NU10/750 W33 Chamber Cages Steel Ball Bearings , Machine Tool Bearings With Rough Ground Inner Ring

The following combination specifications are common:
for NU + HJ: NUJ
for NJ + HJ: NH
for WU + HJ: WU..W

The bearing versions NU or NNU are used as examples of technical specifications such as load ratings and speed limits.

Cylindrical roller bearings are also available with a rough-ground inner ring raceway. You can also order bearings without an innerring (RNU) or without an outer ring (RN).

Equivalent dynamic load
The following applies to a cylindrical roller bearing with radial load:

P = F_r [kN]

If the radial force is combined with an axial force Fa, it will be considered in the bearing service life calculation, where F_a ≤ F_{a zul} admissible must be (F_aadmissible = admissible axial force).

Admissible axial load
Cylindrical roller bearings of the series NUP, NJ, NJ with angular rings (NH) and cageless bearings of the series NJ..VH, NCF..V and NNF..V may accept axial forces, if they are also loaded in radial direction. The maximum axial load admissible is



if



is ensured.

It depends on:

• radial load
• speed
• lubrication
• operating temperature and heat transfer conditions

The theoretical axial load is determined calculating the heat balance at the bearing positions, and may be estimated as follows:



F_a axial force [kN]

f_b 0,0048 for cage bearings
0,0063 for cageless bearings

d_m mean bearing diameter

n Inner ring speed [min^-1]

v operating viscosity of the oil or the grease basic oil [mm²/s]

D outer bearing diameter [mm]

d bore diameter [mm]

The axial clearance capacity depends on the support at the shoulders, and is limited by:



F_{a zul} zulässige Axialkraft [kN]

K 6,5 for single row cage bearings
5,5 for cageless single row bearings
3 for multiple row bearings

d_m mean bearing diamet

B bearing width [mm]

The axial clearance capacity depends on the support at the shoulders, and is limited by:

Shaft
Housing

d_w support diameter for inner ring [mm]

D_g support diameter for outer ring [mm]

F envelope diameter of the inner ring [mm]

J edge diameter of the inner ring [mm]

E envelope diameter of the outer ring [mm]

H edge diameter of the outer ring [mm]


If the admissible axial load is exceeded, the support diameter has to be larger.

Equivalent static load
The following applies to a cylindrical roller bearing with static radial load:


P₀ = F_r [kN]