Answer:
Factors for Selecting the Right Stick Electrode
Stick welding takes practice to master and selecting the correct electrode for the job can be equally challenging.
Welding rod selection
Stick electrodes are available in a wide range of types, each of which provides different mechanical properties and operates with a specific type of welding power source.
Base metal properties
The first step in choosing an electrode is to determine your base metal composition. Your goal is to match (or closely match) the electrode composition to the base metal type, which will help ensure a strong weld.
Tensile strength
To prevent cracking or other weld discontinuities, match the minimum tensile strength of the electrode to the tensile strength of the base metal. You can identify a stick electrode’s tensile strength by referring to the first two digits of the AWS classification printed on the side of the electrode.
Base metal thickness, shape, and joint fit-up
Thick materials require an electrode with maximum ductility and low hydrogen to prevent weld cracking. Electrodes with AWS classification numbers ending in 15, 16, or 18 provide excellent low–hydrogen properties and good toughness (high impact values) to accommodate for residual stress.
Welding position
To determine what position(s) a particular electrode is qualified for, refer to the third digit in AWS classification. Here’s how you decipher the qualified electrodeposition:
- 1 = flat, horizontal, vertical, and overhead
- 2 = flat and horizontal only
For example, a 7018 electrode can be used in flat, horizontal, vertical, and overhead positions.
Specification and service conditions
Make sure to assess the conditions that the welded part will encounter throughout its service. If it will be used in high heat or low-temperature environments subjected to repetitive shock loading, a low hydrogen electrode with higher ductility will reduce the chance of weld cracking. Also, be certain to check for welding specifications if you’re working on critical applications such as pressure vessel or boiler fabrication. In most cases, these welding specifications will require you to use specific types of electrodes.
Environmental job conditions
To achieve the best result, you should always remove excessive mill scale, rust, moisture, paint, and grease. Clean base metals help prevent porosity and increase travel speeds. If cleaning your base metal is not possible, E6010 or E6011 electrodes deliver a deeply penetrating arc that has the ability to cut through contaminants.
Choosing welding rods
Consideration of the above factors will help you overcome the challenges of selecting the correct electrode for your particular application. However, given the wide range of available electrodes, several solutions may exist for one application.
Hope this helps good luck and stay safe always <3
