In recent years, JISCO has broken through the technical blockade, broken the technical barrier, jumped out of the technical trap, adopted a new technology, successfully developed a special transformation of non-magnetic steel, filling the JISCO manganese steel technical gap in the field, the original non-magnetic steel production process to achieve the leading domestic level.
High Manganese non-magnetic steel has the advantages of low-temperature impact resistance, low magnetic and non-magnetic stainless steel, excellent mechanical properties of carbon steel, easy welding, and so on, and is widely used in the manufacture of the key equipment of large transformers. With the continuous development of the power transmission and transformation industry in our country, the demand for non-magnetic steel is increasing day by day, and it has become a competitive target for all steel enterprises at home and abroad. However, the content of manganese and aluminum in non-magnetic steel is 25% and 2%, which are 20 and 200 times higher than that of conventional steel, respectively, the conventional production process can not guarantee stable production requirements.
Although smelting is difficult, to enhance product competitiveness, JISCO will focus on non-magnetic steel. In 2017, the development of non-magnetic steel began planned, 2018, the start of industrial production. During the smelting process, the technical staff of the mill strict control, and operators keep a close eye, in as long as 12 hours of strict defense, the first furnace without magnetic steel was successfully out.
“Smelting was successful, but it took more than five times as long as conventional steel smelting,” said Yang Xinlong, head of product development at the Wire Rod Research Institute of the Steel Research Institute, “Furnace production is time-consuming, labor-intensive, and resource-intensive and is not the optimal production process.”
Based on many arguments and field tests, the technicians put forward the idea of“Changing furnace”. They found that EAF production is“Static” smelting, alloy in the furnace“Can not move”, the uniformity of molten steel is not good, the use of non-of smelting new process, it can ensure that all kinds of alloys are“Mixed” more evenly under the dynamic action. More importantly, the smelting time is greatly shortened under the new process, and the alloy yield can be up to more than 95%.
Under the guidance of the new technology, the R & D personnel spent three years, mastering the key technology of smelting high-manganese high-aluminum non-magnetic steel, successfully R& D special transformation non-magnetic steel, filling the technical gap in the field of JISCO manganese steel, it is the second non-magnetic steel continuous casting and rolling production and batch supply enterprise in China.
R & D success is not the end, stable production is the goal. The technical staff of the Rolling Mill, Steel Research Institute, and Stainless Steel Branch make great efforts in the aspects of market research, process route design, technical scheme discussion, and process optimization, and finally break through the technical bottleneck, low-cost, high-efficiency and short-flow stable production of non-magnetic steel is realized.
After testing by the State Steel Material Testing Center, Xinjiang Quality Supervision Bureau, Lanzhou University of Technology, University of Science and Technology Beijing, and other authorities, all the properties of non-magnetic steel of JISCO have met the standards, the original non-magnetic steel production process has reached the leading domestic level.
“The successful development of 20MN23AIV, a high-manganese and high-aluminum non-magnetic steel is just a ‘stepping stone for Jisco to enter the manganese steel field. In the later stage, Jisco will strive to make a breakthrough in the development of LNG High Manganese Steel and other steel grades based on non-magnetic steel, laying a foundation for greatly improving the production efficiency of Jisco,” said Jiang Jun, general manager of Hongxing Company’s Mill.