In order to avoid frequent unwarned shutdowns of motors, diagnosis and analysis of electromechanical equipment is a very important task. Aiming at a single motor fault in the roller motor, an intelligent motor fault diagnosis and analysis strategy based on deep learning was proposed according to the motor current data collected under normal operating conditions and fault conditions of all motors. Considering the current of other motors working in coordination to diagnose the fault of the monitored motor was proposed for the first time. In this scheme, the Lenet-5 model was used for classification prediction training to diagnose faults of the motor. In addition, the actual deployment and implementation of this program and the collection of experimental data showed that the proposed method was feasible and effective in motor fault diagnosis.

In order to study the relationship between the existence of coke in the hearth and the furnace running state, used in furnace radial sampling technology, through the different large blast furnace hearth area from the coke accumulation degree, graded existence state, its composition and structure and thermal state performance testing and analysis, and statistical out at this stage the blast furnace operation indicators. The correlation law between the existing state of coke in the furnace and the furnace operating index was regression. The analysis results show that the coal injection quantity can be increased by 4.66 kg/t and the fuel consumption can be reduced by 4.77 kg/t for each 1 mm increase of coke particle size in the hearth. At the same time, if a large blast furnace wants to get a better operation effect, the residue and iron retention in the dead material column should be strictly controlled within 45%.This also verifies that in good operation of the blast furnace, in addition to choosing high quality raw fuel into the furnace, in order to reduce the degree of coke melting loss in the furnace, strengthen the function of the material column; in addition, air volume and air pressure should be carried out as the priority adjustment measures to improve the hearth activity.

The S31609 austenitic stainless steel containing residual delta-ferrite was sensitized at 650 ℃ for 2 h. The corrosion characteristics of residual delta-ferrite and austenite grain boundary were analyzed and compared by metallographic etching, electron probe microanalyzer and scanning Kelvin probe. The results show that the residual delta-ferrite is rapidly decomposed into sigma phase, secondary austenite phase (γ₂) and Cr₂₃C₆ during the sensitization process. Although there is no obvious Cr and Mo solute depleted zone at austenite grain boundary and δ/γ grain boundary, the potential difference between the precipitated phase and the adjacent substrate always exists. The Fermi energy of the secondary phase, such as the sigma phase, γ₂ and Cr₂₃C₆is lower than that of the matrix, which makes it easier for electrons to jump from the Fermi surface of the surrounding matrix. As a result, the matrix acts as an anode in the electrochemical corrosion system, and the corrosion occurs preferentially.

Smart manufacturing represents the future development trend of the manufacturing industry. It is the main direction of the implementation manufacturing strong country, and also the key way for the transformation and development of steel industry and building a strong country of steel industry. This paper describes the smart manufacturing of steel enterprises from four aspects, including the principle of smart manufacturing of steel industry, the structure of smart plant of steel industry, the big data of steel manufacturing process, and the trans-value chain remodeling of steel field, and proposes that the purpose of smart manufacturing of steel enterprises is to realize the shaping of value chain among processes, and realize the maximization of value.

Aiming at the problem of high fuel consumption in Ansteel No.4 BF,the ternary basicity is established, and the differential distribution method is adopted for the rational charging, implementing a central oriented and moderately loose edge distribution mode to improve the reduction effect of furnace burden. The lower adjustment focuses on controlling the air flow, adopting a pressure matching mode to operate the blast furnace, and optimizing the calculation of the blast kinetic energy and the area of past tuyere to obtain an appropriate raceway of the swing zone to activate the hearth. At the same time, different measures such as reasonable control of slag skin thickness, soft melting zone form and slag basicity are adopted. On the basis of controlling a reasonable operation of furnace typere, different visualization methods are applied and data platforms are constructed. It strengthens the monitoring of the running state of BF to a great extent and achieves a good effect of increasing daily output by 476 t/d and decreasing fuel consumption by more than 20 kg/t. It also realizes the purpose of increasing production and increasing efficiency of No.4 BF.

The nexus between water and energy in iron and steel enterprise was studied from the view of energy consumption of water usage in iron and steel production. And then the concept of water energy intensity was put forward to evaluate the energysaving level of water resources utilization in the production process of enterprises, and the waterenergy nexus model of iron and steel enterprise was established. Taking a large iron and steel enterprise in China as an example, the relationship between water and energy was calculated and analyzed. The total waterenergy quantity of the enterprise was 55 709 kW·h/h, the energy of the reused water consumption accounted for 82% of the total water energy of the whole steel enterprise, the energy of hydration water accounted for 16%, and the drainage water energy only accounted for 1%. Hot rolling process accounted for the largest proportion of all processes, followed by ironmaking and steelmaking, and cold rolling, sintering and coking processes were the lowest. The waterenergy intensity per ton of steel was 0.208 kW·h/m3, and the waterenergy intensity of the ironmaking process was the highest, followed by hot rolling and steelmaking, and the sintering, cold rolling and coking processes were the lowest. Finally, the direction and measures for energy saving were obtained from the perspective of water resources utilization in iron and steel production.

