Air-arc cutting

Air-arc cutting is also known as air-carbon cutting and employs a consumable carbon or graphite electrode to melt the material, which is then blown away by an air jet.

This process is useful for cutting a variety of materials, but it is most often used for cutting, and gouging aluminums, copper, iron, magnesium, and carbon and stainless steels. Because the metal is blown away by the air jet, it does not need to be oxidized. This process differs from plasma cutting operations because in air carbon cutting, an open, or unconstricted, arc is used, and the arc operates separately from the air jet [WeldGuru.com, "Let the Weld Guru guide you through the world of CAC, Carbon Arc Cutting", 2008, http://www.weldguru.com/CAC.html (April 17, 2008)] .

Air pressures for the jet usually vary from 60 to 100 psig. The carbon electrode can be worn away by oxidation from heat buildup. This can be reduced by coating the carbon electrodes in copper.

The images in the first external link below show a basic schematic of the process and the electrode holder. The sharpened carbon electrode is drawn along the metal, an arc forms and melts the metal. The air jet is then used to blow away molten material. This can be dangerous as the molten material can be blown substantial distances [Serope Kalpakjian, Steven R. Schmid, Manufacturing Engineering and Technology (Upper Saddle River, NJ: Pearson Prentice Hall, 2006)] . The process is also very noisy. As seen in the second image the air jet is controlled by an air valve on the electrode holder.

References

Related articles

*Gas cutting
*Plasma-arc cutting

External links

# SweetHaven Publishing Services, “Fundamentals of Professional Engineering”, 2001, http://64.78.42.182/sweethaven/BldgConst/Welding/lessonmain.asp?lesNum=7&modNum=11 (April 17, 2008).