On-line measurement method for various guide modes of vertical ring rolling mill

This paper analyzes the interaction modes and rules between ring and rollers in vertical ring rolling process, and then establishes mathematical models of ring geometric shape and size corresponding to various guide modes. Using the models, the accurate expressions of ring’s radius are derived. Furthermore, the geometrical surfaces which represent the relations of ring’s outer radius versus displacement of driving roller and measuring roller are constructed. To obtain simple formulas suitable for the Programmable Logic Controller (PLC), the precise and simple functions of ring’s outer radius in rolling process are derived based on the surface-fitting method. In addition, a reliable displacement measurement device which is composed of the raster rulers and PLC is also introduced. The results of this paper can supply a practical method for on-line measurement and process control of vertical ring rolling.