In pig iron production unit of integrated steel plant, excess liquid metal accumulated due to downstream disturbances needs to be processed immediately to keep the metal production running. Granshot iron granulation technique developed by UHT, Sweden, 1970 has been found to be a viable cost competitive route. It is named as Granulated Pig Iron (GPI) production route. In this process, the liquid metal stream emerging from tundish strikes a refractory precast shape named as "SPRAY HEAD" through a flow control refractory tundish nozzle. The GRANSHOT process converts liquid metal into granules by rapid solidification in water. Metal granules are homogenous in composition, easy to handle, store and transport. In this process, hot metal discharged from torpedo ladles into a runner followed by a tundish and the stream of hot metal falls from tundish on a refractory striking disk, called spray head, hot metal pea/ balls thus generated fall into the water bath to form solid metal pea, as shown in Fig. 1 b) and 1 c). As the molten liquid strikes over the spray head refractory, the quality of refractory plays a vital role for safe operation of gran-shot. The spray head experiences extreme high impact of hot metal stream, severe thermal shock. Any failure or breakage of the spray head would cause severe operational hazards as the hot metal stream would directly falls into water bath.
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