Thermal cutting
The main method for thermal cutting is a cutting with Oxy-fuel torch. That process is utilised to cut stainless steel not necessairy of the top quality, because during the process occurs oxidization along with high heat emission in cutting area. That’s why that kind of cutting is applied only when the other’s are not available for some reasons. While cutting with plasma, the steel is melted down only in limited area with very high temperature (20000 – 35000 °F) in the result of very condensed plasma stream. By plasma, we mean highly ionized and strongly concentrated gas which builds plasma streamed inbetween electric-arch created among electrodes. Commonly used plasmogen is air.
As mentioned before, the plasma cutting process is based on melting down the steel and throwing out it debris with high density electric arch of plasma, which burns between infusibility electrodes and cutted object. Infusible electrode is made of copper with zirconium plate (or hafnium) and needs very intense colling down by air or water. The temperature of plasma stream depends of electric currency, arch narrowness degree and also a kind and ingredients of plasmatic gas.
For steel cutting are used only gas burners with iron arch. The spark on arch is obtained by high voltage electric impulse or by high frequency current. This makes possible to cut every conducting material (cast iron, steel, cuprum, aluminium etc.). Nonmetalic materials can be cutted only with plasma torches based on independent arch.
will be continued…
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categories: plasma, steel cutting |