Machining the refractories and constructing the lining of equipment for the vacuum treatment of steel

Conclusions A section has been organized at the Magnezit Plant for the machining and checkout assembly of MKhVP and MKhV refractories for VTS equipment. The section is equipped with a column- and-knee type milling machine, surface grinders, and stands for the checkout assembly of the bottom and roof of the vacuum chamber and the hood cover.The masonry elements are shaped and a high quality of masonry work for the lining of VTS equipment is achieved by cutting and grinding the refractory bricks with diamond tools during a checkout assembly of the masonry. A total of 30–50% of the bricks used in the lining are machined in this manner.The tools are AOSK-type diamond disk saws for cutting and a face-plate built up of diamond-bearing bars for grinding the refractories. The bonding substances of the tools is a hard alloy (M50). The granularity and concentration of the diamonds are not significant factors in the machining productivity and the finish of the machined surface. The refractories are machined without a coolant feed in the cutting zone.An investigation was carried out of the principal cutting parameters for magnesia refractories. The conditions for dry-machining refractories with an AOSK-type diamond disk saw bonded with M50 are as follows (horizontal feed of the work to the tool): cutting speed, 46–50 m/sec; feed, 0.8 m/min; depth of cutting, 60 mm; productivity, 480 cm²/min; and diamond consumption, 10–12 carat/m².Translated from Ogneupory, No. 7, pp. 17–24, July, 1977.     

The effect of degassing technology parameters and the quality of periclase-chromite refractories on their wear resistance in vacuum chamber lining

The results of an integrated study of external factors on wear resistance of periclase-chromite refractories in vacuum chamber lining are discussed. It is established that the mineral composition and structure of magnesian-spinellide refractories are the least liable to transformations. __________ Translated from Novye Ogneupory, No. 9, pp. 35–38, September, 2006.     

Choice of refractories for lining ladles with out-of-furnace treatment of steel

Refractories and Industrial Ceramics -     

Refractories of a fused periclase-chromite material for the wall lining of 100-ton arc furnaces

Conclusions The durability of a wall lining in 100-ton arc furnaces of MKhVP type refractories based on fused periclase—chromite material is 20–30% higher than that of a lining constructed of periclase—spinel brick produced from sintered magnesite and chromite ore.The chemical inertness, high resistance to attack by corrosive media, and the low content of low-melting silicates in the MKhVP refractories ensure that the rate of zone formation in the bricks is slow and the durability of the lining high.Bricks of fused periclase—chromite can be recommended as refractories for the wall lining of the arc furnaces of the Oskolsk Metallurgical Combine now being constructed.These refractories should also be subjected to testing in the roof lining of arc furnaces.Translated from Ogneupory, No. 7, pp. 26–30, July, 1978.     

High-alumina refractories for lining steel ladles (discussion)

Conclusions We developed and evaluated, in industrial conditions, a technology for the production of unfired, mullite-corundum refractories, and also fired, mullite-siliceous refractories with additons of chrome ore for lining steel ladles.The life of the 150-tonne steel ladles, with steel processing outside the furnace, when the ladles were lined with the experimental unfired mullite-corundum refractories, equals the life of the ladles lined with similar, industrial fired bricks. The same resistance (on average 20 pourings) was possessed by the ladles lined with the experimental mullite brick of improved quality. The resistance of the ladles lined with the experimental, fired mullitesiliceous refractory with the chrome additive was 26–27 pourings.To explain the effectiveness of using the newly developed refractories in the linings of steelcasting ladles, it is necessary to continue testing them in different metallurgical enterprises.The first part of the discussion was published in No. 8, 1988, and it was continued in Nos. 9–12, 1988, and Nos. 1–3 and 5, 1989.Translated from Ogneupory, No. 7, pp. 4–8, July, 1989.