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

25. Welding Positions
Vertical
Horizontal

26. Welding Positions
Flat
Overhead