DEFORMATION OF FINISHING STANDS TUBE BILLET MILL (TBM) 900/750

Abstract

The rolling square and round billets is almost completely replaced by continuous casting machine (CCM) products now in world. Under these conditions, the tube billet mills (TBM) are forced to change their assortment and producе new types of rolled products. The question arises of compliance of the equipment with the requirements of the section rolling mill during the repurposing of the TBM. It becomes relevant compliance with the stiffness of stands. The high stiffness, knowledge, and control of the “spring” of the mill improves the accuracy of rolling, reduces the amount of metal spent on setting. The work aims to study the finishing stands TBM 900/750 PJSC “KAMET-STEEL” for compliance with the stiffness requirements for section mill stands, and to determine the possibility of rolling profiles with increased requirements for dimensional tolerances in them. The work proposes a new theoretical and experimental method for determining the rigidity of a rolling stand. The use of this method made it possible for the first time to determine the stiffness of stands 750 of the TBM 900/750 of PJSC “KAMET-STEEL”. It is shown that the rigidity of stands 750 meets the requirements of section mills. Based on the proposed computational and experimental method of determining the rolling stand “spring”, a mathematical model was developed for calculating the gap of the stands 750–1, 2, and 3, which is implemented in Excel. This model allows you to determine the gaps in stands 750–1, 2, and 3 before rolling with an accuracy of up to 5%. The results of the work allows for a reduction of the volume of metal for setting up the stand by 50% (by 2,4 tons). Eventually, the expense ratio shall be decreased by an average of 0,8%.