Fronius MTG 400i K4 Bedienungsanleitung Seite 43

Poor-quality weld properties
Cause: Incorrect welding parameters
Remedy: Correct settings
Cause: Poor ground earth connection
Remedy: Establish good contact with workpiece
Cause: Too little or no shielding gas
Remedy: Check pressure regulator, gas hose, gas solenoid valve and welding torch
gas connection. For gas-cooled welding torches, check gas seal, use suitable
inner liner
Cause: Welding torch leaks
Remedy: Replace welding torch
Cause: Excessively large or heavily worn contact tip
Remedy: Change contact tip
Cause: Incorrect wire alloy or incorrect wire diameter
Remedy: Check the inserted wire spool/basket-type spool
Cause: Incorrect wire alloy or incorrect wire diameter
Remedy: Check the weldability of the parent materials
Cause: Shielding gas not suitable for wire alloy
Remedy: Use correct shielding gas
Cause: Unfavorable welding conditions: Shielding gas contaminated (moisture, air),
inadequate gas shield (weld pool "boiling", draft), impurities in the workpiece
(rust, paint, grease)
Remedy: Optimize welding conditions
Cause: Welding spatter in the gas nozzle
Remedy: Remove welding spatter
Cause: Turbulence due to excessively high quantity of shielding gas
Remedy: Reduce quantity of shielding gas; recommended:
shielding gas quantity (l/min) = wirespool diameter (mm) x 10
(for example 16 l/min for 1.6 mm wire electrode)
Cause: Excessively large distance between welding torch and workpiece
Remedy: Reduce distance between welding torch and workpiece (approx. 10–15 mm/
0.39–0.59 in.)
Cause: Excessively large work angle of the welding torch
Remedy: Reduce work angle of the welding torch
Cause: Wirefeed components do not correspond to the diameter of the wire elec-
trode/the material of the wire electrode
Remedy: Use correct wirefeed components
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