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.

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 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 rectification of audit is the “second half” of audit supervision in state-owned enterprises, the “last kilometer” to realize achievement transformation of audit as well as key link of maintaining the safety of state-owned assets and promoting high quality development of state-owned enterprises. In the paper, the prominent problems of ideological understanding, implementing responsibilities, mechanism construction, supervision collaboration and audit team construction in rectification of audit are analyzed by taking the requirements of closed-loop management system of auditing administration as guidance, combining with the regulations of Rectification and Implementation Measures for Problems Identified in Audit issued by the Audit Office of Inner Mongolia Autonomous Region, basing on the characteristics of large asset scale, multi-level supervision, long business chains and great social responsibilities of state-owned enterprises as well as focusing on their actual situations. Moreover, the optimization strategies are proposed from such five dimensions as implementing responsibilities, perfecting regimes, enabling technologies, establishing collaborative mechanisms and audit team construction, which could provide references for state-owned enterprises to achieve the goal of “rectifying one problem, perfecting one regime and governing one field”.

In the paper, the chemical compositions of BT110V steel for high-strength and high-ductility casing are designed based on the problem that special casing for deep well of oil and gas exploitation is with high strength and low ductility by giving full play to the effects of alloying elements in steel. Moreover, the production process of BT110V high-strength and high-ductility casing is formulated with the existing production equipment of seamless steel pipe. The mechanical properties, hardenability and microstructure of trial-produced BT110V high-strength and high-ductility casing could all meet the technical requirements. For the BT110V high-strength and high-ductility casing with the specification of Φ193.68 mm×10.92 mm, failure strength caused by internal pressure is 58.6% higher than that of the technical requirement, failure strength caused by external pressure is 38.3% higher than that of the technical requirement and joint strength is 26.6% higher than that of the technical requirement. During the process of industrialized promotion and application, all indexes show good stability and the modifying effect of rare earth microalloying on inclusions is obvious.

The edge drop of cold-rolled strip directly affects width accuracy and edge quality of product, it is especially prominent under the conditions of non-oriented silicon steel with wide specification and limited rolling reduction. In the paper, the integrated three-dimensional finite element model coupling with roller-strip steel is established based on the 1 780 mm 6-high CVC (continuously variable crown) rolling mill. Such aspects as geometric modeling, mesh refinement at the edge and contact zone between rollers, boundary constraint, friction contact setting and multi-step load incremental control of this model are optimized. Compared with the measured sectional contour of the unit, the RMSE (root mean square error) of simulation result is 6.85 μm and MAPE (mean absolute percentage error) is 1.26%, which indicate that the model is with higher prediction accuracy. The influences of thickness, width and reduction ratio of strip steel as well as deformation resistance of materials on the formation laws of edge drop are systematically analyzed. The transverse metal flow at the edge could be significantly amplified with the increase of thickness or reduction ratio so as to aggravate edge drop; transverse flow at unit width could be reduced by increasing width of strip steel so as to weaken edge drop to some extent; it is beneficial to inhibiting metal flow at the edge to increase deformation resistance so that edge drop and its sensitivity to reduction ratio are reduced. The simulation system of limited conditions is established based on this to investigate the comprehensive abilities of regulation and control of roll bending forces of working roll and intermediate roll as well as amount of roll shifting for intermediate roll to edge drop. The results showed that the effects of working roll bending on edge drop control were the most significant, the average control effect was approximately 3.5 times of that of intermediate roll bending and about 30 μm of linear regulation amplitude could be achieved for intermediate roll shifting at its positive and negative limiting positions. The efficiency and sensibility of different control methods are with quantitative evaluation by introducing the efficacy coefficients of edge drop control, which could provide the theoretical basis and engineering references for optimization design of roll shape for 6-high CVC rolling mills and formulating the process of edge drop control for silicon steel with wide specification.

For the production line of comprehensive utilization of oxidized ore resources in Bayan Obo, iron and rare earth separations are carried out after two-stage closed-circuit grinding of raw ore as well as fluorite separation is carried out when rare earth tailings are ground to the proportion of particle size<30 μm is over 70%. The multistage grinding causes significant increase of mechanical secondary slime as well as electrostatic repulsion between fine slime particles is strengthened so as to inhibit sedimentation when circulating wastewater is with alkalescence by adding a large amount of sodium silicate and foaming agent during beneficiation process, the silica sol generated by sodium silicate is absorbed on the surface of fine slime particles so as to form coating layer. As a result, the hydrophobic property of particle surface is reduced and affinity of it and water is enhanced so that fine slime particles are more dispersed and stable as well as the content of suspended solids (SS) in water reaches over 5 000 mg/L. The beneficiation wastewater is treated with the process of magnetic coagulating sedimentation-stirring-flocculation-stirring as well as the content of SS in wastewater is reduced to 69 mg/L and pH value is basically unchanged. The flotation test is carried out for circulating wastewater after treatment, it is better for circulating wastewater after treatment to improve the grade and metal recovery rate of iron, rare earth and fluorite than those for circulating wastewater without treatment as well as the dosage of reagents in every link is significantly reduced.

The slow-speed actuating device is changed from built-in brake motor to external hydraulic brake so that the burning loss of motor is effectively eliminated, operation stability of equipment is improved and repair time is significantly reduced aiming at such problems as low operation reliability, short service life of key components and leakage of discharged ore for ball mill in grinding process of baiyuneboite; the protection plate of liner plate for shell and end cover are optimized separately with the composite material of lipid complex rubber and plastic and wear resistant rubber so that their service life is increased to over 2 years as well as long lasting and reliable protection of main body of equipment is realized; the structure is improved and wear resistance is optimized for drum screen at the end of discharging ore so that its service life is increased to over 6 months, replacement of sieve mesh and reuse of framework are realized as well as the problem of damage for flow passage component of slurry pump caused by leakage of steel ball is successfully solved. The practices show that the above improvement measures are with significant engineering application values for ensuring safe production and improving overall production efficiency of mine.

After large proportion of wet quenched coke is added into the large blast furnace of Baotou Steel, there is fluctuation of blast furnace conditions, yield is reduced by 16.26% and coke ratio is increased by 7.23%. The changes of coke quality, metallurgical performances of sinter, load of harmful elements in blast furnace and corresponding changes of blast furnace conditions are analyzed, which could provide references for smelting of adding large proportion of wet quenched coke into large blast furnaces next.

Under the background of increasing competition as well as transformation and upgrading for global manufacturing industry, deeply integrated intensive production and standardized manufacturing have become the key path for improving industrial competitiveness. In this paper, it is systematically explored the theoretical framework, methodology and application practices for integrating innovation of intensive production and standardized manufacturing, which mainly include their core connotation and theoretical foundation as well as establish integrating innovation method system; the challenges, solving strategies and comprehensive benefits in application process of this innovation method are deeply analyzed with the empirical analysis method by taking a group company of Chinese steel industry as the case. The study results showed that the production period and operating costs could be significantly reduced as well as stability of product quality and utilization efficiency of resources could be improved by cooperation of intensification and standardization. Finally, the future development trend of this mode under the background of intelligent manufacturing is expected in order to provide theoretical and practical references for high-quality development of manufacturing industry in our country.