Strategy of vibration diagnostic control of mill equipment condition

The task of mill equipment with the vibration diagnostic system is relevant because of the need to enhance maintenance efficiency and reduce essential equipment failures. The main peculiarity of vibration processes appearing in the mill process line has been distinguished: appearing longitudinal vibrations transmitted through treated metal. Furthermore, approximation of longitudinal vibration frequencies to the strip natural frequency results in resonant vibrations. It causes strip defects and may trigger fault trip of the mill due to its breakage. The paper formulates requirements to the stationary system of the mill equipment vibration monitoring. It substantiates the strategy of vibration control based on solving two functional tasks: vibration monitoring and diagnostics. Tasks of the functional sub-systems are considered. The paper also lists mill stand defects to be determined with vibration diagnostics and criteria for their detection at the early stage. It provides the example of practical implementation of the developed strategy at establishment of the stationary system for diagnostic monitoring the equipment of the main electric drives of 630 mm five-stand cold-rolling mill at OJSC Magnitogorsk Iron and Steel Works. Locations for sensor installation at the mill stand equipment have been determined. The system functional structure is under consideration. Display representation of results of parametric vibration diagnostics is provided. Results of industrial introduction of the developed system are described.