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VIPER MIG 135
OPERATING MANUAL
13. Drive Roller Selection
The importance of smooth, consistent wire feeding during MIG welding cannot be emphasised enough. The smoother
the wire feed, the better the welding will be. Feed rollers or drive rollers are used to feed the wire mechanically along the
length of the welding gun.
Feed rollers are designed to be used for certain types of welding wire, and they have different types of grooves machined
in them to accommodate the different types of wire. The wire is held in the groove by the top roller of the wire drive unit
and is referred to as the pressure roller. Pressure is applied by a tension arm that can be adjusted to increase or decrease
the pressure as required. The type of wire will determine how much pressure can be applied and what type of drive roller
is best suited to obtain optimum wire feed.
13.1 Solid Hard Wire (V Groove)
Steel or stainless steel require a drive roller with a V shape groove for optimum grip and drive capability. Solid wires can
have more tension applied to the wire from the top pressure roller that holds the wire in the groove, and the V shape
groove is more suited for this. Solid wires are more forgiving to feed due to their higher cross-sectional column strength.
They are stiffer and don’t bend so easily.
13.2 Flux Cored / Gasless Wire (Knurled/F Groove)
These wires are made up of a thin metal sheath that has fluxing, and metal compounds layered onto it and then rolled
into a cylinder to form the finished wire. The wire cannot take too much pressure from the top roller as it can be crushed
and deformed if too much pressure is applied. A Knurled/F groove drive roller has been developed, and it has small
serrations in the groove. The serrations grip the wire and assist in driving it without too much pressure from the top roller.
The downside to the knurled wire feed roller on flux-cored wire is it will slowly eat away at the surface of the welding wire,
and these small pieces will eventually go down into the liner. This will cause clogging in the liner and added friction that
will lead to welding wire feed problems. A U groove wire can also be used for flux cored wire without the wire particles
coming off the wire surface. However, it is considered that the Knurled roller will give a more positive feed of flux cored
wire without any deformation of the wire shape.
V GROOVE
F(Knurled) GROOVE
13.3 VIPER 135 SYNERGIC Rollers
13.3.1 V Groove Roller (Steel Wire)
SKU
Description
XA-DRV60608
VIPER 135 ROLLER - 25 x 7.35 x 7 - 0.6/0.8
V GROOVE
13.3.2 Knurled/F Groove (Flux-Cored Wire)
SKU
Description
XA-DRK60809
VIPER 135 ROLLER - 25 x 7.35 x 7 - 0.8/0.9
F GROOVE
25mm
7.35mm
7mm
