WELDING
BASE OF BODY REPAIR
9-9
FEATURES OF MIG SPOT WELDING
In comparison to resistance spot welding, MIG spot
welding has the following advantages and disadvan-
tages.
.
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 • CO
2
(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.)
Re-repairability
(cutting away welded
area)
Difficult
(Much welding trace High hardness
of weld points)
Easy
(Can be separated by spot cutter.)
AB200037
AB
SWIVEL TIP
To Next Page
Loading...
