Dear Readers,
The American Welding Society’s classification number series for welding electrodes has been adopted by the welding industry. AWS CLASSIFICATION A 5.1 & 5.5 for Covered Carbon Steel & Low alloy steel welding electrodes. The electrode identification system for steel arc welding is set up as follows:
E
|
7
|
0
|
1
|
8
| X |
1. Prefix Letter 'E' stands electrode for arc welding.
2. The first two digits indicate tensile strength (the resistance of the material to forces trying to pull it apart) in thousands of pounds per square inch of the deposited metal.
3. The third digit indicates the position of the weld.
1 is for all positions;
2 is for flat and horizontal positions only;
3 is for flat position only.
4. The fourth digit indicates the type of electrode coating and the type of power supply used;
0. High cellulose sodium DC reverse polarity (+)
1. High cellulose potassium AC or DC reverse polarity (+)
2. High titania sodium AC or DC straight polarity (-)
3. High titania potassium AC or DC either polarity ( ± )
4. Iron powder titania AC or DC either polarity ( ± )
5. Low Hydrogen sodium DC reverse polarity (+)
6. Low Hydrogen potassium AC or DC reverse polarity (+)
7. High iron oxide, iron powder AC /DC (+) / DC (-)
8. Low Hydrogen potassium ,iron powder AC/DC (+)
5. Suffix
Letter 'X' stands for suffixes A1,B1,B2,B3,C1,C2,C3,D1,D2,G,M etc. and
designates the chemical composition of the deposited weld metal.
Example illustrated in below picture. Click on Picture to enlarge
Example illustrated in below picture. Click on Picture to enlarge
The number E7018 indicates an arc welding electrode with a minimum stress relieved tensile strength of 70,000 psi; is used in all positions; and Low Hydrogen potassium ,iron powder with AC/DC (+) polarity is required.
