Transcript Welding - Images

Welding
Objective: learn to safely use an arc welder
by following safety precautions, knowing how
to use equipment and tools, and having an
overall general knowledge of welding
Types of Arc Welders
 AC (Alternating Current)- low voltage
welder that places a limit on types of
electrodes used.
 DC (Direct Current)- has more advantages
and a wider variety. It can be used with no
power source. (Gasoline Engine)
 AC/DC- (not back in black)- but a
combination welder that gives you all of
the advantages of arc welders.
Equipment and Tools
 1. Ground Clamp- clamps to the metal
being welded or to the metal table.
 2. Electrode Holder- holds the electrode
(rod) to be used while welding.
Equipment and Tools
 3. Head Shield (Welding Helmet)consists of a #10 lens that protects the
face and eyes from UV rays and spatter.
 4. Leather Welding Gloves- Protects
hands from rays and spatter.
Equipment and Tools
 5. Leather Apron- protects clothing from
rays and spatter.
 6. Wire brush and Chipping Hammercleans excess slag and chips the slag.
Equipment and Tools
 7. Tongs and Pliers- used to carry hot
metal.
 8. Welding Table- used when welding
small projects.
Two Types of Electrodes
 1. Bare or Lightly Coated- usually used by
beginners, and has little or no flux.
 2. Shielded Arc or Heavy Coated- has a
flux coating that usually forms slag on the
bead to produce a stronger weld.
Sizes of Electrodes
 Sizes will range from 1/16” – 3/16”
 We normally use 1/8”.
Identifications of Electrodes
 1. By a four-digit number.
 2. By the color of the flux.
 Example: 6013
 60- tensile strength (thousand lbs./square
inch)
 1- Welding position
 3- Special Characteristics
How Do I Know What Kind of
Electrode I Need?
 1. Kind of metal to be welded.
 2. Kind of weld and type of joint being
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welded.
3. Type of welding machine being used.
4. Position of the weld.
5. Thickness of the metal being welded.
6. Required strength of the welding joint.
7. Speed of travel.
Striking An Arc
 Methods:
 1. Scratching Method- used by beginners,
move the electrode across the metal at an
angle, as if you’re striking a match.
 2. Tapping Method- Move downward in a
vertical motion. As soon as the electrode
touches the metal withdraw to maintain the
correct arc length.
Freezing Effect
 Sometimes when welding, the electrode
will stick to the metal. Don’t panic!!!
Simply move the electrode back and forth
to release. If this doesn’t work unclamp
the electrode from the electrode holder
and turn the machine off.
Running the Bead
 Strike the arc and form a puddle. Maintain
the width of the puddle throughout the
bead