Continuous casting control via drive monitoring

Abstract

The paper describes the investigation’s results of functional capabilities of the equipment testing systems as applied to the withdrawal roll drives provided with individual power supply using the frequency converter-asynchronous motor system. All the experimental investigations were carried out at the “Magnitogorsk Iron and Steel Works” (MISW). The statistical analysis of time diagrams and frequency-response curve of changes in instantaneous values of withdrawal roll drives load torques were used. The diagnostic signs of the withdrawal roll bending, occasional slippage along the slab, wear of ring seals, and teeth of the mounted gearbox on the basis of the analysis of the component range of spectrum density of changes in load torques were computed. It was found that variance inhomogeneity of scattering of load torque change for adjacent time intervals can be used as a diagnostic sign of the withdrawal roll occasional slippage along the slab. We considered the developed diagnostic methods for withdrawal roll drive equipment at continuous casting machines (CCMs) which provide the increase productivity due to decreasing of the CCM repair work downtime. A functional diagram and a generalized algorithm of the diagnostic system for equipment of the withdrawal roll were developed taking into account the characteristics of continuous casting of steel at a slab CCM. An experimental estimate was carried out to assess the efficiency of the developed diagnostic system.