System of Control over the High-Speed Wire Blocks Setup (ESCB)

RPC «Donix» developed an electronic system of control over the high-speed wire mill blocks setup (ESCB), including control over the rolling mill kinematic parameters and monitoring of the entry guide rollers operation. The system is based on the measurement of angular speeds of the block entry guide rollers.

Independent electronic system ESCB ensures the following control functions:

the pre-emergency condition of the rollers’ bearings is monitored by speed graphs;
the roller jamming is detected;
the compliance of the gaps setup in the roller guides with the roll gaps setup in the stands is checked;
the kinematic conditions of the block operation are controlled.

The speed graphs are saved to the computer in case if the actual speeds deviate from the rated speeds with the possibility of further analysis.

The system monitor interface is shown at Figure 1.

It includes two windows for the rolling process speed schedule presentation.

Virtual roller speeds for each controlled stand and rotations of the block motors are presented in the first window (Fig. 1a) as bar graphs. Virtual linear speeds of each roller are presented in the second window as line diagrams (Fig.1b).

Fig. 1а Operator monitor interface, Graph tag

Fig. 1b Operator monitor interface, Diagram tag

To facilitate the operator’s work the system is provided with the function of logical analysis and voice signals generation, characterizing the location and the cause of the guide deviation from the normal operation conditions.

The system of control over the kinematic parameters will increase the mill efficiency by means of reducing downtimes, rejects due to the entry guide rollers jamming in the mill blocks, and by means of reducing the bad quality wire rod production.

We developed a portable electronic system of the block optimal setup (ESOS). The system simulates kinematic and power conditions of rolling in the block. The system calculates the tension, the rolling moment, the motor current and the wire rod dimensions at the ends and in the main part of the coil. The system was developed for high-speed wire blocks in addition to the ESCB system.

The model can be easily adapted to the block-specific conditions by means of adaptation coefficients.

The ESOS system determines optimal roll gaps for all the stands in the block taking into account the specified values of kinematic mismatches and the values of the finished wire rod dimensions. Pass dimensions, nominal section diameter, chemical content of the steel, temperature at the block entrance, gear-box characteristics, motor speed and roll diameters serve as input data for the calculations.

Output data include the rolls gaps, tension, wire rod dimensions, motor load. The calculated setup modes ensure the minimal interstand tensions which now depend only on the equipment condition and the specified accuracy of the wire rod cross-section dimensions along the coil length.

The ESCB system has been successfully tested on wire mill 150 of CJSC «Makeevka Metallurgical Works» where it was used to monitor the pre-emergency condition of the rollers’ bearings by means of the visual and program monitoring of speed deviations from the rated speeds.