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Warning:For safety while maintaining the machine,please shut off the
supply power and wait for 5minutes,until capacity voltage already drop
to safe voltage 36V!
Observe that whether panel knob and switch in the front and at the
back of arc welding machine are flexible ane put correctly in place.If
the knob has not been put correctly in place, please correct, If you can’t
correct or fix the knob, please replace immediately
If the switch is not flexible or it can’t be put correctly in place, please
replace immediately; Please get in touch with maintenance service
department if there are no accessories
After turn-on power, watch/listen to that whether the arc welding
machine has shaking, whistle calling or peculiar smell. If there is one
of the above problems, find out the reason to get rid of, if you can’t
find out the reason, Please contact local this area agent or the branch
company
Observe that whether the display value of LED is intact. If the
display number is not intact, please replace the damaged LED. If it still
doesn’t work, please maintain or replace the display PCB
Observe that whether the min/max value on LED accords with the set
value.If there is any difference and it has affected the normal welding
craft, please adjust it
Check up that Whether fan is damaged and is normal to rotate or control
. If the fan is damaged,please change immediately.If the fan does not
rotate after the arc welding machine is overheated, observe that whether
there is something blocked in the blade,if it is blocked,please get rid of;
If the fan does not rotate after getting rid of the above problems, you can
poke the blade by the rotation direction of fan.If the fan rotates normally,
the start capacity should be replaced; If not, change the fan
Observe that whether the fast connector is loose or overheated. If
the arc welding machine has the above problems,it should be fastened
or changed
Observe that Whether the current output cable is damaged. If it is
damaged, it should be wrapped up, insulated or changed
Using the dry compressed air to clear the inside of arc welding machine.
Especially forclearing up the dusts on radiator, main voltage transformer,
inductance, IGBT module, the fast recover diode and PCB, etc
Check up the bolt in arc welding machine,if it is loose,please screw
down it.If it is skid, please replace.If it is rusty,please erase rust on bolt
to ensure it works well
Whether the actual current accords with the displaying value.If they
does not accord, they should be regulated.The actual current value can
be measured by the adjusted plier-type ampere meter
Measure the insulating impedance among the main circuit,PCB and
case, if it below 1MΩ,insulation is thought to be damaged and need to
change, and need to change or strengthen insulation
Date
Daily
examination
Monthly
examination
Quarter-
yearly
examination
Yearly
examination
Maintenance item
4.1 Maintenance
In order to guarantee that arc welding machine works high-efficiently and in safety,it must
be maintained regularly.Let customers understand the maintenance methods and means
of arc welding machine more, enable customers to carry on simple examination and
safeguarding by oneself,try one’s best to reduce the fault rate and repair times of arc
welding machine, so as to lengthen service life of arc welding machine.Maintenance
items in detail are in the following table.
WELDING TECHNIQUE
AND
MAINTENANCE
Establishing the Arc and Making Weld Beads
Before attempting to weld on a finished piece of work, it is recommended that practice welds
be made on a sample metal of the same material as that of the finished piece.
The easiest welding procedure for the beginner to experiment with MIG welding is the flat
position. The equipment is capable of flat, vertical and overhead positions.
For practicing MIG welding, secure some pieces of 1.6 mm or 5.0 mm (1/16" or 3/16") mild
steel plate 150 mm x 150 mm (6" x 6"). Use 0.9 mm (.035") flux cored gasless wire or a solid
wire with shielding gas.
Setting of the Power Source
Power source and Wirefeeder setting requires some practice by the operator, as the welding
plant has two control settings that have to balance. These are the Wirespeed control (refer
to section 3.06.4) and the welding Voltage Control (refer to section 3.06.10). The welding
current is determined by the Wirespeed control, the current will increase with increased
Wirespeed, resulting in a shorter arc. Less wire speed will reduce the current and lengthen
the arc. Increasing the welding voltage hardly alters the current level, but lengthens the arc.
By decreasing the voltage, a shorter arc is obtained with a little change in current level.
When changing to a different electrode wire diameter, different control settings are required.
A thinner electrode wire needs more Wirespeed to achieve the same current level.
A satisfactory weld cannot be obtained if the Wirespeed and Voltage settings are not adjusted
to suit the electrode
wire diameter and the dimensions of the work piece.
If the Wirespeed is too high for the welding voltage, “stubbing” will occur as the wire dips
into the molten pool and does not melt. Welding in these conditions normally produces a
poor weld due to lack of fusion. If, however, the welding voltage is too high, large drops will
form on the end of the wire, causing spatter. The cor- rect setting of voltage and Wirespeed
can be seen in the shape of the weld deposit and heard by a smooth regular arc sound. Refer
to the Weld Guide located on the inside of the wirefeed compartment door for setup information.
Electrode Wire Size Selection
The choice of Electrode wire size and shielding gas used depends on the following:
Thickness of the metal to be welded
Type of joint
Capacity of the wire feed unit and Power Source
The amount of penetration required
The deposition rate required
The bead profile desired
The position of welding
Cost of the wire
WELDING TECHNIQUE
AND
MAINTENANCE
Maintenance
MIG Welding
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