Welding is used across the globe in some way in nearly every industry you can imagine. Its used in industrial settings, open air environments, underwater and even in outer space. Welding is used on almost every scale by handymen and structural engineers. And because there are so many uses for welding, there are also many different types of welding, each suited to different jobs and purposes. Were going to take a look at some of the more popular kinds of welding.

Forge Welding
While not used as much as it was in the 19th century, there is still a place for forge welding today, especially when creating high-quality collectible knives and swords. This method of welding is one of the oldest around and relies on a process of heating and pounding metal. Forge welding is the craft employed by blacksmiths of old, making swords, weapons, horseshoes and many other day to day necessities.

Arc Welding
Arc welding relies on a welding power supply to create an electric arc between a positively charged electrode and a negatively charged steel place. The electrical current will jump through the resulting air gap and will create an arc of enormous heat capable of melting metal.

Arc welding is one of the most widely used welding methods around and has many different secondary branches including:

AC (Alternating Current) Arc Welding
DC (Direct Current) Arc Welding
Gas Metal Arc Welding (GMAW)
Gas Tungsten Arc Welding (GTAW)
Submerged Arc Welding (SAW),
As well as many other specialized methods.

Gas Welding
Unlike arc welding, which relies on electricity, gas welding uses gas (usually a combustion of acetylene and oxygen) to produce a welding flame that exceeds temperatures of 3000 degrees Celsius.

Gas welding is one of the planets oldest and most versatile welding processes, but has gone out of fashion in industrial applications over the recent years. However, it is still popular to use when welding pipes and tubing, as well as with completing some repairs.

Varieties of gas welding methods include:

Oxyfuel welding
Air Acetylene Welding
Oxygen Hydrogen Welding, and
Pressure Gas Welding.

Resistance Welding
Resistance welding uses the application of an electric current along with mechanical pressure to create a weld between two pieces of metal.

This method allows higher speeds, easy automation and is suitable for high production rates. However, the initial equipment costs and lower tensile & fatigue strengths temper out the payoff.

Resistance welding is used heavily in the automotive industry.

Energy Beam Welding
As its name suggests, energy beam welding is a category of welding which utilizes a beam of such high energy intensity that it is capable of melting and vaporizing metals. This process of welding uses electron or laser beams and is very useful for precision welding, drilling and cutting.

Solid State Welding
Our final category, solid state welding is very similar to forge welding in that it doesnt rely on the melting of metal to work. One of the most popular methods of solid state welding is ultrasonic welding, a process very similar to resistance welding, except instead of relying on an electrical current, vibration is used to create the energy output. Ultrasonic welding is used for making electrical connections out of aluminum or copper, and it is also a very common polymer welding process.

Other popular methods of solid state welding include:

Explosion welding (relies on the use of incredibly high pressure and is often used to join two dissimilar materials.)
Co-extrusion welding
Cold welding
Diffusion welding
Friction welding
High frequency welding
Hot pressure welding
Induction welding, and
Roll welding.

Between these many different welding methods (and many more we didnt identify) we are able to graft metals and other materials together in such a way that skyscrapers, space shuttles and automobiles can take shape. But, we can also do something as intricate as make jewelry. Weve been welding for millennia, and well do it for many millennia more.