Mitsubishi Outlander XL. Manual - part 37

 

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Mitsubishi Outlander XL. Manual - part 37

 

 

Galvanized steel plate (SECC)

If  the  total  thickness  of  the  plates  at  the  weld
places  is  3  mm  (0.1  inch)  or  more,  use  plug
welding,  because  spot  welding  will  not  provide
sufficient welded strength.

Panel
thickness*
[mm (in)]

Number of repair weld (percentage of factory weld)

Safety
equipme
nt area

0.9  (0.04)  or
less

100% Same number as factory welds

1.0 (0.04)

200% Maintain pitch of at least 18 mm (0.7 inch); if not possible, plug weld.

1.2  (0.05)  or
more

100% Same number as factory welds; plug welding

Other
area

0.9  (0.04)  or
less

100% Same number as factory welds

1.0 (0.04)

140% Maintain pitch of at least 18 mm (0.7 inch); if not possible, plug weld.

1.2  (0.05)  or
more

100% Same number as factory welds; plug welding

NOTE: 

*: For welding steel plates of different

thicknesses, conform to the welding conditions for
the thinner plate.

USING A TEST PIECE TO CHECK NUGGET FORMATION

ZB6001980000

Weld point

1

2

3

Weld a test piece of the same type of steel plate as the panels
to be welded. Try to twist the piece, and also check the nugget
diameter.
Using  the  weld  point  as  an  axis,  apply  force  in  the  direction
indicated  by  the  arrows  in  the  illustration,  and  determine  the
strength of the weld.

1.

Good (The welded part remains at one side).

2.

and 3.
The  weld  conditions  are  unsatisfactory;  adjust  the  welding
current,  the  current  application  time,  and/or  the  applied
pressure.

CHECKING NUGGET STRENGTH FOLLOWING SPOT
WELDING

ZB6001990000

3 mm (0.1 in)

Stop  wedging  the  tip  or  the  chisel  or  flat-tipped
screwdriver  as  soon  as  the  size  of  the  nuggets  can  be
determined;  do  not  wedge  it  in  more  than  30  mm  (1.2
inches).

After  checking  the  nugget  diameter,  correct  the  place
where the checking was done.

Wedge the tip of a chisel or flat-tipped (-) screwdriver into the
space between two weld points.

The nuggets should not break apart.

BASE OF BODY REPAIR

9-7

WELDING

The nugget diameter should be 3 mm (0.1 inch) or more.

GAS SHIELD ARC WELDING

M40900000030USA0000010000

ZB600200

Nozzle

Wire

Contact tip

Metal vapor

Shield gas

0000

Gas  shielded  arc  welding  is  one  method  of  arc
welding. 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

ZB600201 

Gas cup

Gas outlet

Wire

0000

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 partial melting
is done to obtain a spot weld.

Procedure

Make sure that the area to be welded is perfectly
clean; remove oxidation film, scales, rust, dirt,
etc.

The two panels to be welded must be in perfect
contact with each other.

9-8

BASE OF BODY REPAIR

WELDING

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.

FEATURES OF MIG SPOT WELDING
In comparison to resistance spot welding, MIG spot
welding  has  the  following  advantages  and
disadvantages.

Item

Mig spot welding

Electric resistance spot welding

Working
characteristics

Light weight

Welding  possible  at  various
positions  (no  limit  upon  welding
positions)

Although

 the

 torch

 with

 separate

transformer  is  lightweight,  the  torch
combined with transformer type is heavy.

The arm must be exchanged to conform to
the weld location.

Weld time/point

Slow (0.5 second or more)

Fast (0.5 second or less)

Treatment

 after

welding

Necessary (grinding by grinder, etc.) Unnecessary

Power

High voltage, low current
(15 - 30 V, 50 - 200 A)

Low voltage, high current
(2 - 4 V, 4 - 10 kA)

Flux material

CO2(carbonic acid gas)

Weld wire

Unnecessary

Weld

 points/10

minutes
(rate of use)

25 points or less

Arc instability and contact tip burn
if rate of use is exceeded.

50 - 60 points

Welding  rod  deformation  and  transformer
overheating if rate of use is exceeded.

Distortion  caused  by
welding

Occurs easily

Rare

Welding strength

Depends on strength of welding wire
itself.

Same as base material

Little oxidation

Uniform welding quality

Weld traces

Button head (slightly convex)

Slight concave
(Almost no indentation if swivel tip used.)

ZB6002020000

Swivel tip

Re-repairability
(cutting  away  welded
area)

Difficult
(Much welding trace High hardness
of weld points)

Easy
(Can be separated by spot cutter.)

BASE OF BODY REPAIR

9-9

WELDING

ZB600203 0000

The MIG welding done around the doors, wheelhouse arches,
etc., to prevent the flanges from coming undone after hemming
work is also called MIG spot welding.

PLUG WELDING

ZB600204 0000

Torch

Perfect
contact

5 – 6 mm
(0.2 in)
diameter
hole

In order to prevent the formation of blowholes, fill in each
hole completely in one pass.
Be sure that the two panels are in perfect contact.
Be sure that the penetration goes all the way to the bottom
panel.
Plug welding is done by making holes 5 - 6 mm (0.2 inch) in
diameter in one of the panels to be welded together, positioning
the torch at a right angle to the holes and then filling in the holes
one at a time.

CONTINUOUS WELDING

ZB6002050000

There are several types of continuous welding: fillet (lap joint)
welding, butt welding, T joint welding, gap welding, etc.; these
are called short-circuit arc welding, and provide a stable arc at
a relatively low current.

 

Torch angle and welding technique
There  are  two  welding  techniques:  forehand  welding  and
backhand welding.

Forehand welding: Penetration is shallow and the bead is flat.
Backhand welding: Penetration is deep and the bead has a
convex shape.

9-10

BASE OF BODY REPAIR

WELDING

 

 

 

 

 

 

 

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