If you are in a construction and manufacturing industry, you must be aware of the importance of welding electrodes. An electrode is a coated metal wire with a similar composition to the metal being welded. There are different types of welding electrodes available online. Let’s discuss a few factors that need to be kept in mind while choosing the right welding electrode.
How to Choose Welding Electrode?
Though selecting the right electrode is determined by the requirements of the welding job. However, these are a few factors that you can consider while buying a quality welding electrode.
- Tensile strength
- Corrosion resistance
- Base metal
- Weld position
Different Types of Electrodes
Welding electrodes are mainly classified into two types
These electrodes are low melting point electrodes. When an electrode is struck, the arc starts to melt the end of the electrode. A molten electrode is transformed in the form of metal droplets.
Main Features of Consumable electrodes
- These are thermally efficient than non-consumable electrodes.
- They are made of different materials depending on the need and chemical composition of metals to be joined.
- These are used in MIG welding in the form of a bare electrode.
- The most common core material is mild steel, low alloy steel, and nickel steel.
Consumable electrodes can be classified in different groups; bare electrode, lightly coated electrodes, heavy coated electrodes.
As the name suggests, these are uncoated electrodes used in submerged arc automatic welding. Bare electrodes are made of wire composition required for specific applications. These electrodes don’t have a coating. Mostly manganese steel is welded by using a bare electrode, where a coated electrode is not required.
Light Coated Electrodes
These electrodes have a definite composition. A light coating is applied on a surface by washing, dipping, brushing, spraying, tumbling or wiping. The coating improves the properties of the arc stream.
The coating generally serves the functions mentioned below-
- It reduces impurities like oxides, sulfur, and phosphorus.
- It changes the surface tension of the molten metal so that globules of metal are smaller and frequent. This makes the flow of molten metal more uniform.
- It increases the arc stability by introducing readily ionized into the arc stream.
- Some of the light coatings may produce a slag. The slag is thin and does not act similarly as the shielded arc electrode type sag.
Heavy Coated Electrodes
Heavy coated electrodes have a definite composition on which a coating is applied by dipping or extrusion. The electrodes are manufactured in three types: with cellulose coating, mineral coating, and a combination of minerals and cellulose. The cellulose coating is composed of soluble cotton or other forms of cellulose with small amounts of potassium, sodium or titanium. The mineral coating is made of sodium silicate, metallic oxides clay, and other inorganic substances. Cellulose-coated electrodes protect the molten metal with a gaseous zone. These electrodes are mainly used for welding steel, cast iron, and hard surfacing.
These electrodes do not melt or get consumed during the welding process. These electrodes involve the use of high melting point materials.
Main Features of Non-Consumable Electrodes
- While welding with these electrodes, a filler metal is needed to fill up the gap between the two parts.
- These are used in carbon arc welding Tungsten Inert Gas (TIG) welding.
- Carbon or graphite electrodes are cheaper than tungsten electrodes.
Tungsten electrodes are also known as non-consumables electrodes. These are of three types: pure tungsten, tungsten coating with 1 or 2 percent thorium, and tungsten containing 0.3 – 0.5 percent zirconium.
Pure Tungsten Electrode- These are generally used in less critical welding operations than the tungsten which is alloyed. This type of electrode has low current carrying capacity and low resistance to contamination.
Thoriated Tungsten Electrodes- These electrodes are superior to pure tungsten electrodes. They have higher electron output, better arc stability, high current-carrying capacity, longer life, and greater resistance to contamination.
If you are a professional welder, you must be aware of the different types of electrodes and their applications. If you are looking for a welding electrode online, browse through our website moglix.com and get the best assortment of brands like Ador, Arcon, D&H, ESAB, JMV and many more at the best price.