aluminium in commercial vehicles - European Aluminium Association

EUROPEAN ALUMINIUM ASSOCIATION ALUMINIUM IN COMMERCIAL VEHICLES CHAPTER VIII 127
Chassis side members for
instance are usually fabricated
from two extrusions forming the
two flanges of the member and
a sheet for the web.
The assembly shown in Figure
VIII.6 can be automatically MIG
welded with two welding torches
operating simultaneously.
Both methods of butt joining are
possible, i.e. with the side member
positioned vertically or horizontally.
The choice of position
will be dictated chiefly by the
design of the welding bench.
When the side member is horizontal
a support will be needed
to counteract angular deflection.
FIGURE VIII.5
WELDING WITH SUPPORT PLATE
11.2.2. End stops
These must be positioned so as
to allow free elongation of the
assemblies during welding.
"Compressing" a weld, i.e. preventing
its elongation, greatly
exaggerates contraction and
hence subsequent deformation.
11.2.3. Predeforming
Some weld deformations can be
offset by predeforming the areas
to be welded in such a way that
the assembled components
"come right" after welding.
If the metal is only predeformed
in the elastic zone by clamping,
the results can be very erratic,
and it is therefore advisable to
predeform by bending the metal
in the plastic zone. In this way,
the results will be predictable
and repeatable.
FIGURE VIII.6
FABRICATING A CHASSIS MEMBER
‰
Vertical
(flat)
‰
Horizontal (flat)
‰
‰