Schaeffler Product catalogue - medias
Ihre Eingaben des Auswahlassistenten werden im Hintergrund gespeichert, Sie können den Assistenten jederzeit wieder aufrufen.
(0)
Single row cylindrical roller bearings with cage
 

Single row cylindrical roller bearings with cage are suitable where:

 
 
  • bearing arrangements are subjected to very high radial loads ➤ section
  • not only high radial forces but also axial loads from one or both directions must be supported by the bearing position (semi-locating or locating bearing function) ➤ section
  • bearing arrangements must have very high rigidity
  • axial displacements of the shaft relative to the housing must be compensated without constraint in the bearing (in the case of bearings with a non-locating or semi-locating bearing
    _dictid_S4260_
    function) ➤ section
  • high radial loads and very high speeds occur but the very high radial load carrying capacity of full complement cylindrical roller bearings is not required ➤ section
  • the bearings should be separable (one bearing ring can be removed) for easier mounting ➤ section .
 
   

Figure 1
Cylindrical roller bearing with cage/full complement bearing, comparison of speed and load carrying capacity

nG =  limiting speed
Cr =  basic dynamic load rating
SL1923 =  full complement cylindrical roller bearing
NJ23 =  cylindrical roller bearing with cage

 

imageref_20352475915_All.gif

 
 

Bearing design

 
 

Single row cylindrical roller bearings with cage are available in the basic design as:

 
   
imageref_18348417035_All.gif   In addition to the bearings described here, Schaeffler supplies single row cylindrical roller bearings with cage in other types, series and dimensions. These products are described in some cases in special publications. If necessary, please contact Schaeffler. Larger catalogue bearings ➤ GL 1.  
 

Bearings of basic design – standard range

Key features

 

Single row cylindrical roller bearings with cage are part of the group of radial roller bearings. In contrast to the ball, the roller has a larger contact area perpendicular to the roller axis. As a result, it can transmit higher forces, has greater rigidity and allows smaller rolling element diameters under the same load. The single row bearings comprise solid outer rings, inner rings and cages that are fitted with a large number of cylindrical rollers. The rollers have profiled ends, i.e. they have a slight lateral curvature towards the ends. This modified line contact between the rolling elements and raceways prevents damaging edge stresses ➤ Figure 2. In all standard designs, the cylindrical rollers are guided between rigid ribs by at least one bearing ring. Together with the cage and rollers, this forms a ready-to-fit unit. The other bearing ring can be removed. As a result, the inner ring and outer ring can be mounted separately. Tight fits can thus be achieved on both rings. Bearings of the basic design are manufactured in many different types that differ essentially in the arrangement of the ribs on the inner ring and outer ring. Depending on the design, they are used as non-locating bearings, semi-locating bearings or locating bearings.

 
   

Figure 2
Roller profile and stress distribution

Symbole/00016410_mei_in_0k_0k.gif  Cylindrical roller profile (high stress peaks)
Symbole/00016411_mei_in_0k_0k.gif  Roller with profiled ends (no stress peak)
Symbole/00016412_mei_in_0k_0k.gif  Cylindrical centre region
Symbole/00016413_mei_in_0k_0k.gif  Region of logarithmic tapering
Symbole/00016414_mei_in_0k_0k.gif  Rounding of edge

 

imageref_9007203706154635_All.gif

 
 

Type NU

Bearings with non-locating bearing
_dictid_N2820_
function

 

In bearings of type NU, the outer ring has two rigid ribs, while the inner ring has no ribs ➤ Figure 3. As a result, axial displacements of the shaft relative to the housing are possible in both directions and within certain limits. During rotational motion, length compensation occurs without constraint in the bearing between the rollers and the raceway without ribs and is therefore practically free from friction. The maximum axial displacement s is given in the product tables. The bearings are used as non-locating bearings, i.e. they cannot guide the shaft axially in either direction ➤ section . For use as semi-locating bearings, they can be combined with the L-section ring HJ ➤ Figure 5.

 
 

Type N

Bearings with non-locating bearing
_dictid_N2820_
function

 

Cylindrical roller bearings of type N have two rigid ribs on the inner ring, while the outer ring has no ribs ➤ Figure 3. Due to the absence of ribs, axial displacements of the shaft relative to the housing are possible in both directions within the bearing. The maximum axial displacement s is given in the product tables. Bearings of type N are used as non-locating bearings, i.e. they cannot guide the shaft axially in either direction ➤ section .

 
   

Figure 3
Single row cylindrical roller bearings – non-locating or semi-locating bearings

Fr = radial load
Fa = axial load
Symbole/00016410_mei_in_0k_0k.gif  Cylindrical roller bearing NU (non-locating bearing)
Symbole/00016411_mei_in_0k_0k.gif  Cylindrical roller bearing N (non-locating bearing)
Symbole/00016412_mei_in_0k_0k.gif  Cylindrical roller bearing NU + L‑section ring HJ (semi-locating bearing)

 

imageref_20347458059_All.gif

 
 

Type NJ

Bearings with semi-locating bearing
_dictid_S4260_
function

 

Bearings of type NJ have two rigid ribs on the outer ring and one rigid rib on the inner ring ➤ Figure 4. With these cylindrical roller bearings, axial displacements of the shaft relative to the housing are possible in one direction only. The maximum axial displacement s is given in the product tables. Bearings of type NJ are used as semi-locating bearings, i.e. they can guide the shaft axially in one direction ➤ section . Semi-locating bearings NJ can be combined with an L-section ring HJ to form a locating bearing unit ➤ Figure 5.

