In this paper, such aspects as microstructure, hardness and wear resistance of rare earth wear resistant steel plate BTNM450 of Baotou Steel and NM1^# wear resistant steel plate produced by a foreign manufacturer are selected to be compared and analyzed. The study results showed that the wear extent of rare earth wear resistant steel plate BTNM450 of Baotou Steel was 0.390 0 g, which was significantly fewer than that of NM1^# wear resistant steel plate. Compared with the wear resistant steel plate BTNM450-NORE without adding rare earth elements, the wear extent of rare earth wear resistant steel plate BTNM 450 of Baotou Steel after adding rare earth elements is reduced by 20.9%. The hardness distribution on section of NM1^# wear resistant steel plate is not uniform and hardness of rare earth wear resistant steel plate BTNM450 of Baotou Steel does not change significantly along the direction of section thickness, which is with excellent wear resistance.

In this article, the stability of old underground space in Sanheming Iron Mine is analyzed with the FLAC^3D numerical simulation software as well as distribution laws of stress, displacement and plastic zone of old space with effects of self weight stress field are studied. It is aimed at judging whether old space is stable to analyze the stability of old space with effects of its self weight stress field in order to provide effective preventive measures for managing old space of mine as well as ensure safe and efficient mining of mineral resources. The stability of old space with effects of self weight stress field is considered to be good through 3D modeling and numerical calculations. The study results can provide references for stability analysis of underground goaf in similar iron mines, which is with certain guiding role in ensuring safe production and reducing geological disaster risks as well as significances to promote sustainable development of mineral resources of Sanheming Iron Mine.

In the paper, the theoretical inter-hole delay time and theoretical delay time between rows for such three types of lithology as iron ore, dolomite and slate in firing network are calculated by averaging as well as reasonable parameters are formulated to organize and launch bursting test through analyzing domestic and foreign rock breaking theory of millisecond blasting. The study showed that the reasonable inter-hole delay time of dolomite was 32 ms and that with blast block≤800 mm accounted for 98.17%; reasonable inter-hole delay time of slate was 40 ms and that with blast block≤800 mm accounted for 91.11%; reasonable inter-hole delay time of iron ore was 28 ms and that with blast block≤600 mm accounted for 82.16%. The proportions of qualified block corresponding to reasonable delay time of each lithology are increased.

In this paper, it is introduced the development process and achievements of beneficiation technology study of baiyuneboite. The study and application situations of beneficiation technology of baiyuneboite are introduced from such three stages as focusing on iron, paying equal attention to iron and rare earth as well as comprehensive utilization of resources. Moreover, it is summarized the methods for improving grade and recovery rate of iron concentrate, current situations of beneficiation of rare earth oxide, achievements of beneficiation of fluorite as well as breakthrough of beneficiation technology of niobium mineral.

In this paper, the research is carried out from such aspects as chemical composition, size composition, basic sintering characteristics and process parameters adjustment after production applications of Mongolian powder ore. The research results showed that the air permeability of sinter bed became worse, utilization coefficient was decreased by 0.001 t/ (m²·h), solid fuel consumption was increased by 0.83 kg/t, drum strength was decreased by 0.63 percentage point, average particle size was decreased by 0.05 mm, proportion of particle size of 5~10 mm in finished sinter was decreased by 0.12 percentage point and direct material cost was decreased by CNY 8.15 Yuan/ t when 7% Mongolian powder ore was used to replace the same proportion of Mac powder ore. The sintering process could maintain stable state by increasing moisture of mixture by 0.1 percentage point and fuel proportion by 0.2 percentage point.

In order to explore the effects of adding Indian powder ore on the production efficiency and quality of sinter, the experimental studies on basic sintering characteristics and sinter pot of Indian powder ore are carried out respectively. In the experiment, the current iron charge configuration of 2^# Sintering Workshop of Iron-making Plant is taken as the datum point as well as the Mongolian powder ore and high-silicon Brazilian coarse powder ore are replaced by Indian powder ore respectively. The performances of Indian powder ore are comprehensively evaluated from such aspects as the chemical composition, size composition and quality index of sinter, which provide the basis for determining appropriate adding proportion.

In the energy consumption of sintering process, solid fuel (powdered coke and anthracite) consumption accounts for 70%~80%, so it is the key to reduce solid fuel consumption for reducing energy consumption of sintering process. In the paper, it is introduced the air leakage rate of sintering machine is decreased to 35% and effective height of sinter bed is increased to 780 mm through such measures as equipment transformation, optimizing technological operations and strengthening production management combining with the existing conditions of raw materials and fuels aiming at the problem of higher solid fuel consumption for 265 m² sintering machine of Baotou Steel; proportion of size fraction of outsourced powdered coke <1 mm for sintering is decreased from 41.02% to 22.72% through revising the purchase standard of outsourced fuels for sintering so that size composition of fuel for sintering is improved. The solid fuel consumption for 265 m² sintering machine of Baotou Steel was reduced to 50.75 kg/t in 2023 through the above measures, which was 1.70 kg/t lower than that in 2021.

