EN
7.4
ALUMINIUM WELDING
To MIG weld aluminium, use the following:
1.
100% Argon shielding gas.
2.
Filler wire with a composition suited to the base welding ma-
terial. To weld ALUMAN and ANTICORODAL use 3-5% sili-
con wire.To weld PERALUMAN and ERGAL use 5%
magnesium wire.
3.
Use a torch designed for aluminium welding.
7.5
SPOT WELDING
This type of welding is used for spot welding two
overlapping sheets, and requires the use of a special gas nozzle.
Fit the spot welding gas nozzle, press it against the piece to be
welded. Press the torch button; note that the welder will eventually
detach from the piece. This time period is fixed by the TIMER con-
trol (Ref. 5 - - Picture 3 Page 5. - - Picture 2 Page 5., and must
be set depending on the thickness of the material. Operating only
FAULT
UNEVEN LEVEL
EXCESS THICKNESS
INSUFFICIENT METAL
OXIDISED BEAD
INSUFFICIENT
PENETRATION
OVER PENETRATION
LACK OF FUSION
CHANNELS
9.0
GENERAL MAINTENANCE
DISCONNECT THE POWER SOURCE FROM THE MAINS BE-
FORE PERFORMING ANY MAINTENANCE WORK.
Every 5-6 months, remove accumulated dust from the inside of
the welding unit with a jet of dry compressed air (after removing
side panels).
BE EXTREMELY CAREFUL TO AVOID BENDING MOVE-
MENTS, WHICH COULD DAMAGE AND CHOKE THE TORCH.
NEVER MOVE THE POWER SOURCE BY PULLING THE
TORCH.
PERIODICALLY CHECK the condition of the torch, which is the
part most subject to wear.
MIG WELDING FAULTS
APPEARANCE
with selector (Ref. 1 - - Picture 3 Page 5. - - Picture 2 Page 5.)
set to position
8.0
MIG WELDING FAULTS
FAULT CLASSIFICATION AND DESCRIPTION
MIG welds may be affected by various defects, which are impor-
tant to identify. These faults do not differ in form or nature from
those encountered during manual arc welding with coated elec-
trodes. The difference between the two applications lies rather in
the frequency of defects: porosity, for example, is more common
in MIG welding, while inclusion of slag is only encountered in
welding with coated electrodes.
The causes and prevention of faults are also quite different.
The following table illustrates the various faults.
CAUSE AND REMEDY
- Poor preparation.
- Align edges and hold during spot welding.
- No-load voltage or welding speed too low.
- Incorrect torch inclination.
- Wire diameter too large.
- Welding speed too high.
- Welding voltage too low for welding application.
- Weld in the channel if using a long arc.
- Regulate voltage.
- Wire is bent or over-protruding from the wire guide tube.
- Incorrect wire feed speed.
- Incorrect torch inclination.
- Irregular or insufficient distance.
- Wire guide tube worn.
- Wire speed too slow for voltage used or for welding speed.
- Wire speed too high.
- Incorrect torch inclination.
- Excessive distance.
- Distance too short.
- Rough out or grind the weld, then repeat.
- Welding speed too high.
(This fault is easily detected on sight by the welder, and should be cor-
rected immediately.)
9.1
TORCH MAINTENANCE
7 EN