Page 779 - Rollingbearings

Designs and variants
Relubrication of sealed bearings Diagram 1
When the required service life is longer than Grease life for sealed spherical roller bearings with designation sufix VT143 where
the grease life, the bearings may require P ≤ 0,067 C
relubrication A suitable grease quantity to
relubricate sealed bearings can be obtained
using
Grease life L [h]
10
G = 0,0015 D B 30 000
p
25 000
where
20 000
G = grease quantity [g] nd m = 25 000
p
D = bearing outside diameter [mm] 15 000
B = bearing width [mm] 75 000
50 000
10 000 100 000
The grease should be applied slowly through 125 000
the lubrication holes in the outer ring, pref- 8 000 150 000
erably while the bearing is rotating to avoid 175 000
damaging the seals. SKF recommends relu- 6 000 200 000
bricating with the same grease as the initial
ill 250 000
4 000

3 000

 WARNING 2 000
Seals made of FKM (luoro rubber)
exposed to an open lame or tempera-
tures above 300 °C (570 °F) are a health
and environmental hazard! They remain
dangerous even after they have cooled. 1 000
Read and follow the safety precau- 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115
tions on page 197. Operating temperature [°C]
n = rotational speed [r/min]
d = bearing mean diameter [mm]
m
= 0,5 (d + D)
9

Table 1
Technical speciications of SKF greases for sealed spherical roller bearings
Designa- Grease Temperature range 1) Thickener Base oil NLGI Base oil viscosity
tion type grade [mm 2 /s]
sufix at 40 °C at 100 °C
(105 °F) (210 °F)
–50 0 50 100 150 200 250 °C

VT143 LGEP 2 Lithium soap Mineral 2 200 16

GEM9 LGHB 2 Calcium complex Mineral 2 400 26,5
sulphonate
GLE LGWM 2 Calcium complex Mineral/ 2 80 8,6
sulphonate Synthetic
–60 30 120 210 300 390 480 °F

1) Refer to the SKF trafic light concept (page 117).

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