The development idea of green and low-carbon smelting technology is actively practiced in Baotou Steel by taking the principle of “high efficiency, low consumption and high quality”. In recent years, with the increase of proportion of self-produced ore, gas utilization rate of the whole plant is increased by 2.43 percentage points, fuel ratio is cumulatively reduced by 33.1 kg/t and utilization factor of blast furnace is increased by 0.132 t/(m³·d) through actively improving quality of raw materials and fuel, controlling contents of harmful elements as fired, high oxygen enrichment, high blast temperature and coal ratio, selecting suitable theoretical combustion temperature, optimizing charging system, refining basic management of stokehole and standardized operations of production equipment as well as strengthening collaborative guarantee of working procedures. As a result, all technical and economic indicators are with greater progress.

In order to evaluate the welding fatigue performance of plate with high strength wind power steel Q420NE, the plate with the thickness of 20 mm is welded with submerged arc welding process, fatigue trend diagram (S-N curve) of welded joint is obtained through fatigue test and fatigue limit under set condition is calculated based on this. When repetitive loading is set to be 10⁷ times, the maximum measured fatigue stress of welded joint is approximately 300 MPa, corresponding stress amplitude is 150 MPa and survival rate is 50%; when survival rate is 97.7%, its maximum fatigue stress is approximately 284 MPa and corresponding stress amplitude is 142 MPa.

The disease characteristics are accurately studied and judged through refined detection on site aiming at such composite diseases as sedimentation, leakage and structural aging that have become prominent during the operations of closed conduit for diversion closed conduit of Baotou Steel for over 65 years. The systematic comprehensive treatment scheme is established by adopting the collaborative dredging technology of “horizontal directional drilling machine+ dredging vehicle with high-pressure water jet” and graded leaking stoppage technology of composite grouting as well as combining with the full-process closed-loop construction monitoring system. The water transfer function of closed conduit is fully recovered, conveyance capacity is increased from 30% before treatment to 5 m³/s, the designed flow rate of water transfer and service life of structure is extended by over 15 years after implementing this scheme, which provides the reproducible and propagable technological paradigm for treating aged water conservancy facilities in the Yellow River basin.

The study on composition design of Nb microalloying and process optimization for HC300LAD+Z high strength low alloy steel is carried out based on the 1 880 mm hot-dip galvanizing production line of Baotou Steel in order to meet the market requirements of 300 MPa grade high strength galvanized sheet for light weight of home appliances. The effects of soaking temperature for hot-dip galvannealing process (790~850 ℃) on mechanical properties of product are systematically studied through the thermal simulation test and industrial trial production. The results showed that the increase of soaking temperature caused grain coarsening, yield strength was decreased from 335 MPa at 790 ℃ to 297 MPa at 850 ℃ and elongation was increased from 28% at 790 ℃ to 38% at 850 ℃. The target soaking temperature of annealing for industrial production is controlled at 810±15 ℃, microstructure is equally distributed ferrite+ a small quantity of pearlite without mixed crystal, yield strength is 310~368 MPa and elongation is 28%~39% for product, which could meet the thickness reduction requirement of 20% for components of home appliances so that the solution of reliable material for light weight of steel for home appliances is provided. The influencing mechanisms of annealing temperature on recrystallization behavior of Nb microalloyed steel are revealed in this study, which could provide the practical references for optimizing production process of high strength low alloy steel with similar production lines.

The construction industry is currently undergoing digital transformational changes. The traditional construction engineering management model is faced with such pain points as extensive management and control, low efficiency and insufficient collaboration, which is difficult to adapt to the demands of high-quality development. The intelligent construction technology is promoted to become the core driving force of engineering management innovation by issuing the Guidelines of Intelligent Construction Technology (Trial). In this paper, the core connotation of intelligent construction technology and transformation needs of construction engineering management are sorted out, internal logics of their integration are explored, innovative application paths of intelligent construction technology in engineering cost, schedule, quality and safety control are focused on, implementation guarantee system of technology applications is constructed as well as the demonstration is supplemented combining with relevant technical principles and industrial construction application scenarios by adopting the methods of literature research and theoretical analysis. The research showed that the digitization, refinement and intelligent upgrade of engineering management could be realized, bottlenecks of traditional management could be broken as well as efficiency and quality of engineering management could be improved with the intelligent construction technology.

