Hard Facing with a mig

Hardfacing is practical if part life is increased substantially, and down time and/or labor savings in regard to part replacement can be realized.

Another consideration is the overall comparison of increased part life a given welding process can deliver. In other words, what process will yield the most substantial increase in part life?

When comparing arc welding processes, the wire fed machine will deliver superior deposit efficieny on average, and it may deliver better time savings in regard to actual weld time. (Some of the new high deposition SMAW electrodes will compete vigorously with the wire welders in deposition rates if the wire welder is in the short circuit mode.) Another consideration is the base metal composition. If interpass temps must be controlled, then actual welding time may not be much of a factor by comparison.

There is another process available today which brings yet another set of considerations to the table. These puddle torches and powders we have today, deliver an average of 4 times additional life to a wear part. (I have personally seen increases as high as ten times.) The basic factor here is lack of dilution of the hardface material into the substrate. The less penetration into the base material, the more pure the deposit. Another key factor which involves time spent applying the material, is the base material thickness, and required deposit thickness. For example, a puddle torch deposit is much faster and easier to apply on a thin edge, or a thin section, than an electric arc deposit. A torch applied overlay will also require far less deposit thickness(to achieve high hardness). A savings of both time and material. (Average deposit thickness is not recommended to be more than 1/32" in depth.) Overall hardness that is achieved with a torch, is by nature, superior to any arc process. To sum up, enhanced control over heat input and deposit thickness, combined with smooth deposit texture and superior deposit hardness, create a competitive process.

I have not priced hard face consumables lately but if labor was free I would think it would cost you about $5 a piece to weld depending on how much welding needs to be done. Mig would be faster in this application. Depending on how much weld needs applied as to the wire spool size to the cost of the wire spool. Do you need it next year? Then a 50lb spool might cost more but cheaper in the long run. If welding flat look at .045 wire or 3/16" electrodes if you have enough machine.

On hardface electrodes be sure and look at what base metal prep needs to be done. Some electrodes require a prebase metal weld cover before a hard surface can be applied.

T_Bone