6308-ZZ Deep groove ball bearings 40x90x23 mm

Deep groove ball bearings 6308-ZZ

Demension: 40X90X23mm,   weight:0.6kg.

1)Materials for rings and rolling elements

While the contact surfaces between the bearing rings and rolling elements are subjected to repeated heavy 

stress,they must still maintain high rotational precission,therefore, the materials used for bearings rings

and rolling elements require the following characteristics:

●High rolling contact fatigue strength

●High hardness

●High wear resistance

●High dimensional stability

●High mechanical strength

The material used by our companyis high carbonchromium bearings steel GCr15-GB/T18254 equivalent such as 

AISI52100(USA),DIN100Cr6(Germany) JISSUJ2(Japan) and BS534A99(UK).

2)Materials for cages

The materials for cages must have strength to with stand rotation at load and shock load. Low frictional efficiency light weight and be able to with stand operation temperature.

The material used in ribbon cages or crown cages is 08F or SPCC pressed.

It is chemical compositionis shown for extra-high speed application. Plastic cages such as glass reinforced polymideareused.

These plastic crown have the advantages oflow torque,long grease lefe and low noise,etc.

3)Vibration and noise

● The measuring parameter of vibration adopted by RNB is the vibration acceleration of vibration velocity.

● The measuring units and measuring method are specified by JB/T5314 and JB/T5313 In the process of

 measuring vibration strictly controlled noise by using acoustics.

4)Internal clearance

Single row deep groove ball bearings are manufactured with Normal radial internal clearanceas standard.

Most of the bearings are also available with C3 radial internal clearance. Some of the bearings can also be

supplied with as maller C2 clearance or the much greater C4 or C5 clearances. In addition, deep groove ball

bearings are available with reduced or displaced internal clearance ranges. These special clearances may 

use reduced ranges of standard clearance classes or partitions of adjacent classes, see designation suffix

CN insection.

5)Tolerances

Single row deep groove ball bearings are manufactured as standard to normal tolerances.

Single row deep groove ball bearings are produced to higher precision than the ISO Normal tolerances. The 

dimensional accuracy corresponds to P6 tolerances, expect the width tolerance,which is considerably tighter

and reduced to

-0/–60μm for bearings with outside diameter up to 110 mm
-0/–100 μm for larger bearings.

The running accuracy depend on the bearing size and corresponds to

-   P5 tolerances for bearings up to a 52mm outside diameter
-   P6 tolerances for bearings above 52 mm up to 110 mm outside diameter
-   Normal tolerances for larger bearings.

For bearing arrangements where accuracy is a key operational factor, some SKF single row deep groove ball 

bearings are also available with accuracy completely to P6 or P5 tolerance classs pecifications.The 

availability of these bearings should always be checked before ordering.

Deep groove ball bearings 6308-ZZ