Black welding spot
Welding spot is not prevented from oxidizing .User may check as following:
a)
Make sure the valve of argon cylinder is opened and its pressure is
enough. Argon cylinder must be filled up to enough pressure again if pressure
of cylinder is below 0.5Mpa .
b) Check if the flow meter is opened and has enough flow .User can choose
different flow according to welding current in order to save gas .But too small
flow maybe cause black welding spot because preventive gas is too short to
cover welding spot .
c)
Check if torch is in block.
d)
If gas passage is not air-tight or gas is not pure can lower welding quality.
e)
If air is flowing powerfully in welding environment, that can lower welding
quality.
Arc-striking is difficult and easy to pause
a) Make sure quality of tungsten electrode is high.
b) If the electrode is not dried, it will cause unstable arc, welding defect increases
and the quality is down.
c) If use extra-long cable, the output voltage will decrease, so please shorten the
cable.
Output current not to rated value
When power voltage departs from the rated value, it will make the output current
not matched with rated value; when voltage is lower than rated value, the max
output may lower than rated value.
Current is not stabilizing when machine is being operated
It has something with factors as following:
a) Electric wire net voltage has been changed.
b) There is harmful interference from electric wire net or other equipment
Gas vent in welds
a) Examine whether the gas supply circuit has leakage.
b) Examine whether there is sundries such as oil, dirt, rust, paint etc. on the
surface.
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