Stealth DIGI-ARC 160PFC MV, Operator'S Manual

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STEALTH DIGI-ARC 160PFC MV
16
OPERATION CONTROL AND CONNECTORS
13
diameter. The basic electrode’s arc length is not beyond the electrode diameter,
it’s better to choose the short arc welding; the acid electrode’s arc length is equal
to the electrode diameter.
§
4.5 Arc Welding Defect and Prevent Method
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
Overlap
The temperature of molten pool is too high
The liquid metal concretes slowly
Choosing parameters based on the welding
different position
Strictly to control the molten hole size
Crater
The crater time lasts too short
Over current in the welding of thin plate
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
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 Choosing the electrode of good slag
detachability
OPERATION CONTROL AND CONNECTORS
14
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 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.
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.
●
The content of dust, acid, corrosive gas in the surrounding air or substance can not
exceed normal standard.
●
Take care that there is sufficient ventilation during welding. There is at least 30cm
free distance between the machine and wall.
§4.7 Operation Notices
●
Read §1 carefully before attempting to use this equipment.
●
Connect the ground wire with the machine directly
●
In case closing the power switch, no-load voltage may be exported. Do not touch
the output electrode with any part of your body.
●
Before operation, no concerned people should be left. Do not watch the arc in