Welding techniques: Shielded Metal Arc Welding (SMAW)
Today we are launching our new monthly column dedicated to welding. It will tell you all you need to know regarding the main accessories, materials and techniques in order to choose the best engine driven welder for your needs. Let’s start with the best known: Shielded Metal Arc Welding (SMAW).
Shielded Metal Arc Welding: what is it?
It is the most common, fastest and cheapest method of welding.
It uses an electrode that is coated with specific materials, which prevents the weld from oxidizing and allows it to stabilize the current arc.
Let’s start with the basics: To begin with, an electrode holder and the material that needs to be welded is connected to the polarities of the welder. The electrode is then attached to the clamp, and when it is brought into contact with the material that needs to be welded, a current arc is produced. In this way, the material that needs to be welded, the coating of the material and the electrode core fuse together.
The different types of electrodes and their electrode coating types:
Acidic (silica, iron silicate): cheap, provides good arc stability.
Cellulosic (cellulose, silicon, manganese): excellent penetration capacity in the material. Suitable for precision work with little slag in the bath.
Rutile (rutile): cheap and easy to store, very smooth welds.
Basic (calcium and magnesium): high purification capacity of the base material, suitable for objects that need to be welded with a greater thickness.
What materials can be arc-welded with a coated electrode?
Almost all materials may be arc-welded, with the exception of lead, zinc, tin, oxygen-reactive and refractory materials.
This process is very versatile but is not recommended for welding joints thicker than 40mm. But we’ll talk about that next time.
In the meantime, follow us on our social to stay updated and find out more in the Engine Driven Welders section, or write to us for a tailor-made consultation.