What is the role of compressed air in carbon arc gouging? What problems can insufficient air pressure cause?

What is the role of  compressed air in carbon arc gouging? What problems can insufficient air pressure cause?

Compressed air plays a vital role in carbon arc gouging, mainly including the following aspects:

• Blowing off molten metal: During the carbon arc gouging process, the arc heats the metal locally to a molten state, and the compressed air blows the molten metal away from the gouging groove in the form of a high-speed airflow, thereby forming the desired shape and size. Without the blowing effect of compressed air, the molten metal will re-solidify in the gouging groove under the high temperature of the arc, and the purpose of gouging cannot be achieved.

• Cooling effect: While blowing off the molten metal, the compressed air also cools the metal around the gouging groove. This helps prevent metal overheating, reduces the scope of the heat-affected zone, and reduces the possibility of material deformation. It can also quickly cool the gouging groove surface and improve the surface quality.

• Stabilizing the arc: A proper compressed air flow can help stabilize the arc. It can blow away the ionized gas around the arc, making the arc more concentrated and stable, which is conducive to improving the efficiency and quality of gouging. A stable arc can ensure uniform heat distribution and make the size and shape of the gouging groove more stable.

If the air pressure is insufficient, the following problems will occur:

• Incomplete blowing of molten metal: When the air pressure is insufficient, the blowing force of the compressed air is insufficient to completely blow the molten metal away from the gouging groove, which will cause a large amount of slag and molten metal that has not been blown away to remain in the gouging groove. This will not only affect the surface quality of the gouging groove, but may also cause defects such as slag inclusions, which will bring difficulties to subsequent welding or other processing procedures.

• Poor cooling effect: Due to insufficient air pressure, the cooling effect of compressed air is weakened, and the metal around the gouging groove cannot be cooled in time and effectively. This will expand the heat-affected zone and increase the possibility of material deformation. It will also affect the hardness and organizational structure of the gouging groove surface and reduce the performance of the material.

• Decreased arc stability: Insufficient air pressure will prevent the ionized gas around the arc from being blown away in time, resulting in arc diffusion and poor stability. Unstable arcs will cause uneven heat distribution, make it difficult to control the size and shape of the gouging groove, reduce gouging efficiency, and even cause arc breaking, affecting the normal gouging process.

• Reduced production efficiency: The combined effect of the above problems will lead to a decrease in the overall efficiency of carbon arc gouging. Since more time is required to clean the gouges, deal with defects and adjust the gouging parameters, the production schedule will be affected, increasing production costs and processing time.