TECHNICAL TOOLBOX ISSUE 43 Contact: STEVEN HARKER [email protected] better off not used. Something that I’ve no idea is true or not or was just used to justify the process. As the cast and rammed refractory lining came in, new ladle preparation prcoesses were required. As I understand it, mordern linings are less tolerant to thermal shock but if treated correctly give a longer life and better performance than the previous types of lining. From speaking to refractory suppliers, I am wondering if correct preheating is now more for the benefit of the refractory lining than from thermocouple feedback, so the preheater is not blasting out a full flame if the ladle doesn’t need it. Neither is the refractory in danger of being “over cooked.” However, unless additional gas flow devices are installed it is very dfifficult to give accurate fiigures on how much less gas the modern units use when compared to, say, a simple gas/air nozzle system. a metallurgical perspective. The usual comment from refractory companies is that preheating of the ladle lining, should be as extended as possible, giving time for the heat to soak into the refractory. Also, the general preheat temperature is in the range of 1470°-1830°F (800°- 1000°C) which is still away below the temperature of molten ferrous metal, but it is in the range that the refractory companies like. Most of our preheaters use a modulating gas system, with a temperature control via
RkJQdWJsaXNoZXIy NDI4Njg=