SMAW ELECTRODE CLASSIFICATIONS
SMAW (stick) electrodes follow a numbering system that tells you the specification and properties of the consumable and it helps you select the right electrode for your welding material and application. The most common two classification systems are the AWS and EN ISO designation standards. Below is an example showing the AWS and EN ISO designation system for carbon steel electrodes and non-ally & fine grain electrodes respectively. For detailed information on electrode classification refer to the respective AWS and EN ISO standards.
AWS A5.1 designation of electrode (Example)
Below is an example for Kiswel's K-7018HR low hydrogen electrode with AWS A5.1-2012 classification.
K-7018HR: E 7018-1 H4R
E - Type of welding consumable ie. electrode
70 - Code for the min. tensile strength in ksi. (In this case 420 MPa)
1 - Code for the welding positions (1 = All positions)
8 - Type of coating, current and polarity (In this case iron powder low hydrogen. Polarity AC or DCEP)
-1 - Electrode meets low temperature impact requirements
H4 - Code for diffusable hydrogen. (In this case < 4 mg / 100 g weld metal)
R - Code for reduced moisture content
Below table specifies the types of electrode coating with corresponding welding polarity.
* DCEP: Direct current electrode positive (reverse polarity)
* DCEN: Direct current electrode negative (straight polarity)
ISO 2560-A designation of electrodes (Example)
The European standard for covered electrode classification has to systems they use to classify covered electrodes as below:
1. Suffix letter "A": System based on the yield strength and the average impact energy of 47J of the all-weld metal
2. Suffix letter "B": System based on the tensile strength and the average impact energy of 27J of the all-weld metal
Below is an example for Kiswel's K-7018HR low hydrogen electrode with EN ISO 2560-A:2006 classification.