 
 

Type NUP

Bearings with locating bearing function

 

Cylindrical roller bearings of type NUP have two rigid ribs on the outer ring as well as one rigid rib and one loose rib washer on the inner ring ➤ Figure 4. With these cylindrical roller bearings, axial displacements between the shaft and the housing are not possible. Bearings of type NUP are used as locating bearings, i.e. they can guide the shaft axially in both directions ➤ section .

 
   

Figure 4
Single row cylindrical roller bearings – semi-locating or locating bearings

Fr =  radial load
Fa =  axial load
Symbole/00016410_mei_in_0k_0k.gif  Cylindrical roller bearing NJ (semi-locating bearing)
Symbole/00016411_mei_in_0k_0k.gif  Cylindrical roller bearing NUP (locating bearing)

 

imageref_20347460235_All.gif

 
 

L-section rings

Functional expansion by means of L-section rings

 

In order to expand the function of cylindrical roller bearings NU and NJ, these types can be combined with L-section rings HJ ➤ Figure 5. In this way, bearings NU can perform a semi-locating bearing
_dictid_S4260_
function, while bearings NJ in combination with L-section rings can perform a locating bearing function ➤ Figure 5.

 
imageref_17757187211_All.gif   Cylindrical roller bearings NU must not be mounted with two L-section rings, since this can lead to axial bracing of the rollers.  
 

L-section rings can be advantageous where:

 
 
  • the inner ring in locating bearing arrangements that are subjected to high loads has a very tight fit; bearings of type NJ + HJ permit tighter fits than bearings NUP, which have a shortened inner ring and a loose rib washer
  • the shaft must be axially guided in one or both directions and bearings NJ or NUP are not available
  • the design of the bearing arrangement and the mounting and dismounting of the bearings should be simplified.
 

Design of L-section rings

 

The L-section rings are made from rolling bearing steel and are hardened and ground. The axial runout of the lateral faces corresponds to the normal tolerances of the appropriate bearings. Where available, the L-section rings are listed in the product tables together with the associated bearings (e.g. bearing NJ206-E-TVP2 + L-section ring HJ206-E). Since the L-section rings are not a component of the bearing, these must always be ordered together with the bearing ➤ Figure 14.

 
   

Figure 5
Cylindrical roller bearings with L-section rings – semi-locating or locating bearings

Fr =  radial load
Fa =  axial load
Symbole/00016410_mei_in_0k_0k.gif  Cylindrical roller bearing NU + L‑section ring HJ (semi-locating bearing)
Symbole/00016411_mei_in_0k_0k.gif  Cylindrical roller bearing NJ + L‑section ring HJ (locating bearing)

 

imageref_20347462411_All.gif

 
 

X-life premium quality

imageref_19964530187_All.gif   Single row cylindrical roller bearings with cage are supplied up to an outside diameter D = 320 mm as X-life bearings ➤ Figure 6. These bearings exhibit considerably higher performance than comparable standard cylindrical roller bearings. This is achieved, for example, through the modified internal construction, the optimised contact geometry between the rollers and raceways, the better surface quality ➤ Figure 7 and the optimised roller guidance and lubricant film formation.  
   

Figure 6
Cylindrical roller bearing in X-life design

Symbole/00016410_mei_in_0k_0k.gif  Brass cage
Symbole/00016411_mei_in_0k_0k.gif  Cylindrical roller, honed
Symbole/00016412_mei_in_0k_0k.gif  Outer ring, honed
Symbole/00016413_mei_in_0k_0k.gif  Inner ring, honed

 

imageref_20347464587_All.gif

 
   

Figure 7
Comparison of surface qualities

Symbole/00016410_mei_in_0k_0k.gif  Standard surface – a rough surface causes stress peaks under radial load
Symbole/00016411_mei_in_0k_0k.gif  X-life surface – a higher surface quality reduces stress peaks; this increases the bearing operating life

 

imageref_20347466763_All.gif

 
 

Advantages

 

These technical enhancements offer a range of advantages, such as:

 
 
  • a more favourable load distribution in the bearing and thus a higher dynamic load carrying capacity of the bearings ➤ Figure 2 and ➤ Figure 8
  • a higher fatigue limit load
  • lower heat generation in the bearing
  • lower lubricant consumption and therefore longer maintenance intervals if relubrication is carried out
  • a measurably longer operating life of the bearings
  • high operational security
  • compact, environmentally-friendly bearing arrangements.
 

Interchangeable with comparable standard bearings

 

Since X-life cylindrical roller bearings have the same dimensions as the corresponding standard bearings, the latter can be replaced without any problems by the higher-performance X-life bearings. The major advantages of X-life can therefore also be used for existing bearing arrangements with standard bearings.

 

Lower operating costs, higher machine availability

 

In conclusion, these advantages improve the overall cost-efficiency of the bearing position significantly and thus bring about a sustainable increase in the efficiency of the machine and equipment.

 

Suffix XL

 

X-life cylindrical roller bearings include the suffix XL in the designation ➤ section and ➤ dimension table.

 
   

Figure 8
Cylindrical roller bearing with cage: comparison of basic dynamic load rating Cr with bearings without X-life quality

Cr =  radial basic dynamic load rating
Symbole/00016410_mei_in_0k_0k.gif  Bearing without X-life quality
Symbole/00016411_mei_in_0k_0k.gif  X-life cylindrical roller bearing

 

imageref_20352488203_All.gif

 
 

Areas of application

Areas of application

 

Due to their special technical features, X-life cylindrical roller bearings are highly suitable, for example, for bearing arrangements in:

 
 
  • heavy industry (steel production)
  • power transmission (gearbox engineering)
  • processing machines and construction machinery
  • wind turbines (gearbox applications).
 
imageref_17757210635_All.gif   X-life indicates a high product performance density and thus a particularly significant benefit to the customer.  
 

