A high degree of efficiency can be achieved in automating the various operations involved in the manufacture of rolled products by providing for integrated, interdependent monitoring and control of the entire mill line, rather than individual sections and local components.The Nizhnedneprovskii Pipe Plant has introduced an automated system to monitor and control the equipment on the delivery side of its 140 tube-rolling unit. The system was designed and built by the Kvantor Scientific-Industrial Association together with the State Pipe Institute of Ukraine and the Nizhnedneprovskii Pipe Plant.The equipment of the complex (a tube-reducing mill with 20 stands, in addition to mechanisms and a saw for cutting pipes up to 20 m long to measured lengths during) determines the final dimensions and commercial characteristics of the reduced pipes.The following operations are performed on the 140 tube-rolling unit: heating of a solid circular semifinished product to 1200~ piercing; longitudinal rolling in two successive stands to a diameter of 130-175 mm; heating of the semifinished tube and its rolling to its final dimensions in continuous multi-stand mills; reduction (to a diameter of 60.3-95 mm) and sizing (to a diameter of 89-168 ram). The speeds of the electric drives of the stands of these mills are adjusted and maintained in a certain relation to one another during roiling. The speed ratios are set so that the linear velocity of the rolls matches the increased velocity of the tube alter each stand as its diameter is decreased to the required value in the rolls. To decrease or maintain the wall thickness of the initial tube, the speeds of the rolls and the electric drives are regulated so as to apply sufficient tension to the hot tube between the stands of the mill (reduction with tension).The flying saw on the delivery side of the tube-reducing mill cuts the tube leaving the mill to measured lengths with toothed rotary disks. The disks and the electric drive are mounted on the rotating frame of the saw table. The electric drive of the table is controlled by a program which matches the linear velocities of the saw disk and the moving tube. This prevents breakage of the disk and provides enough time to rotate the table in order to allow passage of the ends of tubes of the prescribed measured length.The above-described operating regimes of the electric drives of the tube-reducing mill and the flying saw are realized by an automatic control system based on PTK UNIKONT software-hardware systems. The universality and reliability of the hardware part of PTK UNIKONT systems, the fact that it is protected from the environment and is IBM-compatible, and the sophistication of the application programs make it possible to realize almost any methods and algorithms for monitoring and controlling metallurgical processes. Regimes which entail simultaneous monitoring and control of the electric drives of the multi-stand tube-reducing mill and the flying saw have been developed and implemented on the basis of a single PTK UNIKONT system...

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