Society of Glass Technology · [Sheffield] · leaf 569
sistant material between the electrodes and thecrucible. It was possible to obtain a maximum temperature of2300° in twenty minutes. The transformer used gave current atfrom 20-7 to 38 volts with 65 to 120 amperes. The cost of runningdid not exceed 30 cents per hour with power at 10 cents per… … Fig. 118. chambers at each side with a separate air-supply for each. Inthe tunnel kiln shown, gas from the channel, a, enters a combustion
Glass
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