SUBSTANTIATION OF CORRECTIVE ACTIONS FOR COMPENSATION OF DESCENDING CARBON IN STEEL DURING MANUFACTURE THE COLD-ROLLED FLAT PRODUCTS FOR FORMING
DOI:
https://doi.org/10.14529/met200307Keywords:
steel with low carbon content, semi finished hot-rolled product, temperature of the end of hot rolling, temperature of the winding, grain size, graininess, cold-rolled steel, defect “orange peel ”, total deformation during cold rolling, optimizationAbstract
The relevance of the work. There are situations in the practice of metallurgical production when steel melting with a chemical composition intended to complete the determined order is reassigned to the production of rolled metal from another steel grade. With the formal accordance of chemical composition of melted steel to the requirements for a different steel grade, crucial control parameters of process that are traditionally used for a new grade of steel, may turn out to be inappropriate for structural and phase transformations in steel with real chemical composition. To prevent the re-lease of non-conforming products is necessary to develop and apply operational corrective actions. The purpose of the work is selection and rationale of operational corrective actions in the production of cold rolled sheet products of quality classes CQ, DQ and DDQ of mild quality steel to compensate for the reduced carbon content in meltings assigned to complete the respective orders. Microscopy methods were used to study the structure and phase composition of steel with a carbon content of 0,008 – 0,04 % in hot-rolled and cold-rolled states. Data on the mechanical properties of hot-rolled and cold-rolled steel were obtained by standardized tensile test methods. Based on the test results, re-liable multiple approximations of influence of control characteristics of the technology on properties of cold-rolled steel were constructed, which were subsequently used in optimization of thickness of semi finished rolled product for cold rolling as a compensating effect at the fluctuations of carbon content within the above limits. The novelty of the work lies in the identification and rationale of corrective actions for a technological system in which cold rolling is carried out on a continuous four-stand mill with roll feed. The results of the work consist in determining the temperature of the end of rolling and the increment of the thickness of the semi finished rolled product as operation-al compensating effects at assigning steel meltings with a low carbon content for rolling into a tech-nological system with a continuous four-stand mill with roll feed. The practical significance of the work is to prevent the yield of non-conforming products at using the proposed solution in the pro-duction of cold-rolled steel of quality classes CQ, DQ and DDQ 0,6–2,0 mm thick.References
Frantsenyuk I.V., Frantsenyuk L.I. Sovremennyye tekhnologii proizvodstva metalloprokata na Novolipetskom metallurgicheskom kombinate [Modern steel rolled production technologies at the Novo-lipetsk steelworks]. Moscow, Akademkniga Publ., 2003. 208 p.
Benyakovskiy M.A., Maslenikov V.A. Avtomobil'naya stal' i tonkiy list [Automotive steel and thin sheet]. Cherepovets: “Cherepovets” Publishing House, 2007. 636 p.
Rumyantsev M.I., Zavalishchin A.N., Shapkin P.V. [Similarities and differences in the chemical compositions of steel for the cold-rolled flat product different formability grades]. Modelirovaniye i razvitiye protsessov obrabotki metallov davleniyem [Мetal forming]. Magnitogorsk, Nosov Magnito-gorsk State Technical University, 2014, vol. 20, pp. 200–206 (in Russ.)
Rumyantsev M.I., Zavalishchin A.N., Zavalishchin G.A. et al. [Improvement of the produc-tion of cold-rolled sheet products from steels with a low carbon content in order to increase the con-sumer properties of products]. Proizvodstvo prokata [Rolled Products Manufacturing], 2010, no. 9, pp. 20–27. (in Russ.)
Lutsenko A.N., Rumyantsev M.I., Tulupov O.N., Moller A.B., Novitskiy R.V. Technological re-serves: reasonable implementation of simple solutions to improve hot rolling technology. Vestnik of Nosov Magnitogorsk State Technical University, 2013, no. 5, pp. 70–74.
Idovitov V.A., Trayno A.I., Vol'shonok I.Z., Rusakov A.D.; Trayno A.I., Rusakov A.D. (eds.). Sovremennyye metody povysheniya effektivnosti listoprokatnogo proizvodstva [Modern methods to increase the efficiency of the flat rolled manufacturing]. Moscow, MISIS Publishing House, 2013. 288 p.
