BOC Smootharc TIG185 AC/DC, Руководство по эксплуатации

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8.0 Troubleshooting and fault finding
Excessive electrode consumption
Cause Solution
Inadequate gas flow Increase gas flow
Inadequate post gas flow Increase post flow time to 1 sec per 10 amps
Improper size electrode for current required Use larger electrode
Operating of reverse polarity User larger electrode or change polarity
Electrode contamination Remove contaminated portion, then prepare again
Excessive heating inside torch Replace collet. Try wedge collet or reverse collet
Electrode oxidising during cooling Increase gas flow post time to 1 sec per 10 amps
Shielding gas incorrect Change to Argon (no oxygen or CO
2
)
Erratic Arc
Cause Solution
Incorrect voltage (arc too long) Maintain short arc length
Current too low for electrode size Use smaller electrode or increase current
Electrode contaminated Remove contaminated portion, then prepare again
Joint too narrow Open joint groove
Contaminated shield gas. Dark stains on the electrode or
weld bead indicate contamination
The most common cause is moisture or aspirated air in gas stream. Use welding grade gas only.
Find the source of the contamination and eliminate it promptly
Base metal is oxidised, dirty or oily Use appropriate chemical cleaners, wire brush, or abrasives prior to welding
Inclusion of tungsten or oxides in weld
Cause Solution
Excessive current for tungsten size used Reduce the current or use larger electrode
Accidental contact of electrode with puddle Maintain proper arc length
Accidental contact of electrode to filler rod Maintain a distance between electrode and filler metal
Using excessive electrode extension Reduce the electrode extension to recommended limits
Inadequate shielding or excessive drafts Increase gas flow, shield arc from wind, or change to gas saver or gas lens
Wrong gas Do not use ArO
2
or ArCO
2
GMAW (MIG) gases for TIG welding
Heavy surface oxides not being removed Use ACHF. Adjust balance control for maximum cleaning, or wire brush and clean the weld joint
prior to welding
Porosity in Weld Deposit
Cause Solution
Entrapped impurities, hydrogen, air, nitrogen, water vapour Do not weld on wet material.
Defective gas hose or loose connection
Check hoses and connections for leaks
Filler material is damp (particularly aluminium) Dry filler metal in oven prior to welding
Filler material is oily or dusty Replace filler metal
Alloy impurities in the base metal such as sulphur,
phosphorous, lead and zinc
Change to a different alloy composition which is weldable. These impurities can cause a
tendency to crack when hot
Excessive travel speed with rapid freezing of weld trapping
gases before they escape
Lower the travel speed
Contaminated shield gas Replace the shielding gas
26 BOC Smootharc TIG 185 AC/DC Operating Manual