Load carrying capacity

 
 

Depending on the type, single row cylindrical roller bearings can support not only very high radial forces but also high axial loads on one or both sides:

 
 
  • The types N and NU can only support radial loads. If NU bearings  are combined with an L-section ring, these can also support axial loads on one side ➤ Figure 3.
  • The type NJ can support axial loads on one side and radial loads. If this type is combined with an L-section ring, it can support axial loads on both sides ➤ Figure 5.
  • The type NUP can support axial loads on both sides and radial loads.
 

Higher capacity roller set in variant E

 

Bearings with the suffix E have a higher capacity roller set and are thus designed for very high load carrying capacity.

 
 

Higher axial load carrying capacity of bearings with toroidal crowned roller end face

Neither wear nor fatigue occurs on the rib contact running and roller end faces

 

In the case of cylindrical roller bearings with toroidal crowned rollers (TB design), the axial load carrying capacity has been significantly improved with the aid of new calculation and manufacturing methods. A special curvature of the roller end faces facilitates optimum contact conditions between the rollers and ribs ➤ Figure 9. As a result, the axial contact pressures on the rib are significantly minimised and a lubricant film capable of supporting higher loads is formed. Under standard operating conditions, this completely eliminates wear and fatigue at the rib contact running and roller end faces. In addition, the frictional torque is reduced by up to 50%. The bearing temperature during operation is therefore significantly lower. Bearings of the toroidal crowned design are available for a bore diameter of, or larger than, d = 170 mm ➤ dimension table.

 
   

Figure 9
Contact geometry of roller end face/rib face – modified roller end faces

Symbole/00016410_mei_in_0k_0k.gif  Cylindrical roller with inner ring
Symbole/00016411_mei_in_0k_0k.gif  Detail (representation not to scale)
Symbole/00016412_mei_in_0k_0k.gif  End of roller
Symbole/00016413_mei_in_0k_0k.gif  Rib

 

imageref_22351627915_All.gif

 
 

Load ratio Fa/Fr

Ratio Fa/Fr ≦ 0,4 or 0,6

 

The bearings can support axial loads on one side by means of the ribs on the inner and/or outer ring ➤ Figure 10. In order to ensure problem-free running (tilting of the rollers is prevented), they must always be subjected to radial load at the same time as axial load. The ratio Fa/Fr must not exceed the value 0,4. For bearings with toroidal roller ends (TB design), values up to 0,6 are permissible.

 
imageref_17757187211_All.gif   Continuous axial loading without simultaneous radial loading is not permissible.  
 

Permissible axial load

 

Axial loads are supported by the bearing ribs and the roller end faces ➤ Figure 4. The axial load carrying capacity of the bearing is therefore essentially dependent on:

 
 
  • the size of the sliding surfaces between the ribs and the end faces of the rolling elements
  • the sliding velocity at the ribs
  • the lubrication of the contact surfaces
  • tilting of the bearing
  • friction.
 
   

Figure 10
Force flow under axial load – semi‑locating bearing NJ


 

imageref_20352498059_All.gif

 
 

Calculation of permissible axial load – cylindrical rollers with conventional roller ends

Bearings with standard roller ends

 

The permissible axial load Fa per can be calculated from the hydrodynamic load carrying capacity of the contact ➤ Equation 1.

 

Equation 1
Permissible axial load – bearings of standard design
 
imageref_20895919499_All.gif

Legend

 
Fa per
 N
Permissible continuous axial load. In order to prevent unacceptably high temperatures in the bearing, Fa per must not be exceeded
Fa max
 N
Maximum continuous axial load in relation to rib fracture. In order to prevent unacceptably high pressures at the contact surfaces, Fa max must not be exceeded
kS
Factor as a function of lubrication method ➤ Table 1. The factor takes into consideration the lubrication method used for the bearing. The better the lubrication and, in particular, the heat dissipation, the higher the permissible axial load
kB
Factor as a function of bearing series ➤ Table 2
dM
 mm
Mean bearing diameter dM = (D + d)/2 ➤ dimension table
n
 min–1
Operating speed.
 
   
Table 1
Factor kS
 

Lubrication method
Factor
kS
from
to
Minimal heat dissipation, drip feed oil lubrication,
oil mist lubrication, low operating viscosity (ν < 0,5 · ν1)
7,5
10
Poor heat dissipation, oil sump lubrication,
oil spray lubrication, low oil flow
10
15
Good heat dissipation, recirculating oil lubrication
(pressurised oil lubrication)
12
18
Very good heat dissipation, recirculating oil lubrication
with oil cooling, high operating viscosity (ν > 2 · ν1)
16
24

 
imageref_17757187211_All.gif   The precondition for these kS values is an operating viscosity of the lubricant of at least the reference viscosity ν1 in accordance with DIN ISO 281:2010.  
imageref_17757201419_All.gif   Doped lubricating oils should be used, such as CLP (DIN 51517) and HLP (DIN 51524) of ISO VG grades 32 to 460, as well as ATF oils (DIN 51502) and transmission oils (DIN 51512) of SAE viscosity grades 75W to 140W.  
 

