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Vskills Certified MAG or CO2 Welding Operator Table of Content

Table of Content


CO2 welding equipment and process

  • Difference between shielded mental arc welding and CO2 welding
  • The principal of CO2 welding

CO2 welding equipment and accessories

  • Curve A
  • Touch assembly
  • Curve B
  • Control system
  • Wire reel
  • Wire feel drive motor

Setting up of GMA welding machine

  • Direct current electrode positive(DCEP)
  • Direct current electrode negative (DCEN) or DCSP
  • Wire feeder and  drive unit
  • GAM/CO2 welding torch-welding gun
  • Smoke extracting torch system
  • Shutting down the plant

Advantages ,disadvantages of CO2 welding over SMAW process and application of CO2 welding

  • Advantages
  • Disadvantages
  • Application of Co2 welding process

Base metal preparation and types of metal transfer in GMAW/ Co2

  • Base metal preparation
  • Globular transfer
  • Short circuit transfer (DIP transfer)
  • Spray transfer
  • Electrode
  • Types of metal transfer
  • Welding current
  • Arc travel speed
  • Stick out
  • Arc voltage
  • Welding procedure
  • Electrode position
  • Welding position
  • Safety in GMA welding / Co2 welding

Straight line beading on MS plate in flat position

  • Preparing the metal surface
  • Welding method
  • Welding of different joints in the flat position by GMAW / Co2 welding
  • Fillet weld on a lap joint
  • Fillet welt on tee joint – flat position
  • Groove weld on a butt joint – flat position

Welding Wires used for Co2 welding in application

  • Chemical properties
  • Chemical composition, Weight percent

Wire feed system – Difficulties

  • Drive rolls and wire guide tubes

Shielding gases for GMA welding

  • Argon Carbon dioxide
  • Argon – oxygen

Laying straight line beads and welding T fillet joint in horizontal position

  • Suggested gases and gas mixture for use in GMAW short circuiting transfer

Welding joints in vertical position

  • Groove weld but joint – vertical up – uphill motion

Burn – off characteristics of filler wire in Co2 welding

  • Principle of self regulating arc length in GMAW/Co2

Flux cored arc welding

  • Metal transfer in FCAW
  • Classification of flux cored wires

GMA narrow gap welding

Weld defects, causes and remedies in Co2 welding / GMAW

  • Troubleshooting Welding condition and defects

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