Research On The Key Technologies Of Realization Of Schedule Free Rolling On Basteel1880HSM

For a long time, various state enterprises try their best to break the limitations of traditional rolling schedule, so that achieving schedule free rolling (SFR) in hot strip rolling mill. Baosteel1880HSM is a new line which put into use in2007. This line is equipped with long stroke Work Roll Shift (WRS) and Online Roll Profiler (ORP), it already has the basic conditions of SFR if only considered from the device configuration. However, there are many problems during the process of promoting SFR after production, such as ORP couldn’t use normally, the original design of WRS couldn’t meet the cross-rolling, lack of WRS and ORP joint control strategies,and the model of FSU(finishing mill setup) and PFC(profile and flatness control) cann’t adapt the frequent change of steelgrade and specification, all these problems restricted the realization of SFR. And after the heat load test of1880HSM, the product structure become very complex as a result of the rapid expansion of specifications, and customers require high products quality, which are even more restricted the realization of SFR.The paper firstly studied the using technology of ORP and optimized the grinding process and control technology of ORP. On that basis, the paper took the central region of roll as the research object, combined with the strip width and roll shift strategy proposed high-precision compound control technology of online roll profile, achieved the good roll profile in the region of roll contacted with strip, and strip shape can satisfy the quality requirement in large expansion and the scale of same strip width.Aimed at the problem that original designed for roll shift strategy can not meet the requirements of cross-rolling, the paper optimized the using technology of WRS. The paper also developed the roll shift strategy which can adapt the conventional rolling and the roll shift strategy which can adapt to cross-rolling when rolling order change.Above strategies can adapt to the SFR about1880HSM many varieties mix cross-rolling and the same width assemble production.By combining two technologies of ORP and WRS, eliminated the roll step dispersion between rolling region and non-rolling region of roll, ensured the smooth profile in strip-pass zone which is beneficial for the control of products edge drop especially wider strip. The paper also created the conditions for realizing inverse width rolling from narrow to wide. Owing to the frequent jump of strip thickness, hardness and width in SFR impacts the model setup precision, this paper optimized the setup model of APFC and FSU, improved the capability of model high-precision setup, reducing the influences of steel grade, specifications changes in setup calculation, all of these lay the foundation for the realization of the schedule free rolling.