		5 set
Exceed	Arrive	The smallest	Maximum	The smallest	Maximum	The smallest	Maximum	The smallest	Maximum	The smallest	Maximum
2.5 6 10 14 18 24 30 40 50 65 80 100 120 140	6 10 14 18 24 30 40 50 65 80 100 120 140 160	— — — — 7 9 12 14 18 23 29 35 40 46	— — — — 17 20 24 27 32 39 47 56 68 74	— — — — 13 15 19 22 27 35 42 50 60 65	— — — — 26 18 35 39 47 57 68 81 98 110	— — — — 20 23 29 33 41 50 62 75 90 100	— — — — 33 39 46 52 61 75 90 108 130 150	— — — — 28 33 40 45 56 69 84 100 120 140	— — — — 42 50 59 65 80 98 116 139 165 191	— — — — 37 44 52 58 73 91 109 130 155 180	— — — — 55 62 72 79 99 123 144 170 205 240

 

4. Cage

The cage of the self-aligning ball bearing generally adopts a stamped steel cage, and a glass fiber reinforced nylon cage can also be used. If you need self-aligning ball bearings with nylon cages, please consult the technical center of Renben Group.

 

5. Allowable alignment angle

The internal structure design of the self-aligning ball bearing enables it to have an automatic self-aligning function, that is, the bearing itself can adjust the angular alignment error between the inner and outer rings. Under normal load and working conditions, when the inner ring rotates, the non-concentric angle values given in the table below are allowed. Whether this given value can be fully achieved depends on conditions such as the design of the bearing arrangement and the type of seal.

Bearing series	Allowable non-concentric angle value
1200 series	2.5°
1300 series	3°
2200 series	2.5°
2300 series	3°

 

6. Equivalent dynamic load

Fₐ/Fᵣ<e 时　P=Fᵣ+Y₁Fₐ
Fₐ/Fᵣ>e时　P=0.65Fᵣ+Y₂Fₐ
The corresponding calculation factors e, Y₁, Y₂ for each bearing can be found in the dimension tables.

 

7. Equivalent static load

P₀=Fᵣ+Y₀Fₐ
The Y₀ factor values for each bearing are given in the dimension tables.

 

 

Self-aligning Ball Bearing

FAQ

What our customers said

The raceway surface of the outer ring of the self-aligning ball bearing is a spherical surface, and its center of curvature is consistent with the center of the bearing. Therefore, the inner ring, outer ring, ball, and cage can be tilted to a certain extent, and they can rotate freely around the center of the bearing, and have automatic centering performance, which can automatically adjust the axis center deviation of the shaft and the box due to improper processing and installation. It is suitable for occasions where it is difficult to align the shaft and the box, and the shaft is prone to deflection.