Audi A8 D5 - Shielded Arc Plug Welding (SG Plug Welding)

Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not
permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
Equipment
Only equipment which is listed as approved in the workshop
equipment catalogue may be used.
Spot weld peel test
– To determine the required weld nugget diameter, establish the
setting parameters specified by the manufacturer and carry
out test using samples.
– Check all spot welds 100% by performing a chisel test.
High-quality spot welds peel off in the weld contact area; they do
not shear off.
– Calculate the weld nugget diameter according to the following
formula ("peel diameter") and carry out test on samples before
starting repair work.
Square root of T1 x 3.5 x 1.15
Note
T1 is the thinner panel of a pair of panels (e.g. pair of panels with
1.5 mm and 0.8 mm). Example: Square root of 0.8 x 3.5 x 1.15 =
3.6 mm weld nugget diameter. The narrow, welded test strip is
rolled or torn off the second sheet metal strip with a force applied
vertically to the surface of the metal.
Equipment
Only equipment which is listed as approved in the workshop
equipment catalogue may be used.
WARNING
♦ Always use an extraction system when performing weld‐
ing and grinding work.
♦ Welding and grinding must never be performed simulta‐
neously in the same working area.
♦ Working area must be cleaned at regular intervals as nec‐
essary to remove dust.
♦ Compressed air must NOT be used to blow out dust de‐
posits.
♦ The extraction system must be cleaned at regular inter‐
vals.
♦ In addition, the relevant accident prevention and industrial
safety regulations must be observed.
6.2 Shielded arc plug welding (SG plug
welding)
SG plug welds are primarily used where spot welds used as
standard cannot be restored for reasons such as limited acces‐
sibility.
It is essential to refer to the Workshop Manual for the relevant
vehicle in such cases.
General InformationBody Repairs, General Body Repairs - Edition 04.2018
24 6. Thermal joining techniques