The dummy bar largely determines the design of the guiderails in the technological line of a continuous-casting machine (CCM), as well as the composition of the equipment and the sequence of casting operations. In addition, the dummy bar influences the quality of the continuous-cast billet in the initial period of casting, as well as the operation of the rocker mechanism for the mold and the tractional and straightening machines. In modern CCM with a radius of curvature up to 14 m, the use of a rigid arc-shaped dummy bar entails many difficulties. In prolonged use, the radius of curvature increases, which produces stress in the arc-shaped bar in the tractional rollers. Removal and storage of the dummy bar is hindered, as well as crane operation in the immediate vicinity of the tractional and straightening machine. A rigid dummy bar cannot be used on a CCM with multipoint flexure of the ingot, where straightening occurs in the two-phase state, while the secondary-cooling zone has a variable radius of curvature.
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