Why is there a humming sound effect during arc welding?

4346 why is there a humming sound effect during arc welding

Arc welding is a process that involves the use of intense heat generated by an electric arc to melt and join metals. During the welding process, there is a humming sound that can be heard. This humming sound is a result of the interaction between the electric arc and the surrounding air.

The electric arc produces an intense heat that causes the air surrounding the welding area to expand rapidly. This rapid expansion of air creates a pressure wave that travels through the air, producing a humming sound. The frequency of the sound depends on the frequency of the pressure wave, which in turn depends on the intensity of the arc and the distance between the arc and the listener.

The humming sound produced during arc welding is often referred to as the “arc blow” or “arc buzz”. This sound can be quite loud, and can be a nuisance to those who are working in close proximity to the welding area. In some cases, the sound can even be strong enough to cause vibrations in nearby structures.

There are several factors that can affect the intensity of the humming sound during arc welding. These include the current and voltage of the welding equipment, the type of metal being welded, the distance between the welding area and the listener, and the presence of any obstacles or barriers that may interfere with the flow of air around the welding area.

In addition to the humming sound, arc welding can also produce other types of noise, such as hissing, cracking, and popping sounds. These sounds are also a result of the interaction between the electric arc and the surrounding air, and can be caused by factors such as the presence of impurities in the metal, the type of welding electrode being used, and the welding technique employed.

In conclusion, the humming sound that is heard during arc welding is a result of the rapid expansion of air caused by the intense heat of the electric arc. While this sound can be a nuisance, it is a normal part of the welding process, and can be minimized through the use of proper equipment and techniques. It is important for welders and those working in close proximity to welding areas to take appropriate measures to protect themselves from the effects of welding noise, including the use of hearing protection and the implementation of noise control measures.


  • American Welding Society. (2013). Welding Processes Handbook. Miami: American Welding Society.
  • International Organization for Standardization. (2008). Acoustics – Determination of Sound Power Levels of Noise Sources – Engineering Methods for Small, Movable Sources in Reverberant Fields – Part 2: Methods for Special Reverberation Test Rooms. Geneva: International Organization for Standardization.