WeldingWelding

TransportationTransportation

Mr. O’RourkeMr. O’Rourke

What is Welding?What is Welding?

A fabrication process that joins A fabrication process that joins metal. This is done by melting the metal. This is done by melting the work pieces and adding a filler work pieces and adding a filler material to form a pool of molten material to form a pool of molten material that cools to become a material that cools to become a strong joint. strong joint.

How Does it Work?How Does it Work?

Welding uses an energy source (gas Welding uses an energy source (gas flame, electric arc, or laser) to heat flame, electric arc, or laser) to heat and melt metals together. This and melt metals together. This meting causes impurities in the meting causes impurities in the metal which are shielded by various metal which are shielded by various gases to provide a clean weld.gases to provide a clean weld.

Types of WeldingTypes of Welding

Gas Metal Arc Welding (metal inert Gas Metal Arc Welding (metal inert gas or MIG)-gas or MIG)-is a semi-automatic process is a semi-automatic process that uses a continuous wire feed as an that uses a continuous wire feed as an electrode and an inert or semi-inert gas electrode and an inert or semi-inert gas mixture to protect the weld from mixture to protect the weld from contaminationcontamination. .

MIG Welder ComponentsMIG Welder Components

Power SwitchPower Switch Voltage AdjustmentVoltage Adjustment Wire Speed AdjustmentWire Speed Adjustment TorchTorch GroundGround Wire SpoolWire Spool Gas tankGas tank

How Do We MIG Weld?How Do We MIG Weld?

Clean weld surfaceClean weld surface Ground out work pieceGround out work piece Set voltage and wire speedSet voltage and wire speed Squeeze trigger keeping torch tip Squeeze trigger keeping torch tip

1/4-1/2” from work piece1/4-1/2” from work piece Move torch tip in small circular, U Move torch tip in small circular, U

shaped, or zig-zag motion shaped, or zig-zag motion

MIG Weld ProblemsMIG Weld Problems

Things to consider: Torch distance, Things to consider: Torch distance, travel speed, voltage setting, wire travel speed, voltage setting, wire speed setting, torch motionspeed setting, torch motion

SafetySafety

Safety GlassesSafety Glasses Welding MaskWelding Mask GlovesGloves Long sleeves, pantsLong sleeves, pants No open toe shoesNo open toe shoes VentilationVentilation

Bright Light!!!- High Heat!!!Bright Light!!!- High Heat!!! Yell Cover Before Beginning Your Weld!Yell Cover Before Beginning Your Weld!

Benefits of MIG WeldingBenefits of MIG Welding

Can be use on carbon steel, stainless Can be use on carbon steel, stainless steel, aluminum, copper, nickel, steel, aluminum, copper, nickel, bronze and morebronze and more

All position capabilitiesAll position capabilities Fairly easy to learnFairly easy to learn

Disadvantages of MIGDisadvantages of MIG

Only for thin to medium thicknessesOnly for thin to medium thicknesses Less portable than other forms due Less portable than other forms due

need for gas tankneed for gas tank Sloppier than other formsSloppier than other forms

Other Forms of WeldingOther Forms of Welding

Gas tungsten arc weldingGas tungsten arc welding (tungsten Inert Gas, TIG)(tungsten Inert Gas, TIG)

Shielded metal arc weldingShielded metal arc welding (stick, arc)(stick, arc)

Oxygen-acetyleneOxygen-acetylene