Self-Study Program

52
After the raw body shell has been finished
and the heat treatment has been carried out,
the body is cleaned and prepared with a
3-cation phosphating layer (Zn = zinc,
Ni = nickel, Mg = manganese) that forms a
bonding layer for the subsequent
cataphoretic immersion painting (CIP).
By modifying the phosphating (addition of
fluorides) it is possible to pre-treat fully
galvanised steel and aluminium bodies
together.
The subsequent stages of CIP painting, filler
and finish coating are identical for all bodies.
Any reworking required due to faults in the
paintwork is treated in the same way on
aluminium bodies as it is on galvanised steel
bodies.
All body types are driven together over the
same painting system.
Pre-treatment of sheet metals: cleaning and
degreasing
The first stage of the painting process in
production is to clean and degrease the raw
body shell. The raw body shell is immersed in
a cleaning tank and then sprayed with a
degreasing solution.
After rinsing and drying all of the grease
residue on the body has been removed.
Phosphating
During phosphating the body is immersed in
tanks with various phosphate salt solutions.
This produces a metal-phosphate crystalline
layer on the body metal. This means:
optimised adhesion layer and anti-corrosion
protection
SSP239_067
SSP239_064
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Painting