YATO YT-81352, Руководство пользователя

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OPERATION CONTROL AND CONNECTORS
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
Blowhole
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
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 falls off
and lose protection
Manipulation of electrode is not proper
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
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
Defect name Caused reasons Prevent methods
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.
Adjust the structure of welding material.
Adopt the basic electrode.
Cold crack
Three reasons will cause cold crack:
The structure turned from the marten site
The residual stress caused by big restraint
intensity
The residual hydrogen in welding gap.
Adopt low hydrogen type basic electrode.
Bake under the instruction before use.
Remove the feculence before use, reduce the
percentage of hydrogen
Adopt appropriate parameters and heat input
After welding, do dehydrogenation at once.
§4.6 Operation Environment
·Height above sea level is below 1000m.
·Operation temperature range:-10
0
C
̚
+40
0
C.
·Relative humidity is below 90 %( +20
0
C ).
·Preferably site the machine some angles above the floor level, the maximum angle
does not exceed 15
0
.
·Protect the machine against heavy rain or in hot circumstance against direct sunshine.
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