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3
3,0
3,8
0,2
6,25
3,10
4
3,1
3,8
0,4
4,85
2,20
6
3,3
3,8
0,5
2,80
1,50
15. THE MOST COMMON MISTAKES IN MACHINE
CUTTING
Insufficient penetration of the cut, when cutting there is an excessive
amount of sparks on the upper side of the sheet. Possible causes:
1. The sheet has a dirty surface from rust or paint.
2. Consumables are worn. For optimal machine cutting, replace electrodes
and nozzles at the same time.
3. High cutting speed.
4. Current is set too low.
5. Large material thickness and improperly selected value of cutting current
and nozzle diameter.
Bad el. contact between the grounding clamp and the material.
The pilot arc will run, but there will be no ignition
5. There is poor electrical contact between the cut sheet and the ground
clamp.
6. Torch cutting height too high.
The cutting arc is unstable, goes out and „shoots“
1. Worn nozzle or electrode, replace both.
2. High air pressure.
3. Polluted air.
4. Uncaptured water condensate.
Caution
An unstable arc causes very intense interference, which can cause the machine
control system to collapse or endanger the surrounding equipment!
Conical cut
5. If there is a false cut turn off the machine, release the shield cup and rotate
the cutting tip about 1/4 and again try to cut.
6. Damaged nozzle and electrode, replace b
7. The position of the torch is not perpendicular to the material.
8. Too large distance from the cutting tip to the material
Caution
If the electrode is fired deeper than 1.5 mm, it must be replaced.
Scale on the underside of the cut
1. High air pressure.
