Mitsubishi MOTORS Lancer Evolution VIII 2003, Technical Information Manual

Page: 212 / 368

WELDING
BASE OF BODY REPAIR 9-8
GAS SHIELD ARC WELDING
M4090003000010
Gas shielded arc welding is one method of arc weld-
ing. In this method, while the area to be welded is
shielded from the air by a layer of inert gas (such as
argon) or carbon dioxide gas, the filler metal (wire) is
fed from the torch nozzle at a constant rate and an
electric arc is generated between the tip of the wire
and the area being welded, thus generating heat to fuse the area. There are two types of gas shielded
arc welding, classified according to the gas they use
as the shield gas: carbon dioxide (CO2) gas shielded
arc welding, and MIG welding, which uses an inert
gas (such as argon).
However, herein we will refer to all gas shielded arc
welding as MIG welding.
MIG SPOT WELDING
This welding method is used in areas where regular
spot welding cannot be done. The two panels are
stacked together, the tip of the torch (one designed
for use in MIG spot welding) is positioned on one
side, an arc is generated for a short time, and a par-
tial melting is done to obtain a spot weld.
.
Procedure
CAUTION
•
Make sure that the area to be welded is per-
fectly clean; remove oxidation film, scales,
rust, dirt, etc.
•
The two panels to be welded must be in per-
fect contact with each other.
•
The number and pitch of the weld points
should be approximately the same as for the
factory welds.
1. Position the tip of the nozzle at a right angle to the
surface to be welded.
2. Being sure that the two prongs are not leaning to
either side, set them in direct contact with the
panel to the welded.
3. Welding will begin when the torch trigger is
squeezed, and will stop automatically when the
weld is complete.
.
AB200035
NOZZLE
WIRE
CONTACT TIP
METAL VAPOR
SHIELD GAS
AB
AB200036 AB200036 AB
WIRE
GAS CUP
GAS OUTLET