   
Table 2
Bearing factor kB
 

Series
Factor
kB
NJ2..-E, NJ22..-E, NUP2..-E, NUP22..-E
15
NJ3..-E, NJ23..-E, NUP3..-E, NUP23..-E
20
NJ4
22

 
 

Calculation of permissible axial load – cylindrical rollers with toroidal roller ends

Higher axial loads possible

 

For bearings with toroidal roller ends, the permissible axial loads are 50% higher ➤ Equation 2.

 

Equation 2
Permissible axial load – bearings of TB design
 
imageref_20897364363_All.gif

 

Calculation of maximum permissible axial load

imageref_17757187211_All.gif   For bearings with rollers of the standard or TB design, the maximum permissible axial load Fa max ➤ Equation 3 is calculated from the rib strength and the security against wear. This must not be exceeded, even if Fa per gives higher values ➤ Equation 4.  
 


Equation 3
Maximum axial load – bearings of standard and TB design
 
imageref_9007203347529355_All.gif


Equation 4
Permissible axial load
 
imageref_18014402602262667_All.gif

 

Axial load under shaft deflection

Permissible axial load under shaft deflection of up to 2′

 

Under considerable shaft deflection, the shaft shoulder presses against the inner ring rib. In combination with the active axial load, this can lead to high alternating loading of the inner ring ribs. Under a shaft deflection of up to 2′, the permissible axial load can be estimated ➤ Equation 5.

 
imageref_18348417035_All.gif   If more severe tilting is present, a separate strength analysis is required. In this case, please contact Schaeffler.  
 


Equation 5
Axial load under misalignment
 
imageref_952717451_All.gif

Legend

 
Fas
 N
Permissible axial load under misalignment.
 
 

Compensation of angular misalignments

 

Angular deviations are misalignments between the inner and outer ring

 

The possible misalignment between the inner ring and outer ring is influenced by the internal bearing construction, the operating clearance, the forces acting on the bearing etc. Due to these complex relationships, it is not possible to give generally valid absolute values here. However, misalignments (angular deviations) between the inner ring and outer ring will generally always have an effect on the running noise and the operating life of the bearings.

 
 

The permissible guide values at which, based on experience, there is no significant reduction in operating life are as follows:

 
 
  • 4′ for series 10, 19, 2, 3, 4
  • 3′ for series 22, 23.
 
 

The values apply to:

 
 
  • bearing arrangements with static misalignment (consistent position of the shaft and housing axis)
  • bearings that are not required to perform an axial guidance function
  • bearings subjected to small loads (with C0r/P ≧ 5).
 
imageref_18348417035_All.gif   Checking by means of the calculation program BEARINX is recommended in all cases. If there is any uncertainty regarding possible misalignment, please consult Schaeffler.  
 

Lubrication

 

Oil or grease lubrication

 

Single row cylindrical roller bearings with cage are not greased. They must be lubricated with oil or grease.

 

Compatibility with plastic cages

 

When using bearings with plastic cages, compatibility between the lubricant and the cage material must be ensured if synthetic oils, lubricating greases with a synthetic oil base or lubricants containing a high proportion of EP additives are used.

 
imageref_18348417035_All.gif   If there is any uncertainty regarding the suitability of the selected lubricant for the application, please consult Schaeffler or the lubricant manufacturer.  

Observe oil change intervals

 

Aged oil and additives in the oil can impair the operating life of plastics at high temperatures. As a result, stipulated oil change intervals must be strictly observed.

 
 

Sealing

 
 

The bearings are not sealed; i.e. sealing of the bearing position must be carried out in the adjacent construction. This must reliably prevent:

 
 
  • moisture and contaminants from entering the bearing
  • the egress of lubricant from the bearing.
 
 

Speeds

 
 

The product tables give two speeds for most bearings ➤ dimension table:

 
 
  • the kinematic limiting speed nG
  • the thermal speed rating nϑr.
 
 

Limiting speeds

imageref_17757187211_All.gif   The limiting speed nG is the kinematically permissible speed of the bearing. Even under favourable mounting and operating conditions, this value should not be exceeded without prior consultation with Schaeffler    ➤ link.  
 

Reference speeds

nϑr is used to calculate nϑ

 

The thermal speed rating nϑr is not an application-oriented speed limit, but is a calculated ancillary value for determining the thermally safe operating speed nϑ    ➤ link.

 
 

Noise

 
 

The Schaeffler Noise Index (SGI) has been developed as a new feature for comparing the noise level of different bearing types and series. As a result, a noise evaluation of rolling bearings can now be carried out for the first time.

 
 

Schaeffler Noise Index

 

The SGI value is based on the maximum permissible noise level of a bearing in accordance with internal standards, which is calculated on the basis of ISO 15242. In order that different bearing types and series can be compared, the SGI value is plotted against the basic static load rating C0.

 
 

This permits direct comparisons between bearings with the same load carrying capacity. The upper limit value is given in each of the diagrams. This means that the average noise level of the bearings is lower than illustrated in the diagram.

 
imageref_17757187211_All.gif   The Schaeffler Noise Index is an additional performance characteristic in the selection of bearings for noise-sensitive applications. The specific suitability of a bearing for an application in terms of installation space, load carrying capacity or speed limit for example, must be checked independently of this.  
 

   

Figure 11
Schaeffler Noise Index for single row cylindrical roller bearings with cage

SGI =  Schaeffler Noise Index
C0 =  basic static load rating

 

imageref_23602466699_All.gif

 
 

Temperature range

 
 

The operating temperature
_dictid_O940_
of the bearings is limited by:

 
 
  • the dimensional stability of the bearing rings and cylindrical rollers
  • the cage
  • the lubricant.
 
 

 

Possible operating temperatures of single row cylindrical roller bearings ➤ Table 3.

