Influence of Carbon Cooling on the High-Current Carbon Arc.

摘要

The influence of carbon cooling, especially of the positive carbon, on a high-current carbon arc was studied systematically. An experimental super-high-intensity carbon (No. 070) manufactured by the National Carbon Company was used in the investigation. The technical advantages of carbon cooling are increased steadiness of the arc and its radiation, considerably reduced positive carbon consumption, a shallower crater, and the possibility of using higher wattage and obtaining greater brilliances, while the main physical effects are marked decreases of arc voltage and positive carbon evaporation. The empirical relations between current, voltage, net arc wattage, gross arc wattage, crater brilliancy, carbon consumption, light efficiency, and crater depth for the cooled and the uncooled arc are presented in the form of graphs based on more than 1000 measurements. The differences between arcs with cooled and uncooled carbons are explained as a consequence of chemical and structural changes in the carbons that result from the difference in temperatures near the burning end. This explanation has been confirmed by X-ray studies. (Author).