Deep groove ball bearings

- Apr 29, 2019-

Deep groove ball bearings are available in single row and double row designs.




Single row bearings are particularly suitable where:




  • high and very high speeds are required

  • the bearing arrangement must be operated with very low friction

  • very low running noise is required, without reducing the speed, load carrying capacity and operating life of the bearing (Generation C) ➤ link

  • high demands are made on the sealing of the bearing, without increasing heat generation or limiting the speed (Generation C) ➤ section

  • the bearing position is to be designed particularly economically.




Double row bearings can be considered for bearing arrangements where:




  • the load carrying capacity of single row deep groove ball bearings is no longer sufficient ➤ link

  • axial loads in both directions and/or tilting moments must be supported in addition to radial loads ➤ link

  • a high load carrying capacity is required and the design envelope available in a radial and axial direction is relatively small.






Figure 1
Comparison of standard deep groove ball bearings with bearings of Generation C: running noise, frictional torque

C =  bearings of Generation C
MR =  frictional torque
nG =  limiting speed


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Bearing design




Single row deep groove ball bearings are available as:







Double row deep groove ball bearings are available as:





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Single row deep groove ball bearings are also available in many other designs and sizes, as well as for specific applications, by agreement. Corrosion-resistant bearings ➤ TPI 64, larger catalogue bearings ➤ GL 1.



Standard bearings

✎Proven and versatile bearings with high market shares

Single row deep groove ball bearings are self-retaining units, which are part of the group of radial ball bearings. The solid outer and inner rings have deep raceway grooves, with shoulders which are not generally interrupted by filling slots ➤ Figure 2. Solid cages made from polyamide PA66 or brass, and sheet metal cages made from steel or brass, are used as standard cages ➤ Table 4. The bearings are open or sealed. Due to the manufacturing processes used, open bearings, which are also available as sealed versions, can have turned recesses in the outer and inner ring for sealing washers or sealing shields.




Single row deep groove ball bearings are particularly versatile, robust in operation, easy to maintain and very economical. Due to their significant advantages, they are the most widely used rolling bearings worldwide. As a result, Schaeffler also manufactures these bearings in a large number of sizes and designs.








Figure 2
Single row deep groove ball bearings, open or sealed

Fr =  radial load
Fa =  axial load
Symbole/00016410_mei_in_0k_0k.gif  Open
Symbole/00016411_mei_in_0k_0k.gif  Sealing shield on both sides (non-contact)
Symbole/00016412_mei_in_0k_0k.gif  Contact seal on both sides


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Deep groove ball bearings of Generation C



Deep groove ball bearings of Generation C correspond in their structure to single row standard deep groove ball bearings, but are specially optimised in relation to:




  • significantly quieter running

  • even more effective sealing

  • a further reduction in the already very low frictional torque.




Schaeffler has analysed the causes of noise generation in deep groove ball bearings using the most advanced methods. On the basis of the findings obtained from these analyses:




  • The surface of the raceways has been improved

  • The ball quality has been increased

  • Osculation has been optimised

  • The production tolerances have been reduced

  • Deep groove ball bearings have been fitted with new riveted cages made from steel.


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The result of this is a noise reduction in Generation C bearings over comparable standard deep groove ball bearings.
✎Gen. C = particularly high sealing effect due to new and improved seals

The quality of the seal not only has a considerable influence on the rating life, but also on the efficiency of a rolling bearing. As a result, the seal must not only protect the running system reliably against contamination, the ingress of moisture and the loss of grease, but also ensure that the total frictional torque and heat generation in the bearing remain low despite the high sealingaction. The new sealing shields, non-contact seals and contact seals of Generation C deep groove ball bearings (suffixes Z, BRS, HRS, ELS) demonstrate the success of Schaeffler in performing this difficult technical step effectively ➤ Figure 3 and ➤ Figure 4. Description of sealing shields and seals ➤ section .




Electric motors, electrical machinery, washing machines, ventilators and electric tools are the preferred application areas of single row deep groove ball bearings. However, in order to facilitate further increases in the efficiency of these motors, machines and tools, the power loss occurring in the bearing arrangements must be reduced. The above-mentioned measures for reducing noise also resulted, for example, in an approximate reduction in friction of 35%, giving the designer a range of application-specific advantages:




  • lower heat generation

  • a longer grease operating life

  • higher possible speeds

  • a longer bearing operating life

  • a reduced energy consumption

  • lower energy costs

  • lower overall cost of the bearing position.


✎Gen. C = a leading player among single row deep groove ball bearings

In summary, this means that, in addition to their technical advantages, bearing positions with deep groove ball bearings of Generation C are also considerably more economical than bearing arrangements with single row standard deep groove ball bearings. Generation C is available in series 60, 62 and 63.








