|
axles & bearings
SQUARE OR ROUND AXLES
For the same nominal size a
square axle is some 70% stronger than a round axle, yet only 27% heavier.
When fitted with brakes the square axle is better for transmitting
brake torque to the spring system as the axle seat sits flat on the
axle.
STEEL &
BEARING LOAD RATINGS
Three things
effect the strength of basic axle
1. the
diameter of the steel
2. the design
load of the bearings
3. the design
load of the spindle machining
STEEL SIZE
(4045 MATERIAL) |
MAXIMUM AXLE LOAD (tonnes) |
DISTANCE FROM CHASSIS TO TYRE CENTRELINE (mm)* |
|
39 round |
1.0 |
150 |
|
45 round |
1.3 |
170 |
|
40 square |
1.6 |
170 |
|
50 round |
1.5 |
190 |
|
45 square |
1.9 |
190 |
|
50 square |
2.6 |
200 |
|
60 round |
2.6 |
200 |
|
65 round |
3.3 |
200 |
* If the
chassis to tyre centreline is greater than shown the allowable axle
load is reduced in proportion
BEARINGS
|
BEARING
TYPE |
MAXIMUM
BEARING LOAD (tonnes) |
SPINDLE
LOAD (tonnes)
|
|
LM
(HOLDEN) |
1.7 |
1.3 |
|
SL
(FORD) |
1.8 |
1.8 |
|
SLM |
2.1 |
2.0 |
|
VT |
2.7 |
2.7 |
|
TF9 |
3.1 |
2.9 |
|
VC |
3.3 |
3.7 |
AXLE/BEARING SELECTION
The table below shows the optimum selection for
the given maximum loading in tonnes under normal operating
conditions.
| |
MAX TYRE DIA (mm) |
39 round |
45 round |
40 square |
50 round |
45 square |
50 square |
60 round |
65 round
|
|
LM (HOLDEN) |
630 |
1.0 |
1.3 |
1.3 |
1.3 |
1.3 |
|
|
|
|
SL (FORD) |
710 (790) |
|
1.3 (1.2) |
|
1.5 (1.4) |
1.8 (1.6) |
1.8 (1.6) |
|
|
|
SLM |
710 (790) |
|
|
|
1.5 (1.4) |
1.9 (1.7) |
2.0 (1.8) |
|
|
|
VT |
790 |
|
|
|
|
|
2.6 |
2.6 |
|
|
TF9 |
790 |
|
|
|
|
|
2.6 |
2.6 |
|
|
VC |
790 |
|
|
|
|
|
|
2.6 |
3.3 |
|
1.0
|
PREFERRED |
|
1.3
|
NON- PREFERRED |
Keeping to
preferred sizes offers best strength.
All information has been reproduced
with the kind permission of Vehicle Components
Vehicle Components website
PARTS of a BEARING
Bearings comprise of two
parts...........
* the cup which is pressed into the hub.
* the cone which is the part that contains the rollers of the
bearing.
The bearing on the inside of the hub flange, the side closest to the
centre of the trailer, is called the inner bearing.
The bearing on the outside is called the outer bearing.
Bearings should always be
replaced in a set, the cup & cone together.
info by Rob |
