Spot Welding Galvanized Sheet Metal

Weld time and or weld power need to be increased to spot weld galvanized steel.

Spot welding galvanized sheet metal.

Welding of the galvanized steel is done similar to the welding of bare metal with a difference of low vaporization temperature in the metals with zinc coating. Spot welding galvanized steel causes very little spatter. Electrode force is usually increased by 10 to 20 compared to the equivalent setting for uncoated steel of a given thickness otherwise a poorer process tolerance narrower welding range is likely. A one step scheme with no pre heating stage and a two step scheme comprising a pre heating stage followed by a main welding stage.

Don t attempt to weld thin materials like sheet metal with flux cored wires which put more heat into the base metal. Tig welding sheet metal. When mig welding galvanized steel the weld puddle is 2550 degrees f. Hold the grinder at a 15 degree angle to the metal and make long passes along the weld area with light pressure being applied to the grinder.

This portable air cooled spot welder makes quick strong spot welds without having to install a 240 volt outlet. Welding galvanized steel is an important and valuable technique in the metal fabrication process especially when producing galvanized steel wire cloth or galvanized steel gratings but people are shying away from it lately due to the toxic fumes that welding galvanized steel produces. Welding of steel is done at 2550 degrees f. Welds uncoated mild galvanized or stainless sheet steel to 1 8 in.

To weld a tear or split in galvanized steel start on any edge of the metal. Forget the larger 1 8 inch tungsten electrode and use a smaller one. Combined thickness mild steel two pieces of 20 gauge galvanized. The invention is further directed to a method of effecting spot welds between galvanized sheets which includes the step of interposing between a conductive carrier electrode and the metal surface a.

The spot welder has 6 in. Tongs lock firmly onto materials. Work slowly around the exterior edge on the metal itself moving forward 2 3 inches 5 1 7 6 cm before bringing your welding rod back over the surface you just covered. To weld sheet metal with solid wires use electrode positive ep or reverse polarity.

Removing galvanizing from galvanized steel is best accomplished with a hard wheel flapper wheel or grinding disc attached to a grinder. This study investigated the resistance spot welding rsw parameters for an uncoated mild steel sample and two hot dip galvanized steel samples with different zinc layer thicknesses. It should be obvious even to the causal observer that if you put 2550 degree liquid steel over a galvanized coating that boils at 1350 degrees f. That a great deal of spatter will occur.