Submerged Arc Welding

  • Uses bare wire electrode.
  • Fed automatically from spool.
  • Generates electric arc to heat metal/
  • Flux in powder form.
  • Fed using a hopper.
  • Electric arc melts joint, flux and electrode.
  • Excess flux is collected and re-used.
  • Fully automated process.
  • Used on Low carbon steels.
  • E.g. Ship building and bridge construction.

Resistance Spot welding

  • Components to be joined are placed between two non consumable electrodes and pressed together.
  • The current is passed through the electrodes which generates the required heat.
  • A nugget weld (circular mark) is formed.
  • It is used on sheet metals.
  • The process is energy efficient and does not require a filler metal.

Resistance Seam welding

  • Uses copper rollers to provide a continuous run of overlapping spot welds.
  • The current is set at intervals and is generated by a resistance to the flow of an electric current through the parent metals.
  • The heat generated depends on time, resistance and current.