 
   
Table 3
Permissible temperature ranges
 

Operating temperature
Single row cylindrical roller bearings
with polyamide cage PA66
with brass or sheet steel cage
imageref_19988082955_All.gif
   
–30 °C to +120 °C
–30 °C to +150 °C
For continuous operating temperatures higher than +120 °C, please contact us

 
imageref_18348417035_All.gif   In the event of anticipated temperatures which lie outside the stated values, please contact Schaeffler.  
 

Cages

 
 

The right cage for any purpose

Standard materials are plastic, brass and steel

 

Approximately two-thirds of Schaeffler cylindrical roller bearings are supplied with cages. For standard applications, the cage materials used essentially are plastic, brass and sheet steel. A large number of cage types and sizes are designed using these three materials. As a result, the right bearing – in accordance with the operating conditions – is always available. For cylindrical roller bearings standardised in accordance with DIN 5412, there are four standard cages available for selection. A summary of the various cage characteristics and their suitability for certain applications is shown in ➤ Table 4.

 

Plastic cage TVP2

 

The highly versatile plastic cage TVP2 is the standard cage for bearings up to a medium bearing diameter ➤ Table 5. In comparison with metal cages, it has a range of advantages: low mass, low running noises due to good damping, high elasticity, good tribological characteristics with steel rolling elements and very good emergency running characteristics. This cage is thus a good choice for applications that allow the use of a plastic cage. Due to their wide-ranging positive characteristics, such plastic cages are now in use in many millions of bearings and applications.

 

Two-piece solid brass cage M1

 

A classic design of brass cage is the two-piece, riveted-bar brass cage M1 ➤ Table 5. It comprises a so-called comb cage and a cage cover. The cage parts are joined by means of hot riveting, where the rivet pin is integrated in the cage comb.

 

One-piece, milled brass cage MPAX/MPBX

 

The brass cage MPAX or MPBX is intended for demanding conditions, such as the high speeds and radial accelerations occurring in planetary gear bearing arrangements ➤ Table 4. The optimised pocket geometry and the minimised mass allow a lower running temperature than comparable brass cages. The cages differ in the type of rib guidance. Cage MPAX is guided on the outer ring rib and cage MPBX is guided on the inner ring rib.

 

Sheet steel cage JP3

 

For applications that require increased temperature resistance, good lubrication and high geometrical stability of the cage, a bearing with a sheet steel cage is often the most economical solution ➤ Table 4. With the aid of highly developed manufacturing technologies, the geometry of the crosspieces and thus the running contact of the rollers on the cage bars is significantly improved. This goes hand in hand with a favourable surface structure, which has a positive influence on lubricant film formation.

 
 

   
Table 4
Cage, cage characteristics, suitability
 

Criteria
Cage
TVP2
M1
JP3
MPAX
MPBX

 

 

 

 

 
Large number
of rolling elements
+
+
+
+
+
High radial cage rigidity

+++
+
+++
+++
Low mass
+++

+


Good emergency running (damage case)

+++
+
+++
+++
Low noise
+++
+
+
+
+
High guidance
normal acceleration
+
+
+
+++
+++
Strong vibrations
+
+
+
+++
+++
Relubrication facility


+++
+
+
Grease/oil compatibility

+
+++
+
+
Application temperatures > 120 °C

+
+++
+
+
Large temperature fluctuations

+
+++
+
+

 
 
______
+++ =  extremely suitable
+ =  suitable
– =  less suitable
 

Solid cages made from brass and polyamide PA66 are used as standard

 

Standard cages are shown in ➤ Table 5. The cage design is dependent on the bearing series and the bore code. Other cage designs are available by agreement. With such cages, however, suitability for high speeds and temperatures as well as the basic load ratings may differ from the values for the bearings with standard cages.

 
imageref_18348417035_All.gif   For high continuous temperatures and applications with difficult operating conditions, bearings with brass cages should be used. If there is any uncertainty regarding cage suitability, please consult Schaeffler.  
 

   
Table 5
Cage, cage suffix, bore code
 

Bearing series
Solid cage
made from polyamide PA66
Solid brass cage
TVP2
M1
standard
standard
Bore code
NU10
- from 05
NU19
- from 92
NU2..-E, NJ2..-E, NUP2..‑E
up to 26
from 28
NU3..-E, NJ3..-E, NUP3..‑E
up to 28
from 30
NU4, NJ4
- all
NU22..-E, NJ22..-E
up to 26
from 28
NU23..-E, NJ23..-E
up to 22
from 24
N2..-E
up to 20, 22 to 26
21, from 28
N3..-E
up to 16
from 17
NUP22..-E
up to 26
from 28
NUP23..-E
up to 22
from 24

 
 

Internal clearance

 
 

Radial internal clearance

The standard is CN

 

Cylindrical roller bearings with cage are manufactured as standard with the radial internal clearance CN (normal) ➤ Table 6. CN is not stated in the designation.

 
imageref_18348417035_All.gif   Certain sizes are also available by agreement with the larger internal clearance C3, C4 and C5 ➤ Table 6.  
imageref_17757201419_All.gif   The values for radial internal clearance correspond to DIN 620-4:2004 (ISO 5753-1:2009) ➤ Table 6. They are valid for bearings which are free from load and measurement forces (without elastic deformation).  
 

