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Type and size of the load type and speeds
The loads and speeds to be used as the basis in the individual calculations must always be carried out with a computationally
constant value.
In practice, this prerequisite is often not fulfilled. In cases where loads or speeds are to be modified in a definable
time frame, partial calculation, e. g. of the service life, is possible. If changes in the temperatures, lubrication conditions
etc. have to be taken into consideration, this must also be included in the partial computation.
The figure shows modifiable forces and speeds, referred to individual time slices:
F
Select Selection ion of bearing design
Double row spherical roller bearings
The simplified bearing design of the double row spherical roller bearing is the single row spherical bearing supplied
by KRW.
Generally, double row spherical roller bearings are manufactured with 2 rows of spherical rollers with and without
guidance rims at the inner rings in several bearing designs and dimension ranges.
The bearing capacities are extremely high, depending on the bearing design. Axial forces are absorbed in both directions.
The angular movability can be used particularly in heavy machinery.
To simplify the assembly, particularly in the case of heavy bearings, double row spherical roller bearings with a conical
bore can be supplied, so that clamping or pulling sleeves, which are also a part of the product range of KRW,
can be used.
Double row spherical roller bearings cannot be disassembled.
Axial cylinder roller bearings
This bearing design has only a small space requirement. Large axial forces, even jerky load impact, can be absorbed.
However, the permissible speeds are relatively low. Since, because of geometry, a higher slip is present between rollers
and races, it is necessary to ensure a high quality lubrication.
Axial cylinder roller bearings can be dismantled.
Special bearings
In addition, KRW manufactures special designs of roller bearings on the basis of the above-mentioned bearing designs.
Special designs are mainly required if special properties of the roller bearing have to be derived from the deployment
conditions. KRW supplies electrically insulated bearings e.g. for electric locomotives, bearings with particularly
thin-walled cross-sections, e.g. for textile machinery, bearings with an ingenious construction for achieving
higher load absorption, e.g. for rolling mills, and lots more.
The overview of bearing designs and design versions therefore does not imply any limitations in the production and
supply capacities. KRW is specializing, more and more, in the production of tailored bearings and can thus fulfill
special customer requirements. An inquiry would be worthwhile in any case.
F
F 1
F min
F 2
F 3
If speed is constant, the only parameter to be modified is load.
t
F 4
F max
t
n
n 1
nn 2
t 1 t 2 t 3 t 4
Variable load with linear slope
Fmin + 2· F max
Fm = —————— —— [N]
3
nn 33
n 4
t