TEMPERATURE COMPARISON CHART
The chart herewith reproduced attempts to represent visually the correlation between several items related to the Centigrade and Fahrenheit temperature scales. These scales are so arranged that any horizontal line will intersect them at the same temperature level. Similarly the melting points of several common metals and oxides are noted at their respective levels. To the left are drawn millivoltage scales which show the millivoltages developed by three commonly used thermocouples when their cold junctions are at zero degrees Centigrade and their hot junctions at the temperature level shown by the temperature scales at the right. The temperature range covered by'the use of pyrometric cones (Seger cones) is shown and the temperatures thCy indicate are marked with the corresponding cone numbers. The iron-carbon equilibrium diagram shows the range ordinarily used in hardening operations. The alumina-silica equilibrium diagram is complete and the composition range of refractory bricks made from these two oxides, indicated. Only rough approximation is claimed for this comparison chart, but the author believes the approximate relations between the various items related to the temperature scales are clearly visualized by its use.
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NORMAL L U l T INDUCTION TYPE FURNACE
FIRED FURNACES
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