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Developments in the continuous casting of steel have put increased demands on the refractories used in the tundish. Tundish working lining systems are required to provide the steel maker with a clean steel practice over a reasonably longer sequence, proper insulation, wear resistance, flow control and easy deskulling. In order to achieve these objectives, the tun dish lining material also advanced significantly. The present practice of using silica board as cold tundish working lining material in Durgapur Steel Plant has some limitations in the aforesaid requirements. This paper deals with a "dry tundish working lining system" which allows the steel maker to produce cleaner steel. This material contains around 80% MgO and resinous bond. This bond is activated at relatively low temperature (250°·300°C) to generate sufficient strength. The thickness of the working lining varies between 40 and 60 mm depending on tundish size and sequence length. Dry tundish working lining can be used replacing Si0 2 or MgO boards in cold tun dish practice. In addition, the other components of the tundish working lining, e.g. impact pads/ turbo-inhibitors, metering nozzles, dams are also looked into to match the higher sequence length. The system has been proven as a cost effective refractory solution for long multiple sequence casts. IntroductionThe tundish lining system plays a major role in determining the efficiency of the continuous casting process, both in terms of productivity and steel cleanliness. This can be achieved by reducing the down time of the caster. At Durgapur Steel Plant (DSP), the casting sequence is terminated mainly due to erosion of silica bo.qrds presently used as working lining of tundish and the maximum sequence length of 6 heats (7-8 h casting time) is obtained. After each sequence, a long time (around 2-3 h) is required for preparation of the machine to restart. This causes loss in production and productivity of the continuous casting shop.In order to eliminate the limitations of cold board lining, an advanced lining system comprising back-up lining, MgObased dry working lining, turbo-inhibiter etc is being introduced at DSP as a cost effective refractory solution for long multiple sequence casts.

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