Shielding and cooling a continuous weld between steel sheets/plates using a non-oxidizing atmosphere to reduce the formation of oxide on a surface of the continuous weld

A system for welding steel sheet or plate continuously, wherein the system comprises:

• a welding head configured to form a weld on one or more steel sheets or plates via relative movement between the one or more steel sheets or plates and the welding head;
• and
• a header having a hollow body extending away from the welding head in the direction of welding, wherein the body defines a plurality of openings oriented towards the weld, the plurality of openings being oriented along a single axis extending in the direction of welding through each opening of the plurality of openings and corresponding to an electrode of the welding head, wherein the plurality of openings are configured to direct a flow of non-oxidizing gas towards the weld to simultaneously shield the weld from atmosphere and cool the weld,
• wherein each opening of the plurality of openings defines a first diameter having a first area, wherein the header includes a tube defining a second diameter having a second area defined by the second diameter, wherein the openings together define a third area comprising the sum of the first area with respect to each opening, wherein the first diameter and the second diameter define a predetermined relationship between each other configured to promote even flow of gas through each opening of the plurality of openings, wherein the predetermined multiple is greater than or equal to 2 and less than or equal to 20.