Page 219 - Rollingbearings

Bearing size
Fig. 1
Free circular motion vibrating screen

ω
R r

G

Fig. 2

Bearing arrangement

Bearing size SKF rating life
L 10mh = a SKF 10h
L
1. Lubrication condition – the viscosity ratio, κ

A shaft diameter of 140 mm is needed to transmit the required shaft κ = ν/ν
1
drive torque and limit shaft delection.
SKF supplies bearings in the 223 series for vibratory applications. The rated viscosity ν = 10 mm 2 /s (diagram 14, page 101).
1
Based on the required shaft diameter, the 22328 CCJA/W33VA405 A viscosity ratio, κ, of about 4 is targeted to operate in full ilm
is selected. We will check its size using the SKF rating life. lubrication conditions, therefore ν should be about 40 mm 2 /s.
Product data for 22328 CCJA/W33VA405 is on page 800. You need to verify the viscosity ratio after you have selected your
For vibrating screens, the equivalent dynamic bearing load, P, can lubricant.
be estimated using:
2. Contamination factor, η c
Given:
⎛ 1,2 × G × r × ω 2 w ⎛ 1,2 × 6 100 × 0,0081 × 79,2 2 w
P =
⎝
⎠
⎝ 2 = 2 ⎠
• contamination conditions are typical (i.e. open bearings, no ilter-
= 186 kN ing, wear particles and ingress from surrounding and harsh
environment) C.1 Vibrating screen
The load ratio C/P = 1 357/186 = 7,3 • d = 220 mm
m
then, using table 6, page 105, η = 0,2
c

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