In the paper, the blast furnace smelting with large proportion of pellets is summarized as well as the effects of such processes as pelletizing, sintering and blast furnace on energy conservation and emission reduction of steel productions are quantificationally analyzed combining with actual production situations. The results showed that the carbon emission, energy consumption and pollutant discharge amount per ton of steel could be reduced by increasing the proportion of pellets and reducing the proportion of sinter in blast furnace. The study could be as reference for energy conservation and carbon emission reduction in the iron and steel enterprises with blast furnace-converter production process.

Such parameters as the outlet temperatures of crystallizer and secondary cooling section and shell thickness of manufacturing 2 types of rectangular billet with cross-section dimensions of 280 mm×380 mm and 320 mm×415 mm are simulated through high temperature thermal simulation experiments and computer software as well as the production process parameters of manufacturing YQ450NQR1 weathering steel with the billets of 2 different cross sections are compared. The results showed that the low magnification quality of billet was related to amplitude of crystallizer, amount of secondary cooling water, number of strands for continuous casting machine and temperature of exiting secondary cooling section while entering tension leveler. With the decrease of amplitude of crystallizer, increase of number of strands for continuous casting machine and temperature of entering tension leveler, the quality of billet is improved. When the amplitude of crystallizer is ±2.5 mm and temperature of entering tension leveler is greater than 940 ℃ with the condition of weak cold secondary cooling water, the low magnification quality of billet with cross section of 280 mm×380 mm of peritectic weathering steel is better than that of billet with cross section of 320 mm×415 mm.

The hot rolled coil plate for pipeline steel is mainly used for manufacturing delivery welded pipe of petroleum and natural gas. In this paper, the development of hot rolled coil plate for L485M pipeline steel with heavy gauge and low costs is introduced. The design with diversified alloy systems of C-Mn-Cr-Mo or C-Mn-Cr-Mo-Ni as well as smelting of clean steel and thermo mechanical control process (TMCP) are adopted. The microstructure of developed L485M hot rolled coil plate is acicular ferrite+granular bainite and precipitate is homogeneous. The L485M hot rolled coil plate is with such characteristics as high strength and excellent low temperature toughness through such mechanisms as dislocation strengthening and precipitation strengthening. The experimental results showed that the L485M hot rolled coil plates with and without Ni element could meet the technical requirements as well as was with capacity of batch production, which is beneficial for enterprises to reduce costs and increase benefits.

As one of key materials in the new energy automobile industry, non-oriented silicon steel for driving motor of new energy automobile is with broad application prospects and huge market potential. In this paper, it is discussed the performance indexes of non-oriented silicon steel for driving motor of new energy automobile as well as briefly summarized current research status of non-oriented silicon steel on such aspects as rare earth modification, optimization of annealing process and practical applications of motor. The overall performances of non-oriented silicon steel for driving motor of new energy automobile could be significantly improved by adding rare earth elements into non-oriented silicon steel, continuously optimizing annealing treatment process and making targeted improvements combining with the requirements of practical applications of motor.

The test steels with different La contents are smelted in vacuum induction furnace under laboratory conditions. The morphology and size of inclusions are studied with X-ray diffractometer, field emission scanning electron microscopy, Bruker energy spectrometer, OTS software and electron probe micro-analyzer (EPMA). The results showed that the inclusions, AlN and Al₂O₃ are modified into La-O-S, La-O-S-Al and LaS as well as inclusion size was decreased from 4.37 μm to 2.92 μm by adding La into X100 pipeline steel. The refinement effect of La on austenite grain size is obvious. With the increase of La content, austenite grain size in test steel is increased from level 5 to level 8.5. After adding rare earth La, the main inclusions in steel are La-O-S and La-O-S-Al of about 2 μm in size with the pinning effect so that austenite grain size is reduced significantly.

In the paper, it is introduced the Charpy pendulum impact test and drop weight tear test (DWTT) of L360M pipeline steel coil plate with the thickness specification of 11.00 mm. The test results showed that the differences of toughness at relevant positions of the same plate are smaller. It can be seen from the macroscopic morphology of fracture of samples for DWTT that the bigger the deflection of samples, the more obvious the distortion of samples for fracture after hammering to breakage, even some samples could not be hammered to breakage completely because of warping.

In this paper, the continuous cooling transformation (CCT) behavior of undercooled austenite and hardenability at different quenching temperatures of 770 MPa grade steel for crane boom are systematically studied. The critical transformation points of test steel are determined and evolution rules of metallographic structure for test steel at different cooling speeds are analyzed through thermal simulation test. The results showed that complete martensitic structure could be obtained when cooling speed reached above 30 ℃/s. The depth of hardening layer corresponding to 50% of martensitic structure content was 30 mm when hot quenching was at 920 ℃, which showed that test steel was with good hardenability.

