Use and prospects of plate casting-rolling modules

Abstract

Mini-mills and CRMs have come into use for several reasons. The energy crisis in the 1970s intensified the effort tc develop and introduce energy-saving technologies such as the hot-charging of slabs into the reheat furnaces of hot-strip milh (HSMLs) in slabbing-mill -- HSML complexes. This practice was widely introduced in the USSR in the t970s. For example the percentage of slabs charged hot into the furnaces of the 1680 mill at the "Zaporozhstal'" combine increased 88%. Ener~ was also saved by transit (direct) rolling, with slabs being sent directly from the slabbing mill to the HSML and by-passing the reheat furnaces. These methods were later incorporated into continuous-caster -- HSML complexes and were used to the greatest effect on the largest scale in Japan. However, use of the given technologies required the development of various devices, accessories, and transport equipment, beginning with the continuous caster and ending with the finishing group of stands. Also, modifications had to be made to the production process along the entire line. By the middle of the 1980s, a fundamental reconstruction of the entire production cycle (the rebuilding of individual mills or even whole shops, since the problem of further reducing energy, labor, and material costs was not being resolved) was needed at large metallurgical combines with an annual production of 4 million tons or more. However, such reconstruction required an enormous amount of money.