Arc Welding Defect And Prevent Method - gala gar SMART PRO 5.0 Manual Técnico De Instrucciones

4.5 Arc Welding Defect and Prevent Method

Defect
Caused reasons
name
The groove angle is not proper
Welding
The root face and assembly gap is
seam
not equal
doesn't
Welding technics parameters are
meet the
unreasonable
requirement
The welder's operation skill is lower
Over current
Arc length is too long
Undercut The electrode angle is wrong
Manipulation of
proper
The groove angle or gap is too small,
the root face is too big
Incomplete
Welding parameters are not suitable,
penetration
or the assembly is not good
The welder's operation skill is lower
The welding thermal input is too low
The arc direction is lean
Incomplete There are rust & dust on the side of
fusion groove
The slag between the layers is not
cleared well
The temperature of molten pool is too
Overlap high
The liquid metal concretes slowly
The crater time lasts too short
Crater Over current in the welding of thin
plate
There are some dust like oil, rust or
water on the work piece surface and
groove
The coating of electrode is damped&
is not drying
Blowhole
Under current or over speed in the
welding
The arc is too long or lean burning,
the molten pool protection is not good
Over current, the coating of electrode
SMART PRO 5.0
Prevent methods
Choosing the proper groove angle &
assembly gap, improve the assembly
quality
Choosing
parameters
Improve the operation skill of welders
Choosing the proper welding current &
speed
The arc can't be drawn too long
The electrode angle should be proper
electrode is not
Manipulation of electrode should be
correct
Correctly to choose and process the
groove size
Correctly to assemble and ensure
clearance
Choosing the suitable welding current
& speed
Improve the operation skill of welders
Correctly
parameters
Operation seriously
Enhance the clearness of layers
Choosing parameters based on the
welding different position
Strictly to control the molten hole size
In the crater, electrode should be
stayed for a short time or round to
manipulate electrode
after the molten pool is filled in by
metal, take to the side for crater
Clear out the dust around groove for
about 20～30mm
Strictly to dry the electrode according
to manual
Correctly to choose parameters and to
operate
Using the short arc operation
Welding operation in the field should
have anti-wind protection
Don't use the invalid electrode
the proper welding
to choose the welding
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