   
Table 6
Radial internal clearance of single row cylindrical roller bearings with cage
 

Nominal
bore diameter
Radial internal clearance
d
CN
(Group N)
C3
(Group 3)
C4
(Group 4)
C5
(Group 5)
mm
μm
μm
μm
μm
over
incl.
min.
max.
min.
max.
min.
max.
min.
max.
- 24
20
45
35
60
50
75
65
90
24
30
20
45
35
60
50
75
70
95
30
40
25
50
45
70
60
85
80
105
40
50
30
60
50
80
70
100
98
125
50
65
40
70
60
90
80
110
110
140
65
80
40
75
65
100
90
125
130
165
80
100
50
85
75
110
105
140
155
190
100
120
50
90
85
125
125
165
180
220
120
140
60
105
100
145
145
190
200
245
140
160
70
120
115
165
165
215
225
275
160
180
75
125
120
170
170
220
250
300
180
200
90
145
140
195
195
250
275
330
200
225
105
165
160
220
220
280
305
365
225
250
110
175
170
235
235
300
330
395
250
280
125
195
190
260
260
330
370
440
280
315
130
205
200
275
275
350
410
485
315
355
145
225
225
305
305
385
455
535
355
400
190
280
280
370
370
460
510
600
400
450
210
310
310
410
410
510
565
665
450
500
220
330
330
440
440
550
625
735
500
560
240
360
360
480
480
600
690
810
560
630
260
380
380
500
500
620
780
900
630
710
285
425
425
565
565
705
865
1005

 
 

Dimensions, tolerances

 
 

Dimension standards

imageref_17757201419_All.gif   The main dimensions of cylindrical roller bearings correspond to ISO 15:2017 (DIN 616:2000 and DIN 5412-1:2005).  
  The main dimensions of L-section rings HJ correspond to ISO 246:1995 (DIN 5412-1:2005).  
 

Chamfer dimensions

imageref_17757201419_All.gif   The limiting dimensions for chamfer dimensions correspond to DIN 620‑6:2004. Overview and limiting values   ➤ section. Nominal value of chamfer dimension ➤ dimension table.  
 

Tolerances

imageref_17757201419_All.gif   The dimensional tolerances of cylindrical roller bearings correspond to the tolerance class Normal, the running tolerance to the tolerance class 6 in accordance with ISO 492:2014. Tolerance values in accordance with ISO 492 ➤ Table .  
 

Suffixes

 
 

For a description of the suffixes used in this chapter ➤ Table 7 and medias interchange http://www.schaeffler.de/std/1D52.

 
   
Table 7
Suffixes and corresponding descriptions
 

Suffix
Description of suffix
C3
Radial internal clearance C3 (larger than normal)
Available
by agreement
C4
Radial internal clearance C4 (larger than C3)
C5
Radial internal clearance C5 (larger than C4)
E
Increased capacity design
Standard
EX
Increased capacity design, design modified
in accordance with standard (parts from these bearings must not be interchanged with parts from bearings
of the same size of the previous design E)
JP3
Sheet steel window cage, single-piece, roller-guided
Available
by agreement
J30P
Black oxide coated (Durotect B)
MPAX
Solid brass cage, single-piece, rib-guided on outer ring
MPBX
Solid brass cage, single-piece, rib-guided on inner ring
M1
Solid brass cage, two-piece, roller-guided
Standard
M1A
Solid brass cage, two-piece, rib-guided on outer ring
Available
by agreement
M1B
Solid brass cage, two-piece, rib-guided on inner ring
TB
Bearing with increased axial load carrying capacity (toroidal crowned design)
Standard, dependent on bearing size
TVP2
Solid window cage made from glass fibre reinforced polyamide PA66
Standard
XL
X-life bearing

 
 

Structure of bearing designation

 

Examples of composition of bearing designation

 

The designation of bearings follows a set model. Examples ➤ Figure 12 to ➤ Figure 14. The composition of designations is subject to DIN 623-1    ➤ Figure.

 
   

Figure 12
Single row cylindrical roller bearing with cage – bearing with non-locating bearing
_dictid_N2820_
function: designation structure


 

imageref_20347734539_en.gif

 
   

Figure 13
Single row cylindrical roller bearing with cage – bearing with semi-locating bearing
_dictid_S4260_
function: designation structure


 

imageref_20347736715_en.gif

 
   

Figure 14
Single row cylindrical roller bearing with cage, type NJ with L-section ring – bearing with locating bearing function: designation structure


 

imageref_20347738891_en.gif

 
 

Dimensioning

 
 

Equivalent dynamic bearing load

P = Fr under purely radial load of constant magnitude and direction

 

The basic rating life equation L = (Cr/P)p used in the dimensioning of bearings under dynamic load assumes a load of constant magnitude and direction. In radial bearings, this is a purely radial load Fr. If this condition is met, the bearing load Fr is used in the rating life equation for P (P = Fr).

 
 

Cylindrical roller bearings with non-locating bearing
_dictid_N2820_
function

P = Fr

 

Non-locating bearings can only support radial loads. For these bearings ➤ Equation 6.

 

Equation 6
Equivalent dynamic load
 
imageref_9007199294669579_All.gif

 

Cylindrical roller bearings with semi-locating or locating bearing function

P is a substitute force for combined load and various load cases

 

If the condition described above is not met, i.e. if, in addition to the radial force Fr, there is also an axial force Fa, a constant radial force must first be determined for the rating life calculation that (in relation to the rating life) represents an equivalent load. This force is known as the equivalent dynamic bearing load P.

 

Fa/Fr ≦ e or Fa/Fr > e

 

The calculation of P is dependent on the load ratio Fa/Fr and the calculation factors e and Y ➤ Equation 7 and ➤ Equation 8.

