Ronch Ronch Weld 315MAX, User Manual

Page: 21 / 29

21
Defect
name
Caused reasons Prevent methods
Welding
seam
doesn’t
meet the
requirement
The groove angle is not proper
The root face and assembly gap is
not equal
Welding technics parameters are
unreasonable
The welder’s operation skill is lower Choosing the proper groove angle &
assembly gap, improve the assembly
quality
Choosing the proper welding
parameters
Improve the operation skill of welders
Undercut
Over current
Arc length is too long
The electrode angle is wrong
Manipulation of electrode is not
proper
Choosing the proper welding current
& speed
The arc can’t be drawn too long
The electrode angle should be proper
Manipulation of electrode should be
correct
Incomplete
penetration
The groove angle or gap is too small,
the root face is too big
Welding parameters are not
suitable, or the assembly is not good
The welder’s operation skill is lower
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
Incomplete
fusion
The welding thermal input is too low
The arc direction is lean
There are rust & dust on the side of
groove
The slag between the layers is not
cleared well
Correctly to choose the welding
parameters
Operation seriously
Enhance the clearness of layers
Inclusion &
slag
inclusion
The slag clears bad in the middle
layer in the welding process
Under current or over speed in the
welding
Welding operation is not proper
The welding material can not match
the work piece
The groove design & processing are
not proper
Choosing the electrode of good slag
detachability
Strictly to clear the slag in the layers
Correctly to choose the welding
parameters
Adjusting the electrode angle and
manipulation way
Hot crack
In the process of solidification, the
inter crystal segregation is seriously
caused. At the same time, with the
effect of welding stress, the hot
crack is formed. Strictly control the percentage of S
and P in welding material.
Adjust the structure of welding
material.
Adopt the basic electrode.