 Regenerative reheating furnaces for the rolling process are widely used in steel plants because of its energysaving and emissionreducing characteristics. However, negative effects including high furnace hearth pressure and high electricity consumption in fans occur due to its forced flue gas extraction and air supply modes. The regenerator is a key component of the regenerative reheating furnace, and it is important to understand the pressure distribution in the regenerator of the furnace. Differing from the previous cold state experiment and numerical simulation, a semiindustrial experimental setup was established to conduct the hot state experiment, with furnace No.1 of Ansteel continuous rolling sector as the prototype. It was concluded that, under the flue gas extraction condition, the pressure inside regenerator will increase with the increase of flue gas velocity. While, under the air supply condition, the pressure inside regenerator will increase with the increase of furnace hearth temperature. For a given length of a regenerator, the pressure loss of the flue gas extraction process was higher than that of the air supply process. Pressure losses of both flue gas extraction and air supply processes will increase with the increment in the length of the regenerator.

Based on the parameters of actual production conditions, the induction heating process of high strength bulb flat steel was simulated by using the finite element analysis software ABAQUS. The simulation results were basically consistent with the measured results. The influence of coil current density on temperature distribution of bulb flat steel section was investigated, and the optimization scheme of induction heating process parameters for bulb flat steel was put forward. The recommended parameters of the simulation results were that the preheating current density was 7.0×106 A/m3, and the heating current density was 8.5×106 A/m3. Microstructure and mechanical properties of the high strength bulb flat steel before and after optimizing the technological parameters were compared. The results showed that the high strength bulb flat steel produced by the optimized induction heating had better crosssection uniformity.

Open indirect cooling water is the main form of the water system in iron and steel enterprises. It is necessary to study the relationship between water volume and water quality in the process of water supply and consumption for understanding the law of open indirect cooling water system. The concept of "effective water" was put forward by combining water volume and water quality indexes in the process of water use. Mathematical model and related analysis methods were established. A case study of the water supply and consumption in a steel enterprise showed that the change of water quality in both water supply and consumption would lead to the change of water replenishment efficiency of the system, and then the fresh water consumption and wastewater discharge of the system would be changed. Compared with the water quantity index, the concept of "effective water" and its analysis method can more scientifically evaluate the water use characteristics of the open cooling water system.

Regenerative reheating furnaces employing hightemperature air combustion technology are widely applied in the iron and steel industry. Regenerator is the key component of a regenerative reheating furnace, with the switching time as its crucial operational parameter. To discuss the effect of the switching time on the temperature distribution in the regenerator, an experimental regenerator apparatus was established with reheating furnace No.1 of Ansteel continuous rolling sector as the prototype. The experimental apparatus was filled with 10 layers of honeycomb ceramic regenerative units. The effects of the switching time on the temperature profile in the regenerator and the temperature gradient along the regenerator were investigated. Results showed a periodic temperature change of the regenerator. With increasing the switching time, the average temperature of the regenerator first decreased and then increased, while the average temperature gradient along the regenerator first increased and then decreased. The best switching time of the experimental furnace was 70 s, with the corresponding thermal recovery efficiency, temperature efficiency and overall heat transfer coefficient were 81.6%, 91.4 and 18.3 W/(m2·℃), respectively.

The size distribution of coke breeze plays an important role in achieving proper sintering process. Therefore, the effects of size distribution of coke breeze on sinter indices were investigated by means of sintering pot test. Experimental results showed that when the size range of coke breeze used in the sinter pot test increased from "＜1 mm" to "5- 8 mm", almost all of the sintering indices became worse, including tumble strength, productivity, fuel consumption, production yield, sintering rate, and size composition. The size distribution of coke breeze should be adjusted according to the different production strategies. Aimed at sintering with the maximum tumble strength, the size distribution of coke breeze should be 57.20% of "＜1 mm", 25.63% of 1- 3 mm, 11.17% of 3- 5 mm, and 6.00% of 5- 8 mm. When the size distribution of coke breeze was adjusted from the actual used to the optimum, the ore sintering process became reasonable. At the same time, the tumble strength of the sinter was increased 1.48%, the production yield was increased 1.73%, the percentage of size composition between 10 to 40 mm was increased 2.16%, the fuel consumption was decreased 0.69 kg/t and the metallurgical property was improved. The results could provide a scientific guideline on reasonably utilization of fuel resource in actual sinter process.