Welding rods come in a variety of sizes and materials, each of which has a unique marking system. This marking system includes a weld rod type, a symbol and a rod number (or grade). Different weld rod manufacturers adhere to differentiating symbols, meaning the same weld rod type could have different symbols and grade numbers depending on the manufacturer. This article provides a comprehensive guide to explain common weld rod types, symbols, and numbers.
Weld rod types refer to the composition of the rod, as well as its shape and size. All rods are organized and named according to the American Welding Society specification standard. Specific types of welding rods include:
• Electrodes: These are coated rods used in arc welding. The shielding from the coating helps protect the weld pool from contaminants.
• Flux-Coated Rods: These rods are similar to electrodes but come with a flux coating to help protect and shape the weld pool.
• Solid Rods: As the name suggests, these use bare solid wire with or without fluxes or gas shield.
• Flux Cored Arc Welding (FCAW): This is a combination of solid and flux-coated wire.
• Babbitted Rods: These rods can be made of wrought iron, bronze, gold or silver and are used to pour molten metal into molds.
• Oxyacetylene Rods: These are specially designed rods used for oxyacetylene welding and brazing.
The symbols used on welding rods identify the classification of the specific weld rod. This classification indicates not only the type of rod (acid, basic, or flux-cored), but also its material composition, filler metal specifications, position of the weld and current requirements (AC/DC). Common symbols include A, E, and F, with each of these designations referring to specific types of rod:
• Arc Welding Electrodes: These rods are marked with an “E” followed by a two or four digit number (e.g. E6010). The number following the E indicates the strength of the weld, with lower numbers representing the lowest strength weld rod available. Welding professionals will use the lower numbers for out-of-position welding or in applications where the joint stability is a concern.
• Flux-Cored Arc Welding (FCAW) Electrodes: The letters “F” or “FCAW” is used to designate these rods. The last two digits provide information about chemical makeup, type of flux-cored electrode, and strength of weld (lower numbers representing the lowest strength rods).
• Gas Metal Arc Welding (GMAW) Electrodes: Gas metal arc welding electrodes are known as metal-cored wires. They are designated by “M” followed by a two or four digit number. The numbers provide information about chemical makeup, type of metal-cored electrode, and strength of weld.
Finally, weld rods are also assigned numbers (or grades). These grades refer to the strength and usability of the weld rod. The higher number weld rod will have a higher quality and strength rating. The grade numbers also provide information about chemical makeup, type of metal-cored electrode and strength of weld.
The weld rod types, symbols and numbers discussed in this article should be used as a general guideline only. For definitive information regarding the weld rod type, symbol and number, consult the manufacturer or the American Welding Societys welding rod specification standard.
