ME 353 Presentation 11-3-2000 Presented by Damon Ogden
• • • • • • What is Arc Welding The four most common types Non destructive testing Design considerations Strength Safety Feel free to ask questions at any questions at any time.
• Welcome to the world of WELDING
What is Arc Welding?
An electric arc between the and electrode and the work piece generates heat. Sufficient heat is generated to melt the work pieces together.
ELECTRODE ARC WORK PIECES
The range of welding current used can be from 5 to 500 amps. The voltage ranges from 20 to 30 volts, AC or DC. Both are determined by the material thickness. A 60 watt light bulb draws .5 amps.
Four Common Types of Welding
•Stick SMAW (shielded metal arc welding) •Mig GMAW (Gas Metal Arc Welding) •Flux-Core FCAW (Flux-core Arc Welding) •Tig GTAW (Gas Tungsten Arc Welding)
Each welding process has unique traits that make it more suited for particular processes
Electrode This is where the current passes from the welder to the work piece. There are two types: 1) Contact/consumable 2) Non Contact
Atmospheric protection There are 2 types: 1) Shielding Gas 2) Flux
Stick Weld Schematic
• Uses a consumable electrode (rod), with a flux coating. • Stick welding requires a moderate to high skill level. • Advantages: Portable Can be used in all environments Not as dependent on surface preparation
Stick welder joins sections of oil pipe in Alaska.
MIG WELDING SCHEMATIC
• The electrode is a wire, fed from a spool to the end of the “gun”. • A shielding gas is used to give atmospheric protection. • This process requires a low to moderate skill level. Advantages: 1) Very fast process 2) Easy to learn Disadvantages: 1) Weld area must be protected from air movements
Flux Core Schematic
• This process is a