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Engineers and scientists in Russia and abroad are giving a considerable amount of attention to improving the quality of the rails being made by metallurgical plants. Rolling 100-m-long rails requires proper preheating of the continuous-cast semifinished products with a minimal temperature gradient along and across the products. A heating operation of the requisite quality is assured by the use of a level-2 automation system to heat the metal in the furnace.The walking-beam furnace in the rail-beam shop at the West Siberian Metallurgical Combine (EVRAZ ZSMK) came on line in March of 2006; it was designed to heat continuous-cast semifinished products to 1180-1250°C for subsequent rolling. The semifinished products, with a 300 × 340 mm cross section and a maximum length of 5100 mm, were arranged in two rows inside the furnace. The rated productivity of the furnace was 250 tons/h. The furnace has nine temperature-control zones. It is fired by natural gas fed into the furnace by means of GR-type burners.The decision to have the rail-beam shop at EVRAZ ZSMK make rails 100 m long made it necessary to reconstruct the walking-beam furnace. The following major changes were made in April-August 2012 in order to provide the mill with a quality preheated semifinished product up to 9000 mm long for rolling into 100-m-long rails: the furnace's burners were replaced, an additional stationary beam was installed in the furnace, the regimes used to heat the metal were revised, and a new automation system was created.One of the factors that affects the production of quality rolled products -and even more so quality rails -is the uniformity with which the semifinished products are heated in the furnace prior to their rolling. To make sure that the heating is uniform along and across the semifinished products in the different heating zones of the furnace, the GR-type burners which were installed previously were replaced by flame-less TSX burners (Fig. 1). These burners ensure the formation of a uniform temperature field in the furnace's working space and, thus, also provide for uniform heating of the semifinished products.A level-2 automated system was installed to control the operation of the furnace, the system including a mathematical model of the heat transfer which takes place inside the furnace. The system makes it possible to calculate and then initiate a heating regime for each semifinished product that heats it to the prescribed temperature. The system automatically regulates heat input to each furnace zone in relation to the grade of steel of the semifinished product (bloom), the positions of blooms made of different grades of steel, and mill productivity and downtime. Figure 2 presents a diagram of the scheme that the level-2 automated system uses to control temperature in the furnace zones. Figure 3 shows one of the screen displays reflecting the operation of the furnace with the automated system installed. In addition to the values specified for the optimum heating temperature, the display provides complete information on...