Arc Welding Techniques and Metal preparation

1
Arc Welding Techniques and Metal preparation
2
Objectives

• Understand Basic Welding techniques
• Understand the types of welds

3
Metal Preparation

• Free of dirt, grease, rust, paint, or other
  impurities
• Can Weaken the weld
• Clean by grinding, brushing, filing, or cutting

4
Welding Joints

• Butt, lap, tee, corner, and edge.
• Types of welds
• fillet, groove, plug, slot, and surface

5

• Tee weld is a type of fillet weld.
• The fillet weld
• has two surfaces at right angles,
• the bead is triangular in shape
• The groove weld
• A weld made in a groove between the two pieces of
  metal

6
Plug and Slot welds

• Used to join pieces that overlap.
• The welds are placed in plug or slot holes.

7
Surface Welds

• Beads deposited on a metal surface
• the purpose of building up the base metal.

8
Butt Joint
9
Single and Double V Butt Joint
10
Single Beveled Butt Joint
11
Lap Joints

12
Corner Joint
13
Edge Joint
14
Major Factors for Quality Welding

• 1. The proper amperage
• When correct, a sharp crackling sound can be
  heard.
• Too Low Humming
• Too Loud Popping

15
Major Factors for Quality Welding

• 2. the thickness of the base metal and the
  diameter of the electrode.
• 3. Arc Length
• equal to the diameter of the bare end of the
  electrode.

16
Major Factors for Quality Welding

• 4 Electrode Angle
• Hold the electrode at a 90 degree angle of the
  two plates being joined
• 5 to 15 degrees in the direction of travel.

17
Major Factors for Quality Welding

• 5. Speed of Travel
• It should produce a bead that is 1.5 to 2 times
  the diameter of the bare end of the electrode.

18
Welding Procedures

1. Make sure safety is being followed
2. Insert the electrode in the electrode holder and
   hold it about 1 inch above the metal
3. Turn Welder on

19
Welding Procedures

• Lower the helmet, bring the electrode in contact
  with the work and withdraw it slightly.
• The metal and the electrode melt forming a metal
  pool called a crater

20
Welding Procedures

• 8. There are two methods used in starting the
  arc.
• striking like a match.
• tapping the electrode quickly on the surface to
  prevent it from sticking

21
Welding Procedures

• 9. Raise the tip of the electrode to about 3 /16
  inch above the base metal. This forms a long arc
  which is held for a three count in order to
  preheat the base metal.
• 10. Lower the electrode to the correct arc length.

22
(No Transcript)
23
(No Transcript)
24
(No Transcript)
25
Welding Positions

• Vertical
• Horizontal

26
Welding Positions

• Flat
• Overhead