Arc Welding Equipment 6831.26
Welding Machines AC – (alternating current) used for most agricultural arc welding jobs and has low purchase cost compared to other arc welders
Welding Machines DC (direct current) are generator operated and can be used where regular electrical power is not available
Welding Machines AC/DC – welders use a rectifier to change regular AC current to DC These welders can be used as either AC or DC
Welding Machines TIG (tungsten inert gas) welders have an electric power unit, a pressure reducing regulator, electrode holder, tungsten electrode, nozzle, cables and hoses, and a gas supply unit
TIG The two gases used are helium and argon
TIG The tungsten electrode is not consumed (burned) and there is no slag on the bead
TIG TIG is good for welding stainless steel and aluminum because it is stronger and more free of corrosion than other welders
Welding Machines MIG (metallic inert gas) welders are wire feed welders that use a consumable wire fed automatically through the torch and can be used in industries as an automatic welder
Welding Equipment Helmet, leather gloves, leather aprons, leather welding jacket, and leather boots are for protection
Welding Equipment Chipping hammer removes slag, and wire brush removes rust and dirt
Welding Equipment Clamps and vise grip clamps are used to hold metal in place for welding
Electrodes Electrodes are wire cores or rods usually covered in flux
Electrodes Size is the diameter of the metal rod not including flux
Electrodes Classification code system has a letter and four numbers such as E6011 or E6013
Electrodes E6011 is the most commonly used electrode for welding farm projects because it can be used for all purpose welding of mild steel, has deep penetration, and can be used with both AC and DC welders
Electrodes E6013 is a good general purpose electrode but only has medium penetration
Arc Welder An electric arc welder is used to weld two pieces of metal by melting and joining the edges of each using an electrode to help fill the space between them
TIG Welder TIG welders are best for welding aluminum and stainless steel
MIG Welder MIG welders are the best welder for welding very thin metals
Shade 10 A shade 10 lens in a welding helmet protects the eyes of the person welding or the person watching someone weld
Chipping Hammer A chipping hammer is used to remove the slag (crust) off a welded bead
Basic Arc Welding Procedure 6831.27
Clean Metal Metal should be cleaned before it is welded
Clean Metal A grinder is the fastest way, but a wire brush or other methods may be used to remove paint, rust, dirt, or oil
Beveled Metal more than ¼” should be beveled at a 30 degree angle and placed 1/16” to 1/8” apart before two pieces are welded together
Welding Joints Butt – two pieces of metal lying in the same plane such as end-to- end or edge-to-edge in a flat position
Welding Joints T – two pieces of metal placed together to form a T (two pieces at a 90 degree angle)
Welding Joints A fillet weld is used to fuse the two pieces permanently
Lap Two pieces of metal overlap each other
Corner Two pieces of metal make a 90 degree corner
Edge Two pieces placed parallel to one another or stacked on top of each other
Amperage Setting Welding position, metal thickness, and electrode size are used to determine amperage setting
Amperage Setting Amperage too low causes a narrow, high bead with poor penetration
Amperage Setting Amperage too high caused a flat bead with excessive spatter
Amperage Setting Correct amperage helps make a uniform bead with bead width and penetration depth equal to each other
Before Welding Before metal is welded, it should be identified, cleaned and cut to correct size (if needed)
Electrode Sticks If an electrode sticks to the metal, the electrode should be wiggled back and forth, or it should be released from the electrode holder
Electrode Size The maximum thickness of the beveled edge of metal should be the same as the diameter of the electrode used to make the weld
Electrode Size A 1/8” electrode for a 1/8” thick bevel
Adjust Amperage Spatter and flat bead are caused by amperage that is too high
Adjust Amperage A high narrow bead with poor penetration is caused by amperage that is too low
Strike and Arc Tapping or scratching methods can be used to strike an arc (starts a weld)
Arc Length Arc length should be the same as the diameter of electrode
Strong Weld Many different electrode movements or weaves are used to make a bead
Strong Weld Regardless of the movement used, the pattern should be uniform to make a strong weld
Travel Speed If the travel speed is too fast, the welded bead is narrow