Impax IM-MIG150 Instruction Manual page 10

SAFETY INFORMATION
Both wire and shielding gas composition are
essential variables in MIG/MAG welding and will,
therefore, influence the process performance.
Note: Tubular / Flux Cored wire produces its
own shielding gas and does not require the use
of external shielding gas
Key Characteristics:
Wires are available in a wide range of
compositions to suit different metallic materials,
e.g. steels, stainless steels, aluminium alloys,
nickel alloys, titanium alloys
MIG/MAG wires are normally specified by
composition.
Wires are typically supplied with diameters in
the range 0.8mm to 2.4mm
Wires are normally available on 15kg reels,
The wire is often layer wound to ensure smooth
feeding
The flux core produces its own shielding gas
and does not require the use of external
shielding gas
Wire Composition
Selection of the appropriate composition of the
wire electrode can be a difficult task
The selection of consumables should be
confirmed by welding trials
The main sources of information are:
• Electrode manufacturer's handbook
• Electrode manufacturer's technical department
• Parent material manufacturer
• Previous experience.
Carbon and Low Alloy Steels
AWS A5.20: Specification for carbon steel
electrodes for flux cored arc welding.
AWS A5.29: Specification for low alloy steel
electrodes for flux cored arc welding.
Stainless Steels
AWS A5.22: Specification for stainless steel
electrodes for flux cored arc welding and
stainless steel flux cored rods for gas tungsten
arc welding.
Aluminium Alloys
The main concerns when welding aluminium
alloys are the risk of solidification cracking and
porosity. Wires for
AWS A5.10/A5.10M: Specification for bare
aluminium and aluminium alloys welding
electrodes and rods.
Wire Diameter
Selection of the appropriate wire diameter is
dependent on a number of factors, chiefly:
• Mode of metal transfer
• Welding current
• Deposition rate
The electrode manufacturer usually specifies the
typical current ranges of operation for a
particular wire size. It is then a case of ensuring
that the welding current is in the mid-upper
range of current-carrying capability.
Storage of Wires
It is essential that all consumable wires are in
first-class condition. This is particularly so for
MIG/MAG welding where process stability relies
on consistency of wire feed and electrical
contact. In order that this can be achieved and
maintained, the following control measures may
be necessary -
The wire should be in a clean condition with the
minimum of grease and drawn-in dirt. Therefore,
when not in use, reels should be stored
correctly and not left on equipment for long
periods. Dust covers should be used, if
available.
If a wire has been left on the equipment for a
short period of time, it is good practice to run
off at least one layer of wire to remove the worst
of any surface oxidation or contamination that
may have occurred.
For storage, consideration should be given to
factors such as humidity, temperature and.
Reels should be stored at a temperature above
the dew point of the local area.
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