In this article, the low temperature performances of 60 kg/m as-hot-rolled U71Mn and U75V rails as well as U71MnH and U75VH rails after on-line heat treatment produced by Baotou Steel are studied. The relation between the toughness and temperature of different rails in low temperature environment is studied through impact test and test for fracture toughness of rails in the low temperature environment created in the laboratory. It is elaborated the performance indexes of safe service for rails of Baotou Steel in low temperature environment and summarized the relations of toughness indexes for four types of rail products of Baotou Steel in low temperature environment, which provide the data support for selecting rails in plateau and low temperature regions as well as safe operations of railway system in extremely cold environment.

With the increasing development and utilization of marine resources, corrosion of structural materials of marine engineering is facing severe challenges. In this article, it is summarized the research progress on corrosion status of steel in marine environment as well as deeply analyzed such influencing mechanisms as marine atmosphere, splash zone of seawater, tidal and splash zone as well as immersion zone of seawater on corrosion behavior of steel. The main current technical measures to retard corrosion of steel in marine environment are summarized as well as development direction and application prospect in future marine engineering of new corrosion-resistant steel are discussed by discussing the effects of such environmental factors as dissolved oxygen, salinity, temperature, pH value and microorganism on corrosion rate of steel aiming to provide the technical support for improving corrosion resistance of structural materials of marine engineering.

In this paper, the effects of different quenched-tempered heat treatment processes on the microstructure and mechanical properties of 30CrMoA round steel for sucker rod are studied. The strength and toughness of the material are improved by adjusting the quenching and tempering temperatures as well as optimizing heat treatment process aiming at the actual application requirements of 30CrMoA steel. The experimental results showed that the yield strength, tensile strength, yield ratio and impact energy of the material could be significantly improved with proper quenching and tempering, especially under the conditions of 850 ℃ quenching(water cooling) +540 ℃ tempering (water cooling), the comprehensive mechanical properties of round steel 30CrMoA for sucker rod were the best, which was with good strength and toughness. The metallographic analysis showed that the quenched and tempered microstructure was mainly composed of tempered sorbite, which was with stable microstructure.

There are such situations as wear and track gauge that is out of tolerance as well as such accidents as offtrack of travelling wheel for coke guide and fracture of track in the process of production and operation more than once due to overage service of the track for coke guide of 6 m coke oven of Coal Coking Chemical Industry Branch Co. so that the coke oven stops production frequently. The size of track is determined to be with the height of 1 61 0_{-2}^{+3} mm and center distance of 2 70 0_{-2}^{+2} mm by taking starting points of the tracks at the ends of coke guide as reference as well as combining with the surveying and mapping values of track through on-site measurement and survey. For the construction, old track is completely replaced without stopping production by using the thermit welding method of track joints so that on-site production requirements could be met. This method could be popularized to the replacement of tracks for coke guide in coking industry.

In the detection of building foundation piles, crosshole sonic logging is the important detection method to judge the integrality of pile body for cast-in-place concrete pile. In this paper, it is introduced the basic principle and judgment basis of detecting integrality of pile body with crosshole sonic logging as well as summarized the process flow and matters needing attention of on-site detection by taking the project of archives center in a city as an example, which provide accurate detection data for the quality of foundation pile in project.

The status survey and heat loss test of steam pipeline network system of Baotou Steel are carried out as well as its amount and rate of heat loss during heating season in the winter are calculated aiming at its existing problem of great heat loss. The energy saving transformation measures to reduce heat loss of steam pipeline network system are put forward by analyzing current influencing factors of greater heat loss for the system, which could provide the reference for transforming steam pipeline network system of Baotou Steel.

It is helpful for better energy management and optimization as well as realization of sustainable development of enterprises to improve the accuracy of energy measurement. The accuracy rate of data acquisition could be improved by strengthening energy measurement management, perfecting relevant management systems, selecting reasonable sampling points and acquisition and calculation modes as well as using means of data analysis so that the facticity, reliability and fairness of energy data could be guaranteed, which could provide strong supports for such aspects as energy conservation and emission reduction, cost accounting and quality control of enterprise.

The management of receivables and payables is an important part of financial management in enterprise. If it is not in place, it will affect the capital chain of enterprise and then impact normal operations of enterprise. Therefore, the management of receivables and payables in enterprise should be strengthened as well as risk control of receivables and payables should be paid more attention to. In the article, it is expounded the necessities of management of receivables and payables as well as analyzed the management and risk control of receivables and payables with the SWOT model to reveal their internal strengths, weaknesses, opportunities and threats they are facing by taking a research institute as an example, which could provide the reference for formulating effective management strategies and risk prevention measures.