| Popis: |
This paper deals with the polygonal deformation phenomena of rolls in a reversible hot plate leveler of the steel making machine experimentally and analytically. The plates leveled by rolls with polygonal deformation become so called defective products because the profile of deformed roll is transferred to the surface of plate. From the measurements of deformed rolls, two kinds of polygonal wear were found. Then, from the vibration measurement of a hot leveler in actual operation, natural frequencies of the hot leveler were determined and the process of the polygonization of rolls was observed. Finally, the authors analyzed a simple model theoretically, regarding the polygonal deformation phenomena as unstable vibration of the hot leveler system caused by time retardation accompanied by wear on the surfaces of rolls. A good agreement between experimental and theoretical results was also confirmed. |