The high carbon medium manganese steel is with the La+Ce complex processing. The occurrence state and change rules of storage for La and Ce in high carbon medium manganese steel as well as the effects of La and Ce on sulfides, oxide inclusions, microstructure, static compression hardening efficiency and impact wear property are systematically studied through the composition analysis, microstructure observation, 30% static compression, impact wear test and theoretical analysis. The study results showed that the contents of solid solution La and Ce in steel could not be increased by adding into a large amount of La and Ce as well as they all remained below 0.003 5% for high carbon medium manganese steel. The 30% static compression hardening efficiency at room temperature can be improved with La and Ce, from 94.4% without La and Ce to 96.68%~108.2% with La and Ce; impact wear resistance of sample is improved with La and Ce as well as relative wear resistance is increased by 1.057 0~1.606 9 times when impact load is 2 J and 1.080 4~1.374 1 times when impact load is 5 J. Under the experimental conditions, the optimal amount of La+Ce added into high carbon medium manganese steel is 0.20%~0.25%.

In order to solve the problem that the dispersed degree of detection results for residual carbon in incoming inspections of diesel oil is high, the effects of constant weight operation on inspection data stabilization are explored by selecting such four key indexes as residual carbon, ash content, total pollutants and mechanical impurities with the control variate method in this study. The results showed that there were no obvious differences for the stabilization of two groups of data due to the mandatory constant weight in standard of detection of ash content; the relative standard deviations of detection results for residual carbon, total pollutants and mechanical impurities were increased to 5.3%, 8.7% and 7.9% respectively as well as dispersed degree of data was significantly increased without constant weight operation. In the detection of residual carbon for diesel oil, the uncertainty of weighing could be effectively reduced and system errors could be controlled by supplementing constant weight operation of empty sample tube so that the accuracy and repeatability of detection data in such situations as low residual carbon (≤0.1%) samples and proficiency testing could be improved. This study provides the references for quality control of detecting diesel oil in laboratory.

As the key node of urban gas transmission and distribution system, safe and stable operations of gas station are highly dependent on continuous and high-quality electric energy supply. In this paper, the systematic research is carried out combining with the reliability theory and energy storage technologies of electrical power system aiming at the vulnerability of power supply system for key equipment in gas station (take the city gas gate station and LNG peak-shaving station as examples). Firstly, identify such key sensitive loads as compressor, electric drive pressure regulating device, safety instrumented system (SIS) and process control system (PCS) based on the architecture of power supply and distribution system as well as load characteristics in typical gas station; secondly, the influence probability and severity of consequences of such accidents as external power grid failures, internal electrical failures and voltage sag on key loads are with quantitative analysis by establishing vulnerability evaluation model of power supply system combining with the probabilistic risk assessment (PRA) and sequential Monte Carlo simulation; finally, the enhancement strategies taking energy storage system (including but not limited to UPS, flywheel energy storage, super capacitor and hybrid energy storage) as the core are proposed, optimum collocation model of energy storage capacity with the targets of power supply reliability, power quality improvement and full life cycle economy is established as well as emulation proof is carried out with the platforms of ETAP and MATLAB/Simulink.

The research object of this paper is the light carriage of electric wheel mining dump vehicle with load of 330 t. The three-dimension design of light carriage is carried out with Pro-E software, the simplified three-dimensional model is introduced into ANSYS for finite element analysis. The structural safety of carriage under the two typical working conditions of being fully loaded and stationary as well as driving on uneven road is analyzed based on the actual operations of electric wheel mining vehicle. The analysis results showed that the overall stress distribution of light carriage was more uniform, safety factor was larger, while deformation was relatively smaller as well as its strength and stiffness could meet the use requirements.

This paper is aimed to discuss the strategies for coal machine enterprises to manufacture middle trough of scraper conveyor with intelligent welding equipment. The applications of intelligent welding technologies in production of middle trough for scraper conveyor are comprehensively studied, which include the design of welded structure and process optimization as well as real-time monitoring integrated with multiple sensors. The comprehensive applications of multiple technologies could significantly improve the welding operation efficiency and welding quality of middle trough. It is expected that the content of this research could provide intelligent solutions as references for manufacturing enterprises of coal machine and mining production units.