In the present study, the machinability indices of surface grinding of AISI D2 steel under dry, flood cooling, and minimum quantity lubrication (MQL) conditions are compared. The comparison was confined within three responses, namely, the surface quality, surface temperature, and normal force. For deeper insight, the surface topography of MQL-assisted ground surface was analyzed too. Furthermore, the statistical analysis of variance (ANOVA) was employed to extract the major influencing factors on the above-mentioned responses. Apart from this, the multi-objective optimization by Grey–Taguchi method was performed to suggest the best parameter settings for system-wide optimal performance. The central composite experimental design plan was adopted to orient the inputs wherein the inclusion of MQL flow rate as an input adds addition novelty to this study. The mathematical models were formulated using Response Surface Methodology (RSM). It was found that the developed models are statistically significant, with optimum conditions of depth of cut of 15 µm, table speed of 3 m/min, cutting speed 25 m/min, and MQL flow rate 250 mL/h. It was also found that MQL outperformed the dry as well as wet condition in surface grinding due to its effective penetration ability and improved heat dissipation property.

The latest development trend in rolling industry is the combination of various technological operations in continuous production lines. In the production of long products, the combination of rolling and drawing processes looks promising. A wire drawing mill developed by the team of authors of this work belongs to the conceptually new, integrated lines. The creation of new integrated rolling mills requires a research phase, where relevant concepts are scrutinized using the methods of mathematical modeling. This requires the development of digital (Digital Twin) models that reliably describe the technological processes. It seems efficient to create a Digital Twin for individual units, with their subsequent integration into a complex digital model. This approach was applied in the development of models of electrical systems for the new line. Such models should take into account a wide range of real-life physical relationships. At the same time, a three-high continuous train of stands with an idle inter-stand is the least studied technological unit of the new mill. The absence of an electric drive of the middle stand determines the particulars of deformation processes and the stands’ interconnections through the processed metal. To date, a comprehensive study of such objects has not been carried out. Therefore, the task of studying this technological unit is of immediate interest. The presented publication is devoted to the development of digital models of deformation zones of drive stands and idle stands, as well as of their relationship through the processed metal. The task is solved using the example of an operating pilot production line that implements rolling technology with an idle stand. The authors describe individual Digital Twins and present the structure of the complex model of the studied unit. The most important purpose of the model is to use it in the development of a control method for electric drives of stands to ensure the stability of the rolling process. The developed method should provide a reduction in energy consumption due to the use of friction force reserves present in the idle stand. The authors also substantiate the control principle based on continuous monitoring and alignment of critical angles in the deformation zones of the drive stands. The paper describes a structure of the control system and explains the technical implementation of this principle. The results of mathematical modeling and oscillograms of typical transient processes are presented. The advantages provided by implementing the proposed control method are shown. The work provides an indirect confirmation of the adequacy of the model to the physical object. Recommendations are given on the use of the developed Digital Twin in the study of rolling processes on sheet and sectional mills.

To reduce longitudinal gauge deviations of the head sections at the hot strip mill rolling it is reasonable to profile band of variable thickness due to the length provided by the linear motion of the screw-down arrangements under load. The paper considers the structure of the automatic gauge control system (ACGS) of the indirect type. It estimates the accuracy of screw-down arrangement position control in the single-loop automatic position control system. It also justifies the use of automatic position combined control system. The introduction of the additional channel of control due to the first derivative of the reference input signal was proved to provide the required accuracy values of the strip gauge control. The paper presents data of the pilot study of the developed system at OJSC Magnitogorsk Iron and Steel Works' mill 2,000; they confirm its efficiency.

The manufacture of hot-rolled strips 0.8–1.5 mm in thickness as a final product of metallurgical works necessitates strict requirements for gage interference of the strip, namely, with a tolerance of...

Implementing digital technologies and digital twins (DT) in operating industrial units is one of the key problems in smart production. Metallurgical plants require a solution to implement in the rolling mill retrofitting. A conceptual approach to the virtual configuration of industrial mechatronic complexes based on object-oriented digital twins-prototypes and twins-instances of electromechanical and hydraulic systems is justified. Alternative options for virtual commissioning (VC) were considered, and the Hardware-In-The-Loop (HIL) option was adopted, involving the implementation of DTs in the hardware and software of a programmable logic controller (PLC). Virtual models were built, and control algorithms were tested in the Matlab Simulink software; the prospect of using Simscape domains was noted. The paper’s contribution is the description of a methodology for the development of object-oriented DTs, interlinked in the process, exemplified by a rolling mill coiler. The results of the control over the ‘virtual reeling’ mode are provided; the adequacy of real and virtual processes is confirmed. The problem of developing DTs for a coiler group, solved herein, is a fragment of a large-scale scientific and practical problem of developing DTAs (digital twin aggregates) for interconnected mechatronic rolling mill complexes. The developed VC methodology and proposed DTs are recommended for the commercial implementation in various industrial units. Developing frameworks of mechatronic systems and multi-domain DTE (Digital Twin Environment) applications are shown as prospects for future research.

It was noted that at the manufacturing thin strip at the wide-strip hot-rolling mill stricter requirements to the gauge deviations (uneven gauge) along the strip length are applied. Using the 2,500 mm mill of OJSC Magnitogorsk Iron and Steel Works (OAO MMK) as an example it has been proved that rolling is performed with tensions which exceed several times the accepted values. The main cause is incoordination of speeds of the continuous train electric drives. The developments carried out aim to improve accuracy of setting and controlling loop height in the inter-stand gap. The paper provides the structural diagram of the system of the cascading correction of the stand electric drive speeds. Its distinctive feature is the transmission of the correction signals against the rolling direction. The paper considers the developed system of the strip loop size control effecting speed adjustment for the previous stand of the interstand gap. It substantiates dependencies for calculation of the setting and correction signals. It provides results of the experimental studies of the dynamic modes at the control and disturbance actions. Based on the long-term operation of the developed system at the 2,500 mm mill, its advantages in comparison with the pervious system have been verified. Technical efficiency involves improving accuracy of supporting the set tension and gauge of the rolled strip.