How to choose the right welding rod?

Welding, a fabrication process used to fuse two or more metal parts together. This process typically is used on metals and thermoplastics. A welding rod commonly referred to as a welding electrode is what makes or breaks the success of this welding process. Welding electrodes are the medium used to fuse two metals together. These rods are available in different types and their usage depends on the purpose of the machinery. To enable seamless welding results, it is extremely important to choose the right welding electrodes at the initial stage.

There are 3 types of welding rods or welding electrodes produced by welding electrodes manufacturers across the world:

1. Covered rods

2. Tubular rods

3. Bare welding rods

But how does one select a suitable electrode from these for a welding process?

Here are a few steps to consider before you select your welding materials:

1. Know your base metal’s properties

Your base metal’s composition needs to match or at least closely match the electrode composition for the weld to become successful. Referring to an electrode and metal composition chart for this purpose can be helpful and convenient.

2. Check the tensile strength

Apart from matching the composition of base metal to the electrode, it is also important to match the minimum tensile strength of the electrode to the tensile strength of the metal. This will avoid cracking or other damage to the metal during the welding process. You can always check the tensile strength of the electrode by referring to the first two digits of the AWS classification printed on it. 

3. Check the welding current

Electrodes often come with the condition of being used only with certain power sources such as AC or DC current. Other electrodes on the other hand can be compatible with both. For medium or deeper penetration of the weld, using electrodes compatible with AC currents is advisable. Electrodes compatible with AC current also produce a soft arc and can be used to weld clean sheet metals.

4. Know the base metal’s thickness and shape

Determining the thickness of your base metal can help identify which electrode would suit the process. For example, thicker materials require electrodes with high ductility and low hydrogen. On the other hand, thinner welding materials require soft arc electrodes with smaller diameters. This will ensure shallow penetration and help avoid the burning of thinner material.

5. Determine the welding position

Basically, before choosing an electrode, you need to have a clear idea about your welding procedure. The position of your welding will influence the choice of welding electrode to be used. To find out about each electrode and the position it’s suitable for, refer to the AWS classification chart.

Apart from this, before you begin your welding procedure, make sure your base metal is absolutely clean of dust, rust, grease, and other contaminants. This is an important step to get the perfect desired weld. We hope this article helped you understand the process of welding electrode selection better. If you have more questions, do reach out to us as we’ll be happy to help you.