 

Equation 7
Equivalent dynamic load
 
imageref_19670284299_All.gif


Equation 8
Equivalent dynamic load
 
imageref_20339725195_All.gif

Legend

 
P
 N
Equivalent dynamic bearing load
Fr
 N
Radial load
Fa
 N
Axial load
e, Y
Factors ➤ Table 8.
 
   
Table 8
Factors e and Y
 

Bearing series
Calculation factors
e
Y
NJ2, NUP2, NJ3, NUP3, NJ4
0,2
0,6
NJ22, NUP22, NJ23, NUP23
0,3
0,4

 
 

Equivalent static bearing load

P0 = F0r

 

For cylindrical roller bearings subjected to static load ➤ Equation 9.

 

Equation 9
Equivalent static load
 
imageref_9007199294671243_All.gif

Legend

 
P0
 N
Equivalent static bearing load
F0r
 N
Largest radial load present (maximum load).
 
 

Static load safety factor

S0 = C0/P0

 

In addition to the basic rating life L (L10h), it is also always necessary to check the static load safety factor S0 ➤ Equation 10.

 

Equation 10
Static load safety factor
 
imageref_27021597814984331_All.gif

Legend

 
S0
Static load safety factor
C0
 N
Basic static load rating
P0
 N
Equivalent static bearing load.
 
 

Minimum load

 

In order to prevent damage due to slippage, a minimum radial load of P > C0r/60 is necessary during continuous operation

 

In order that no slippage occurs between the contact partners, the cylindrical roller bearings must be constantly subjected to a sufficiently high radial load. For continuous operation, experience shows that a minimum radial load of the order of P > C0r/60 is thus necessary. In most cases, however, the radial load is already higher than the requisite minimum load due to the weight of the supported parts and the external forces.

 
imageref_18348417035_All.gif   If the minimum radial load is lower than indicated above, please consult Schaeffler.  
 

Design of bearing arrangements

 

Support bearing rings over their entire circumference and width

 

In order to allow full utilisation of the load carrying capacity of the bearings and achieve the requisite rating life, the bearing rings must be rigidly and uniformly supported by means of contact surfaces over their entire circumference and over the entire width of the raceway. Support can be provided by means of a cylindrical seating surface. The seating and contact surfaces should not be interrupted by grooves, holes or other recesses. The accuracy of mating parts must meet specific requirements ➤ Table 9 to ➤ Table 12.

 
 

Radial location

For secure radial location, tight fits are necessary

 

In addition to supporting the rings adequately, the bearings must also be securely located in a radial direction, to prevent creep of the bearing rings on the mating parts under load. This is generally achieved by means of tight fits between the bearing rings and the mating parts. If the rings are not secured adequately or correctly, this can cause severe damage to the bearings and adjacent machine parts. Influencing factors, such as the conditions of rotation, magnitude of the load, internal clearance, temperature conditions, design of the mating parts and the mounting and dismounting options must be taken into consideration in the selection of fits.

 
imageref_17757187211_All.gif   If shock type loads occur, tight fits (transition fit or interference fit) are required to prevent the rings from coming loose at any point. Clearance, transition or interference fits ➤ Table and ➤ Table .  
 

The following information provided in Technical principles must be taken into consideration in the design of bearing arrangements:

 
   
 

Axial location

The bearings must also be securely located in an axial direction

 

As a tight fit alone is not normally sufficient to also locate the bearing rings securely on the shaft and in the housing bore in an axial direction, this must usually be achieved by means of an additional axial location or retention method. The axial location of the bearing rings must be matched to the type of bearing arrangement. Shaft and housing shoulders, housing covers, nuts, spacer rings, retaining rings, adapter and withdrawal sleeves etc., are fundamentally suitable ➤ Figure 15.

 
 

Dimensional, geometrical and running accuracy of cylindrical seats

A minimum of IT6 should be provided for the shaft seat and a minimum of IT7 for the housing seat

 

The accuracy of the cylindrical bearing seat on the shaft and in the housing should correspond to the accuracy of the bearing used. For cylindrical roller bearings with the tolerance class Normal, the shaft seat should correspond to a minimum of standard tolerance grade IT6 and in the housing seat to a minimum of IT7; with tolerance class 6, the shaft seat should correspond to a minimum of IT5 and the housing seat to a minimum of IT6. Guide values for the geometrical and positional tolerances of the bearing seating surfaces ➤ Table 9, tolerances t1 to t3 in accordance with    ➤ Figure. Numerical values for IT grades ➤ Table 10.

 
   
Table 9
Guide values for the geometrical and positional tolerances of bearing seating surfaces
 

Bearing
tolerance class
Bearing seating surface
Standard tolerance grades to ISO 286-1
(IT grades)
to ISO 492
to DIN 620
Diameter tolerance
Roundness tolerance
Parallelism tolerance
Total axial runout tolerance of abutment shoulder
t1
t2
t3
Normal
PN (P0)
Shaft
IT6 (IT5)
Circumferential load IT4/2
Circumferential load IT4/2
IT4
Point load IT5/2
Point load IT5/2
Housing
IT7 (IT6)
Circumferential load IT5/2
Circumferential load IT5/2
IT5
Point load IT6/2
Point load IT6/2
6
P6
Shaft
IT5
Circumferential load
IT3/2
Circumferential load
IT3/2
IT3
Point load
IT4/2
Point load
IT4/2
Housing
IT6
Circumferential load
IT4/2
Circumferential load
IT4/2
IT4
Point load
IT5/2
Point load
IT5/2

 
   
Table 10
Numerical values for ISO standard tolerances (IT grades) to ISO 286-1:2010
 

