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TECHNOLOGIES AND AUTOMATIC CONTROL SYSTEMS FOR
THE PROCESSES OF ROLLING AND HARDWARE PRODUCTION
THE SYSTEM OF CONTROL OVER THE TECHNOLOGY AND THE
SPEED SCHEDULES OF THE ROUGHING ROLLING MILL
The system's purpose is to increase the maintainability of the breakdown rolling mills equipment by means of preventing the occurrence and development of unstable and emergency modes of operation.
The system's functions are:
- to generate the signal of speed assignment for the top and bottom roll drives.
- to take up mechanical gear clearances by means of generating the nonlinear signal of acceleration and deceleration assignment for electric drives.
- to change the acceleration and deceleration values during the rolling process with a view to minimizing the rolling cycle and preventing the slippage.
- to generate signals of speed limitation for the main drive rotation in order to ensure stability of biting and rolling processes.
- to separate the "bite / rolling" schedules.
- to control the roll gap and billet movement over the passes according to the draughting schedule.
- to control the errors in the currents and speeds of the top and bottom roll drives and to adjust the assignment signals in case of development of such errors.
- to trace the limiting values of the draughting process, to abort the equipment operation in case of the mill supervisors' gross errors and to generate corresponding messages.
- to display the main drives operation modes and to generate messages for the duty attendant of the control room and the supervisor.
- to record the events and accumulate the statistics.
- to record the prehistory of emergency processes development and to retain it for further processing and analysing.
Hardware:
- Control-computer based on the industrial workstation AWS - 824TB, with Celeron 466 processor, 16 MB on-line storage and solid-state disc with 32 MB capacity, Ethernet network adapter.
- Galvanic isolation modules Analog Device 5B, Advantech ADAM - 3014, Grayhill 70G.
- Uninterrupted power supply APC Smart - UPS (700 VA)
- Coupling modules with custom-made sensors
- Emergency processes recorder "RECON".
- Industrial computer Advantech IPS - 6806S.
Software tools: object-oriented software environment, written in "C" language, functioning in the QNX real-time operational system.
The system is introduced on the breakdown mill 950/900 of the Joint Stock Company of the Closed Type "Istil" (Ukraine, Donetsk). The improved version of the system - with direct digital control over the rolling mill drive - is being introduced at the Blooming Mill-2 of Krivoi Rog Integrated Mining and Metallurgical Works "Krivorozhstal".
The system can be efficiently used on any blooming and slabbing mills of metallurgical works.
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