A welding arc uses an electric current to melt and join metals pieces of metal together. The process involves very high temperatures that melt the parts before letting them cool down and form the weld.
Welding arcs are incredibly hot and produce enough heat that is needed to join pieces of metals into one piece. In fact, it is almost impossible and dangerous to deal with a welding arc without proper personal protective equipment, especially for your eyes.
Although different materials will require varying temperature levels, most applications often require an arc temperature of up to 10,000°F. This is super hot!
Generally, arc welding uses either DC or AC power supply to produce enough heat to melt filler metals and form the joint. And because of this, arc welding is considered one of the most efficient and precise welding methods.
How hot is a welding arc?
As we have earlier mentioned, a welding arc is around 10,000°F, but it can reach a high of up to 15,000°F or more depending on the welding technique and metals being welded.
On the other hand, MIG and flux-cored welding do not produce a lot of spatter, but the arc is very hot nonetheless. They may also create sparks, so you may want to take extra care to avoid pumping shielding gas into the flames.
TIG welding, on the other hand, uses a non-consumable electrode to generate the heat needed to melt the metals. And just like other processes, the welder creates an arc between the workpiece and the electrode, but it is much cleaner.
What makes welding to be so hot is because the heat is localized in one area i.e., the point of contact. Upon reaching the weld zone, the arc radiates the heat in all directions, and this is how the welder is able to feel the heat.
Ideally, the specific composition of metals will determine the amount of heat applied and the length of time it maintains the temperature. In addition, most metals are good conductors of heat, so heating the weld puddle and the area around it is rather faster.
It is important to note that the part closest to the arc experiences more heat. However, the temperatures may begin to decrease as you increase the distance from the weld. Also, most metals expand when heat is applied, but this corresponds with the intensity of the heat applied.
Is a welding arc hotter than the sun?
Not really. No matter how hot a welding arc might feel to you, the sun is way much hotter. A welding arc can cause instant damage to your skin and eyes, but that’s because it is only some feet away from you. On the other hand, the sun is a million miles away from the earth, which reduces its intensity.
Furthermore, the distance plus the water vapor in the atmosphere has also greatly reduced its hotness. If you travel to space without proper solar protective equipment, the sun rays will likely roast you alive. So, if we were to measure the radiated heat from an equal distance, then the sun is the unquestionable winner of the battle.
The distance from earth is what makes us enjoy its warmth and easy to look at it (however, it is not advisable to look at the sun directly).
For the same reason, you should never try to look at a solar eclipse with naked eyes.
In terms of brightness, the sun is also considered to be way brighter than a welding arc. However, a welding arc is still considerably bright and can cause irreversible eyes damage because of its proximity to the welder.
A welding arc often involves exposed flames and sparks, which puts you at risk of burning yourself.
The Bottom Line
Different welding processes have their own share of benefits and downsides, but one thing makes them equal: they are pretty hot. This means that they have the potential to cause bodily injuries and damage the property and the environment around them. As such, it is important to adopt a safe welding program to stay out of harm’s way.