(b) Multi-pass electrodes are suitable for single-pass or multipass welding; single-pass electrodes are suitable for single-pass welding only
(c) dcep, direct-current electrode positive; dcen, direct-current electrode negative
(d) t-5 electrodes are classified using dcep; however, they are sometimes used with dcen in practice
CLASSIFICATION SYSTEM FOR CARBON STEEL FLUX-CORED ELECTRODES
Low-alloy steel electrodes are classified under AWS A5.29, “Specification for Low Alloy Steel Electrodes for Flux Cored Arc Welding.” This specification uses a classification system very similar to that used in specification AWS A5.20, except that a chemical composition designator is added to the designation. An electrode classified according to this specification will have the form EXXTX-X. All of the positions before the dash have the same meaning as those in specification AWS A5.20. The position behind the dash is the chemical composition designator, which consists of a letter and a number. The letter denotes the alloy type of the electrode as follows:
Stainless steel electrodes are classified under AWS A5.22, “Specification for Flux Cored Corrosion Resisting Chromium and Chromium-Nickel Steel Electrodes.”
- Classifications to this specification have the form EXXXT-X.
- The first three positions are the chemical composition designator, which corresponds to the American Iron and Steel Institute (AISI) designations (such as 308, 316, and 410) of steels having a similar composition.
- The final position is the shielding type designator. T-1 types are designed for use with CO2 or Ar-CO2 shielding gases (classification requires the use of CO2).
- T-2 types are designed for use with Ar-2O2 shielding gas. T-3 types are self-shielded. A T-G type is included for electrodes that are not covered by the other shielding-type designators.
Nickel-Base Electrodes: A specification for nickel-base flux-cored electrodes has not yet been published. The manufacturers of these electrodes should be consulted for information on their usability, composition, and properties.