One of the main factors determining the longevity of bearings is contamination of steel with nonmetallic oxides. A relation between the oxygen content, the number of oxygen inclusions in bearing steel, and its operational properties has been established [1-4]. This entails tightening the requirements in standards and technical specifications on the oxygen content in bearing steels to no more than 15 ppm, and in some cases no more than 9 ppm. Accordingly, the development of a technology for the production of bearing steel containing no more than 12 ppm oxygen in the rolled product has been considered at Istil (Ukraina) Metallurgical Works. A carbon intermediate product is obtained by the usual technology in the electrosteel-smelting shop, in a DSP-100NZA or DSP-120 furnace with a Danark system, and subjected to out-of-furnace treatment first on discharge from the smelter and then in a ladle-furnace unit (LFU). Next, the liquid metal is sent for vacuum degassing in a vacuum chamber and bottom-cast into 3.43- and 5.6-ton ingots under heat-insulating mixtures.
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