Hot Approaches For Welding Strip Steel

Hot Approaches For Welding Strip Steel

Consistently Stronger Welds.
In 2003, ten comparable test coupons of welded SCS processed steel and HRPO sheets were tested to failure at an accredited testing lab. It required 580 pounds greater shear load to cause failure in welded SCS samples than the Hot rolled pickled and oiled samples .

The SCS sheet steel edge originates from higher weld integrity. A certain level of the weld arc’s energy goes toward heating the oil on P&O sheets. This presents even additional contaminants to a Oiled strip steel surface that is already relatively dirty in comparison to SCS sheet steel. The net consequence is to lower the integrity of Oiled strip steel welds compared to SCS processed steel welds.

Most sheet metal fabricators who turned to SCS treated steel documented cleaner, stronger welds with an expected amount of spatter. Nevertheless, a few claimed undesirable concentrations of spatter.

To discover the root cause, The Material Works recruited the assistance of the State of Illinois Manufacturing Extension Center which provides specialized services to companies. IMEC’s project manager teamed up with a specialized welding consultant to perform controlled welding tests of SCS treated steel. First, they replicated the welding methods of fabricators who claimed excessive spatter and saw similarly undesirable results.

Then they, analyzed adjustments in shielding gas make up and filler wire feed rate. Switching from 90%Argon-10%CO2 to 95%Argon-5%Oxygen increased arc stability and significantly reduced spatter. Lowering wire feed speed functioned effectively with the different shielding gas formula. Using ER70S-6 filler wire at a slower feed speed with the Argon-Oxygen blend provided notably better penetration and enhanced bead physical appearance when welding at the same speed.

The research discovered that the most effective parameters for welding SCS strip steel (or Oiled strip steel for that matter) were different from what these fabricators had been using. A switch to the optimized shielding gas/filler wire pairing not only assures outstanding SCS sheet steel welding performance, it also delivers savings on consumables!

The gas supplier for the analysis sells the new Argon-Oxygen mix at 5% lower than the Argon-CO2 mix. But larger savings are possible on filler wire. The more consistent weld bead you get with optimized SCS sheet steel parameters means a reduced amount of filler material for a given weld joint. Couple that with a lower wire feed rate for the identical welding rate, and the savings in welding wire can achieve 30%.