Welding is a process that is at once exceptionally advanced in its more modern forms but dates back as far as the bronze age and the early days of metalworking in its earliest forms.
It was initially developed as a way to make the most of iron in 12th century BC Damascus by laying together soft and tough iron with high carbon material, before hammer forging the two together to create a tough steel blade.
However, in modern construction, there are many different types of welding and a welder hire can take many different forms, from the arc welding process to gas and resistance welding, depending on the type of task that is being undertaken.
Here are some of the most common types of welding, what equipment is used and where you are most likely to see it.
- Arc Welding
The most common modern welding process and the one that comes to mind when people think of welding, arc welding is where two pieces of metal are bound together by using electricity to generate huge amounts of heat.
The electrical discharge, or electric arc, often creates a huge amount of lights and sparks, due to the intense temperatures that are creating, which melt the two pieces of metal together, creating a strong joint once they cool.
Often this involves the use of a filler metal, often described as an electrode material or simply as a “stick”, which acts as the glue to piece different pieces of metal together.
In its most common form, shielded metal arc welding, the electrode’s flux coating gives off vapours that work as a shielding gas and create a slag layer to protect the area from contamination and corrosion.
There are several different forms of arc welding, which serve to increase productivity, reduce the risk of contamination or reduce the need for a consumable electrode layer.
Gas arc welding uses an inert or semi-inert gas mixture that reduces contamination further and speeds up the process, whilst flux-cored welding uses a powder fill material that is even faster and can penetrate further into metal.
As well as this, there is tungsten arc welding, which uses a non-consumable electrode to create highly accurate welds of thinner metals.
- Plasma Arc Welding
A variation of the arc welding principle, plasma welding not only uses the electrical current to generate huge amounts of heat (five times greater than standard arc welding), which can create an incredibly fast, versatile welding system that works on a wide range of metal thicknesses.
Much of the technology used for plasma welding is also used in plasma cutting, a fast, accurate steel cutting process.
- Gas Welding
Gas welding, sometimes known as oxyfuel welding, is primarily used for repair work and welding tubes or pipes.
Typically the process involves burning acetylene in oxygen, creating a 3100 degrees Celcius flame that is directly applied to two pieces of metal, one of which is often a metal filler material, which then cools together to form a precise join.
It was one of the first modern welding systems (whilst arc welding pre-dated it, a lack of coated electrodes made it less usable at the time) and is still often used for smaller jobs due to being relatively easy to use and inexpensive compared to arc welding equipment.
- Resistance Welding
Resistance welding uses a combination of electric current (similar to arc welding) as well as physical pressure to join metal parts together that are in contact with each other.
It is exceptionally quick (most welds take less than a second to form) due to the use of low-voltage, high current power sources.
Due to its efficiency, consistency, lack of filler materials required and ease of automation, this system is primarily undertaken in the car industry.
- Forge Welding
The oldest form of welding and metalwork, forge welding is where metals are heated up until they are softened, and are then forced together (often manually using varying types of hammers) until they form a metallic bond.
This process dates back to the Bronze Age, but can sometimes still be seen today, either as part of heritage smithing or automated, specific functions.
- Energy Beam Welding
Electron beam and laser beam welding techniques are modern, advanced processes that work similarly, primarily differing in terms of their power source.
They create a concentrated heat source that melts metals in targeted areas, allowing for deep weld penetration and tiny weld areas, very quickly, with a lot of room for automation.
This has also led to a hybrid production technique that uses both arc welding and laser beam light to create a welding system that is the best of both worlds.