The choice of the chemical composition of new sparingly alloyed high-strength cold-resistant steels with strength level of at least 950 MPa for heavily loaded equipment is substantiated. Thermokinetic diagrams of decomposition of supercooled austenite are plotted for the steels with selected chemical compositions. Heat treatment modes are suggested. The mechanical properties during the heat treatment are determined to develop recommendations for the use of the research results under industrial conditions.
The properties of deposits in equipment within the machine department (the gas injection machine) and the pipeline delivering coke oven gas are studied, and the process by which they are formed is considered. As an example, attention focuses on the shop for capture and processing of coking products at Magnitogorsk Iron and Steel Works (PAO MMK), which uses various technologies for the cooling and cleaning of coke oven gas.
This report reviews an example of acoustic positioning of partial discharges (PD) in the tank of a high-voltage oil-filled transformer. The literature review confirms the importance of PD monitoring and justifies the feasibility of positioning discharge activity centers. The precise positioning of PD sources is required to determine the location of insulation defects. The authors provide brief information on the development of PD positioning methods and note that their practical application has been insufficiently covered in publications. They present the results of electromagnetic and acoustic PD positioning in a 110 kV transformer. Some details are provided on the devices and measurement methods used, including the localization of areas with increased PD intensity using one acoustic sensor and the subsequent center localization through the installation of 4 sensors at even intervals. The authors provide PD signals and defect impulses received from each of the sensors and demonstrate the difference in the registration time of these signals. They explain the principle behind PD center positioning, which is determined considering delays in signal reception. The authors demonstrate the usage of the Inva (Portable) software for the processing and visualization of acoustic positioning results. They note that changes in the propagation rate of acoustic waves in a heterogeneous medium result in the reduced accuracy of results. The authors also outline the prospects of the research into the elimination of occurring defects.
Technological aspects of creating a new brand of high-strength steel in the modern industrial conditions of the Magnitogorsk Iron and Steel Works are considered.
The development of digital twins (DTs) of industrial electrical systems is attributed to the need for the reduction of time and material resource inputs during their virtual commissioning (VC). The same problem occurs during renovation with complete or partial equipment replacement and/or control systems. These problems can be efficiently solved by developing object-oriented DTs based on the Simulink Real Time software and using hardware-in-the-loop simulation (HIL). This software is compatible with Matlab Simulink and the Simscape package, which makes it suitable for the industrial usage. The authors suggest a HIL-based approach that helps make a virtual real-time computer model, with process control signals coming from the industrial PLC that controls the real physical object. This problem occurred during the renovation of the horizontal stand electric drives of a 5000 plate mill. The authors provide the flow charts of the electromechanical system and the object-oriented DT. The implementation of DT in Matlab Simulink Desktop Real Time is reviewed in laboratory settings. The authors present the block structures that make up a virtual model of the electromechanical system. The developed DT was used to adjust control algorithms and controllers and study the dynamic modes over a rolling cycle. The adequacy of the processes was tested by comparing the oscillograms obtained with the developed DT and the rolling mill. The authors stress the feasibility of developing DTs on the Simulink Real Time platform using HIL simulation during VC and renovation of complex industrial objects.
