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For the linings of high temperature steel teeming ladles more and more use is being made of magnesia parts* [1][2][3][4][5][6][7][8], the use of which makes it possible to substantially increase the lining life of ladles and provide outside-the-furnace treatment of steel. The Eastern Refractory Institute has developed a new form of periclase-chromite concrete ladle parts, type PKhBK-851.The parts were made in Magnesite Combine in a quantity of 241 tons and tested in three metallurgical plants.The original materials (Table i) were crushed periclase-nhromite and chromite-periclase parts, microgranular periclase (magnesite) powder, calcined periclase (caustic magnesite), and sodium polyphosphate (GOST 20291-80).The parts were produced using the following method.To prepare the sodium polyphosphate solution cold water was poured into the tank, the sodium polyphosphate was added, and it was bubbled with compressed air for 8-16 h. The 15-0 mm fraction crushed parts were poured into the mixing rolls of the press, the sodium phosphate solution was added, and it was mixed for 5-7 min. Then to the mixture was added the finer than 0.06 mm fraction microgranular periclasepowder of the PK mixture and it was mixed for another 5-7 min.The composition of the type PKhBK-851 concrete part mixture was 70-75% crushed parts, 25-30% microgranular periclase powder or PK mixture and sodium polyphosphate solution with a density of 1.45 g/cm ~ (above 100%) 3.5-4.5%.The consumption of sodium polyphosphate solution for a single bath (400 kg) was i0 liters and 1 ton of parts required 16 kg of dry sodium polyphosphate and 21 liters of water.