MIG Welding

1
MIG Welding
2
Overview

• Welding a process of joining two materials that
  coalesce at their contacting surfaces through the
  application of heat.
• Advantage portable, permanent, stronger than
  the parent materials with a filler metal the
  most economical method of joining in terms of
  material usage and fabrication costs.
• Disadvantage expensive manual labour,
  high-energy and important safety considerations
  does not allow for disassembly, defects can be
  concealed.

3
MIG welding

• A continuously fed metal electrode (wire)
  contacts the base metal and produces heat through
  an arc of electrical current. The arc is
  shielded by an inert gas to inhibit oxidisation.

4
Typical setup for wire speed

• The wire feed rate or speed is set using the dial
  on the wire controller.
• This setting increases or decreases the
  current or heat. This setting is measured in
  amps.
• Ideal settings can be fixed and monitored by the
  amp meter on the front panel of the welder.
• Ideal settings can be found in the wire
  manufacturers data book, related to the
  appropriate current.

5
Types of joint

• Butt joint
• http//www.youtube.com/watch?vXYBjLvxG5z0
• Corner joint
• http//www.youtube.com/watch?vsNSHDork_Yw
• Lap joint
• http//www.youtube.com/watch?vJqFp5kCeTA0
• T joint
• http//www.youtube.com/watch?vNNz_Bbo4Ojg

6
Technique

• Speed of movement is very important.
• The angle and direction for a right-handed
  person.
• (Left-handed people move to the right, angled to
  the left.)

7
Method of welding

• The following films will show you how to use a
  MIG welder. Watch and listen very carefully,
  taking notes, to remember all the tips that are
  given in each clip. Remember, the best way to
  learn how to weld is practise, practise and
  practise some more.
• http//www.youtube.com/watch?vZNyAzVQTY6Yfeature
  related
• http//www.youtube.com/watch?vlzBGZaS1apwfeature
  related
• http//www.youtube.com/watch?vNCrJWoid9-Yfeature
  related