Algorithm for designing asymmetrical rolling mode

Abstract

Sliding of the work rolls along the strip is one of the emergency operating modes of the stand, as a result of which the steady rolling process is disrupted and fluctuations in the tension and thickness of the finished strip occur. The work obtained a condition for eliminating roll slippage along the strip in the general case of the technological process, when the diameters of the barrels of the upper and lower work rolls are different. To do this, when calculating the parameters of the asymmetric mode, the following actions are implemented. First, the presence of a leading zone is assessed at the initial surface roughness of the roll barrel. If there is an advance zone in the deformation zone on both sides of the strip, then the fulfillment of the classical gripping condition is checked with the initial surface roughness of the barrels of both rolls reduced by 60%, thereby simulating further wear of this roughness.It has been established that the greatest influence on the occurrence of slippage in the current state of the work roll barrel surface will be exerted by a combination of technology factors – strip compression in the stand, strip tension. The process asymmetry factor has very little effect on the probability of occurrence of the emergency rolling mode considered in the work.As part of the study, the previously developed algorithm for designing continuous rolling technology was improved, taking into account the possibility of roll slippage, incl. when using an asymmetric process.An asymmetric rolling mode created using a newly proposed technique for designing process parameters is presented.The work also demonstrates the influence of the asymmetry factor on the structure of the asymmetric deformation zone. It is shown that with increasing strip tension, the effectiveness of the impact of the difference in the diameters of the barrels of the lower and upper rolls on the source decreases