Chikishev D.N. Razrabotka i primeneniye metodologii kompleksnogo sovershenstvovaniya tekhnologicheskoy sistemy “Stal'noy tolstyy list – truby bol'shogo diametra” [Development and ap-plication of the methodology to comprehensive improvement of the technological system “Heavy Plate Sheets – Large-diameter Pipes”]. Trudy X kongressa prokatchikov [Proceedings of the Tens Congress Manufacturers of Rolled]. Moscow, “Your format” Publ, 2015, vol. 2, pp. 259–265. (in Russ.)
Kotsar S.L., Belyansky A.D., Mukhin Yu.A. Tekhnologiya listoprokatnogo proizvodstva [Tech-nology of sheet rolling production]. Moscow, Metallurgiya Publ., 1997. 272 p.
Denisov S.V., Zavalishchin A.N., Zlov V.Ye., Potapova Ye.S. [On the possibility of controlling the structure of the hot-rolled strip on broadband mills]. Proizvodstvo prokata [Rolled Products Manu-facturing], 2004, no. 6, pp. 5–8. (in Russ.)
Shkatov V.V. [The influence of the cooling mode on the formation of the uneven properties of hot-rolled strips ]. Vesti vysshikh uchebnykh zavedeniy Chernozem'ya [News of Higher Educational In-stitutions of the Chernozem Region ], 2013, no. 1 (31), pp. 54–58.
Wolanska N., Lis A.K., Lis J. Microstructure investigation of low carbon steel after hot defor-mation. Journal of Achievements in Materials and Manufacturing Engineering, 2007, vol. 20, pp. 291–294.
Paul S., Ahmed U., Megahed G. Effect of Hot Rolling Process on Microstructure and Propeities of Low-Carbon A1-Killed Steels Produced Through TSCR Technology. JMEPEG, 2011, vol. 20, pp. 1163–1170.
Akpan E., Idoko A. Structural Evolution and Properties of Hot Rolled Steel Alloys. Journal of Minerals & Materials Characterization & Engineering, 2012, vol. 11, no. 4, pp. 417–426.
Gareyev A.R., Murikov S.A., Platov S.I. et al. [Directions to improve technology and accelerated cooling equipment on broadband hot rolling mills]. Proizvodstvo prokata [Rolled Products Manufactu-ring], 2015, no. 3, pp. 14–21. (in Russ.)
Zavalishchin G.A. Sovershenstvovaniye proizvodstva kholodnokatanogo listovogo prokata iz staley s ponizhennym soderzhaniyem ugleroda s tsel'yu povysheniya potrebitel'skikh svoystv produktsii: dis. kand. tekhn. nauk [Improving the production of cold-rolled sheet steel with low carbon content in order to improve the application properties of products. Cand. sci. diss.]. Magnitogorsk, Nosov Magni-togorsk State Technical University, 2008. 183 p.
Wolanska N., Lis A.K., Lis J. Microstructure investigation of low carbon steel after hot de-formation. Journal of Achievements in Materials and Manufacturing Engineering, 2007, vol. 20, pp. 291–294.
Gladchenkova Yu.S. Upravleniye strukturoy i svoystvami prokata iz nizkouglerodistykh i nizkolegirovannykh staley dlya polucheniya izdeliy metodami shtampovki: dis. kand. tekhn. nauk [Ac-tions into the structure and properties of rolled low-carbon and low-lying steels to obtain products by stamping methods. Cand. sci. diss.]. Moscow, I.P. Bardin TSNIIchermet, 2016. 158 p.
Shatalov R.L., Genkin A.L. Operating a sheet-rolling complex to minimize energy costs. Metal-lurgist, 2008, vol. 52, no. 9–10, pp. 485–490.
Traino A.I., Garber E.A., Yusupov V.S., Vinogradov V.A. Determination of the formability pa-rameters of IF steel sheet. Intern. forum for the properties and application of IF steels. Forum book. To-kyo, ISIJ, 2003, pp. 427–430.
Nazaybekov A.B., Talmazan V.A., Rumyantsev M.I. et al. [Study of the mechanical properties of cold rolled steel ]. Vestnik Karagandinskogo gosudarstvennogo universiteta [Bulletin of the Karagan-da university], 2016, no. 2, pp. 20–23. (in Russ.)
