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Note: Most POROSITY is caused by gas problems, followed by base metal contamination
TROUBLESHOOTING: GENERAL GUIDE
Possible Solutions
Check that the feed roll size is correct for the wire size being used.
Increase the drive roll pressure until the wire feed is even. Do not apply
excessive pressure as this can damage the wire surface, causing copper
coating to loosen from steel wires or metal shavings to be formed from
soft wires like aluminum. These metal fragments or shavings can be
drawn into the wire feed conduit and will rapidly clog the gun liner.
When welding with fl ux-cored wires, excessive drive roll pressure may
open the wire seam and allow fl ux or metal powders to escape.
a. Dust, particles of copper, drawing lubricants, metal or fl ux and
other forms of contamination can all clog the gun liner so that the
wire feed is slowed or impeded. A liner that has been in use for an
extended period of time becomes worn and fi lled with dirt and
must be replaced.
b. When changing the welding wire, remove the swanneck from the
front end of the gun and blow out the gun liner with clean, dry
compressed air from the back of the gun. Repeat with the neck
liner.
Note: Wear safety goggles when using compressed air to
clean the liners. Make sure proper safety procedures are fol-
lowed
in order to avoid possible serious eye injury.
Check the lengths of the neck and gun liners and trim or replace if too
long or too short. The effi cient feeding of the welding wire is dependent
on the liners fi tting correctly. Consult the liner installation instructions on
pages 2-6 or contact your local Authorized ABICOR Binzel Distributor
for additional help.
An unprotected coil of wire quickly collects dust and other airborne
contamination. If grinding is being performed in the vicinity, particles
can become attached to the wire, severely interfering with the wire feed.
Replace with clean wire and keep it protected with a cover. Make sure
spare wire rolls are stored in a clean, dry place.
Set the brake so that the coil immediately stops rotating as soon as
welding is interrupted. If the brake is applied too hard it will cause the
feed rolls to slip, resulting in uneven wire feed. If it is too loose, overrun
of the wire will occur, causing wire tangles, inconsistent tension on the
feed mechanism and irregular arc characteristics.
Set the wire feed in relation to the arc voltage in such a way that the arc
is stable and burns evenly. In spray arc welding, set the wire feed so that
there are no short circuits and the fi ller metal is transferred in a spray
across the arc.
Find the cause of the interference and correct it. (See above)
When the internal diameter of the contact tip becomes worn from the
passage of wire through it, the wire may no longer stay in continuous
electrical contact with the tip. This results in an unstable arc and an
increase in spatter.
Paint, mill scale, silicon scale, rust or fl ux deposits from previous weld
runs may form an insulating layer causing an unstable arc. Clean the
surfaces to be welded.
Securely attach the ground cable as close to the point of welding as pos-
sible on the workpiece. Clean the surfaces thoroughly to ensure good
contact.
Check to insure the welding power connection on the power source is
tight, the connection on the wire feeder is tight, the connection to the
adaptor block is tight, and the connection of the gun to the adaptor
block is tight.
Adjust the contact tip to work distance to a minimum of 3/8” for short
arc welding. A more precise distance is 15 times the wire diameter.
Problems/Causes
ERRATIC WIRE FEED
Slipping feed rolls.
Clogged or worn gun
liner.
Liners too long or too
short.
Spatter on wire.
Coil brake incorrectly
adjusted.
UNSTABLE ARC
Incorrect setting of voltage
and/or current.
Problems in wire feeding.
Worn contact tip.
Impurities on the base
metal.
Poor contact between
ground cable and work-
piece.
Loose power connection
Stick-out too long.
Causes of Porosity
BASE METAL CONTAMINATION
Impurities on base metal.
FILLER METAL CONTAMINATION
Impurities on fi ller metal (wire).
ATMOSPHERIC CONTAMINATION
Drafts, wind, fans, etc.
GAS MIXING APPARATUS
1. Too high a gas fl ow, causing turbulence,
and/or sucking air at hose connections;
creating venturi effect at end of gas nozzle.
2. Too low a gas fl ow, causing insuffi cient gas
coverage.
3. Damaged or kinked gas lines.
4. Too high an oxygen content.
5. Leaks in gas distribution system.
6. Other impurities in gas – moisture, etc.
7. Inconsistent gas fl ow (cfh) at the torch
connection.
GAS TURBULENCE
1. Excessive spatter build-up in gas nozzle and
on contact tip.
2. Nozzle damage, causing uneven gas
coverage.
3. Torch gas ports clogged or deformed.
4. Super-heated nozzle, causing shielding gas
to expand rapidly and create return effect at
end of nozzle. Results in contamination of
gas by atmosphere.
5. Gas diffuser/nozzle insulator missing.
6. Too high a gas fl ow causing venturi effect.
WELDING PARAMETERS, ETC.
1. Too long a wire stick-out; gas nozzle too far
from weld puddle.
2. Bad torch position – too sharp a torch incline
causing venturi effect at the end of the nozzle
leading to atmospheric contamination.
3. Excessively wide weld pool for nozzle I.D.
4. Arc voltage too high.
5. Too high a travel speed.
Possible Solutions
a. Remove contamination; clean surfaces b.
Use of specifi c wire/gas mix for specifi c
types of impurities.
a. Replace wire.
b. Install wire-cleaning system.
c. Prevent industrial dust/dirt/grit from
contaminating wire during storage or use.
d. Prevent build-up of aluminum oxide on
exposed aluminum wire surface by using up
quickly.
e. Remove wire from wire drive unit and store
in a sealed plastic bag when not in use for
long
periods.
a. Protect weld from drafts (curtains/screens).
b. Use tapered or bottleneck gas nozzles when
drafts cannot be avoided.
1a. Reduce gas fl ow.
1b. Tighten all hose connection points.
2. Increase gas fl ow.
3. Repair or replace
4. Adjust mixer.
5. Repair leaks.
6. Overhaul system; fi t fi lters and/or dryers.
7. Regulate pressure into fl ow meter for
consistent cfh delivery of gas.
1. Clean nozzle and tip regularly; spray with
anti-spatter
fl uid.
2. Replace nozzle.
3. Clean or replace.
4. Check duty cycle rating of torch.
5. Replace.
6. Reduce gas fl ow.
1. Use longer nozzle or adjust stick-out (3/8”
minimum or 15 times wire diameter).
2. Correct torch angle.
3. Width of the weld pool should be 1.3 times
nozzle I.D.; use suitable wider gas nozzle.
4. Reduce voltage.
5. Reduce speed.
TROUBLESHOOTING: POROSITY (SUMMARY)