Figure 3
Single row deep groove ball bearings, Generation C, open or with non-contact seals

Symbole/00016410_mei_in_0k_0k.gif  Open
Symbole/00016411_mei_in_0k_0k.gif  Sealing shield on both sides (suffix 2Z)
Symbole/00016412_mei_in_0k_0k.gif  Non-contact seal on both sides (suffix 2BRS)


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Figure 4
Single row deep groove ball bearings, Generation C, contact seals

Symbole/00016410_mei_in_0k_0k.gif  Contact seal on both sides (suffix 2HRS)
Symbole/00016411_mei_in_0k_0k.gif  Contact seal on both sides (suffix 2ELS)


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Matched bearing sets

✎Bearing sets in O, X or tandem arrangements

If the load carrying capacity of a single bearing is not sufficient, or the shaft is to be guided axially in both directions with a defined clearance, single row standard deep groove ball bearings are also available as matched bearing sets ➤ Figure 5.


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As the arrangement of the bearing pairs is specific to the application, Schaeffler supplies bearing sets by agreement.






Figure 5
Matched bearing sets

Fr = radial load
Fa =  axial load
Symbole/00016410_mei_in_0k_0k.gif  Set in O arrangement
Symbole/00016411_mei_in_0k_0k.gif  Set in X arrangement
Symbole/00016412_mei_in_0k_0k.gif  Set in tandem arrangement


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Corrosion-resistant bearings

✎Wide product range

Corrosion-resistant bearings are suitable where particular requirements for corrosion protection are present. Schaeffler supplies deep groove ball bearings of this type in open and sealed designs.


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The load carrying capacity for bearings made from corrosion-resistant steel is slightly lower than for bearings made from rolling bearing steel.
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The range of these bearings and housings is described in detail in Technical Product Information TPI 64 ➤ TPI 64.



Double row deep groove ball bearings

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Double row deep groove ball bearings of series 42 and 43correspond in their structure and function to single row deep groove ball bearings arranged in pairs ➤ Figure 6. They have deep raceway grooves in the bearing rings and a narrow osculation between the raceway grooves and balls. However, they are slightly narrower than two single row deep groove ball bearings of the series 62 and 63 with the same bore and outside diameter.




Figure 6
Double row deep groove ball bearing, open

Fr =  radial load
Fa =  axial load


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Load carrying capacity




Single row deep groove ball bearings – radial load carrying capacity

✎Suitable for predominantly radial loads

The balls are in contact with the raceways at one point only. Under purely radial load, the contact points between the rolling elements and raceways lie at the centre of the raceway. As a result, the connection between the contact points passes through the radial plane, i.e. the optimum load direction is a purely radial load ➤ Figure 2.


✎Larger bearing cross-sections permit higher loads

The load carrying capacity is dependent on the bearing series. As a result, deep groove ball bearings of series 618 and 619, with their smaller bearing cross-sections, cannot support loads as high as series 60, 62 and 63 – with identical dimensions relative to bore diameter d – with their larger cross-sections ➤ Figure 7.








Figure 7
Single row deep groove ball bearings, comparison of cross-section and load carrying capacity (radial load carrying capacity Cr) for bearings with d = 40 mm

Cr =  basic dynamic load rating


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Single row deep groove ball bearings – axial load carrying capacity

✎Capable of supporting axial loads in both directions

Due to the deep raceway grooves in the bearing rings and the narrow osculation between the raceway grooves and balls, single row deep groove ball bearings can support axial loads in both directions ➤ Figure 2. The axial load carrying capacity is dependent, for example, on the bearing size, the internal construction and the operating clearance. If the axial load is too high, however, this can increase the running noise and considerably reduce the operating life of the bearings.


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If there is any uncertainty regarding the axial load carrying capacity of the bearings, please consult Schaeffler.



Double row deep groove ball bearings

✎Considerably higher loadcarrying capacity than single row bearings

Due to the larger number of rolling elements, double row deep groove ball bearings can be subjected to greater loads than single row deep groove ball bearings with an identical ball set. They can replace two single row deep groove ball bearings if a smaller design envelope width is required.


✎Also suitable for tiltingmoment loads

Double row deep groove ball bearings can also support tiltingmoment loads in addition to radial and axial loads ➤ Figure 8. They are therefore suitable for particularly short shafts that are supported by only one bearing.


Figure 8
Unilateral bearing arrangement of a shaft with a double row deep groove ball bearing (flying bearing arrangement)

Fr =  radial load
Fa =  axial load
M =  tilting moment load


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