The blast-furnace departments in the Salzgitter Stahl AG, SZAG, and at the Huettenwerke Krupp-Mannesmann GmbH, HKM, in Duisburg are of quite a similar structure and lay-out. Both operate 2 blastfurnaces with about 2500 m~3 workable volume and hearth-diameters about 11 m. In our report we explain our developments in the selection of the refractory bricks, the cooling of the hearth and taphole areas and the daily practice of the tappings. Different ways of taphole openings are in use; i.e. soaking bar technique, drilling with water and drilling with a special type of drill bit. The quality of the taphole mud has improved by far, especially since the inauguration of the slag-granulations in the two blastfurnace works. The monitoring of the hearth wear is an important item for the operator to make predictions of the state of the hearth and to decide when to start counter-measurements, like the addition of ilmenite. The way of hearth monitoring will also be introduced in this paper. Finally the refractory material of the outside taphole area and the way of maintaining this area in order will be mentioned.
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