IT grade
Nominal dimension in mm
over
10
18
30
50
80
120
incl.
18
30
50
80
120
180
Values in μm
IT3
  3
4
4
5
6
8
IT4
  5
6
7
8
10
12
IT5
  8
9
11
13
15
18
IT6
  11
13
16
19
22
25
IT7
  18
21
25
30
35
40
continued ▼

 
   
Table 11
Numerical values for ISO standard tolerances (IT grades) to ISO 286-1:2010
 

IT grade
Nominal dimension in mm
over
180
250
315
400
500
630
incl.
250
315
400
500
630
800
Values in μm
IT3
  10
12
13
15
16
18
IT4
  14
16
18
20
22
25
IT5
  20
23
25
27
32
36
IT6
  29
32
36
40
44
50
IT7
  46
52
57
63
70
80
continued ▲

 
 

Roughness of cylindrical bearing seating surfaces

Ra must not be too high

 

The roughness of the bearing seats must be matched to the tolerance class of the bearings. The mean roughness value Ra must not be too high, in order to maintain the interference loss within limits. The shafts must be ground, while the bores must be precision turned. Guide values as a function of the IT grade of bearing seating surfaces ➤ Table 12.

 
   
Table 12
Roughness values for cylindrical bearing seating surfaces – guide values
 

Nominal diameter
of the bearing seat
d (D)
Recommended mean roughness value
for ground bearing seats
Ramax
mm
μm
Diameter tolerance (IT grade)
over
incl.
IT7
IT6
IT5
IT4
- 80
1,6
0,8
0,4
0,2
80
500
1,6
1,6
0,8
0,4
500
1 250
3,21)
1,6
1,6
0,8

 
 
______
 1    For the mounting of bearings using the hydraulic method, a value Ra = 1,6 μm must not be exceeded.
 
 

Mounting dimensions for the contact surfaces of bearing rings

The contact surfaces for the rings must be of sufficient height

 

The mounting dimensions of the shaft and housing shoulders, and spacer rings etc., must ensure that the contact surfaces for the bearing rings are of sufficient height. The transition from the bearing seat to the abutment shoulder must be designed with rounding to DIN 5418:1993 or an undercut to DIN 509:2006. Proven mounting dimensions for the radii and diameters of abutment shoulders are given in the product tables ➤ Figure 15 and ➤ dimension table. These dimensions are limiting dimensions (maximum or minimum dimensions); the actual values should not be higher or lower than specified.

 

Rib support in axially loaded bearings

 

Ribs under axial load must be supported over their entire height and entire circumference. The size and axial runout accuracy of the contact surfaces on the inner ring rib must be observed especially in the case of cylindrical roller bearings subjected to high loads, since these factors also influence the uniformity of the rib load and the running accuracy of the shaft. This means that the ribs may be subjected to damaging alternating stresses even in the case of very small misalignments. If the mounting dimensions indicated in the product tables are observed, the problems described can be reliably avoided ➤ dimension table.

 

Support in semi-locating bearings

 

In semi-locating bearings, it is sufficient to support the bearing rings on one side, on the rib supporting the axial load ➤ Figure 15.

 
   

Figure 15
Support of the inner ring rib – type NJ (semi-locating bearing)

dc =  recommended height of shaft shoulder with axially loaded rib
Arrow =  force flow

 

imageref_20352503307_All.gif

 
 

Mounting and dismounting

 
imageref_17757187211_All.gif   The mounting and dismounting options for cylindrical roller bearings, by thermal, hydraulic or mechanical methods, must be taken into consideration in the design of the bearing position.  

Since one bearing ring can be removed, the bearings are easy to mount.

 

Together with the cage and rollers, the bearing ring with the two rigid ribs forms a ready-to-mount unit. The other bearing ring can be removed. As a result, the bearing parts can be mounted separately from each other ➤ section . This gives simplified mounting of the bearings, especially when the two bearing rings have a tight fit.

 
 

Schaeffler Mounting Handbook

Rolling bearings must be handled with great care

 

Rolling bearings are well-proven precision machine elements for the design of economical and reliable bearing arrangements, which offer high operational security. In order that these products can function correctly and achieve the envisaged operating life without detrimental effect, they must be handled with care.

 
imageref_21602891659_en.gif   The Schaeffler Mounting Handbook MH 1 gives comprehensive infor­mation about the correct storage, mounting, dismounting and mainten­ance of rotary rolling bearings http://www.schaeffler.de/std/1D53. It also provides information which should be observed by the designer, in relation to the mounting, dismounting and maintenance of bearings, in the original design of the bearing position. This book is available from Schaeffler on request.  
 

Legal notice regarding data freshness

 

The further development of products may also result in technical changes to catalogue products

 

Of central interest to Schaeffler is the further development and opti­misation of its products and the satisfaction of its customers. In order that you, as the customer, can keep yourself optimally informed about the progress that is being made here and with regard to the current technical status of the products, we publish any product changes which differ from the printed version in our electronic product catalogue.

 
imageref_18350433803_All.gif   We therefore reserve the right to make changes to the data and illus­trations in this catalogue. This catalogue reflects the status at the time of printing. More recent publications released by us (as printed or digital media) will automatically precede this catalogue if they involve the same subject. Therefore, please always use our electronic product catalogue to check whether more up-to-date information or modification notices exist for your desired product.  
 

Further information

 

In addition to the data in this chapter, the following chapters in Technical principles must also be observed in the design of bearing arrangements:

 
   
   
  
Schaeffler applies cookies to secure an optimal use. With the further use of this website you accept the application of cookies.  Further information