System of Control over the Rolling Mill Practice and Speed Schedules of a Roughing Mill

The system increases maintainability of the roughing mills equipment by means of eliminating the risk of occurrence and development of unstable and emergency modes of operation.

The system's functions are:

to generate the signal for speed setting for top and bottom roll drives.
to take up mechanical gear clearances by means of generating a nonlinear signal for electric drives acceleration and deceleration setting.
to change acceleration and deceleration values during rolling with a view to minimizing the rolling cycle and preventing the slippage.
to generate signals for limitation of the main drive rotation rate in order to ensure stability of biting and rolling.
to separate "biting/rolling" schedules.
to control the drafting schedule realization, monitoring the roll gap and billet movement through the passes.
to control mismatch of the currents and speeds of top and bottom roll drives and to adjust the setting signals in case of such mismatch.
to trace threshold values of reductions, to abort the equipment operation in case of the mill operator's 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 for the operator.
to record the events and accumulate the statistics.
to record the prehistory of emergency situations development and to retain it for further processing and analysing.

Hardware:

Control computer based on an industrial workstation AWS 824TB, with Celeron 466 processor, 16 MB on-line storage and 32 MB hard disc, Ethernet network adapter.
Galvanic isolation modules Analog Device version 5B, Advantech ADAM 3014, Grayhill 70G.
Uninterruptible power supply APC Smart UPS (700 VA)
Coupling modules with custom-made sensors
Emergency processes recorder "RECON".
Industrial computer Advantech IPS 6806S.

Software: The object-oriented software, written in "С++" language, functioning in the operational system QNX.

The system is implemented on the roughing mill 950/900 of JSC "Istil" (Donetsk, Ukraine).

The system can be efficiently used on any reversing duo roughing mills of metallurgical works.