The stamping simulation workstation for sheet products of Baotou Steel is the typical research platform of applied technologies. With the coordinated supports of “numerical simulation and finite element simulation” technologies, it relies on multiple high performance personal computers to complete massively parallel computation so that the joint interactions of such four main fields as “stamping simulation analysis” “construction of material database” “correlational research of surface” and “comprehensive simulation” are realized. A large amount of simulation analysis is carried out on the platform, which not only provides the basis for optimizing and adjusting the processes and performances of sheet products, but also contributes to winning market reputations for high-end products such as automotive sheet of Baotou Steel. At the same time, the construction of material database promotes the substantial progress of early vendor involvement (EVI).

In order to eliminate the hidden dangers of rock falling and slope slide on slopes in Main Stope and East Stope of Bayan Obo Iron Mine as well as improve slope stability, the stability analysis of the slopes in Main Stope and East Stope of Bayan Obo Iron Mine is carried out. Such modes of slope treatment as full-length grouted bolt+shotcrete with wire mesh on slope surface+drainage opening, drainage with drainage opening and pre-stressed anchor cable+reinforced concrete retaining wall+rib column+drainage opening and pre-stressed anchor cable+half lattice girder+shotcrete with wire mesh+drainage opening are taken to reinforce the sectors with rock falling or slope slide in Main Stope and East Stope of Bayan Obo Iron Mine. Moreover, such slope monitoring systems as artificial monitoring, total station monitoring, slope radar, fracture meter and global navigation satellite systems (GNSS) receiver as well as corresponding safety management system are established to ensure the slope stability and safe productions of the mine.

In this paper, it is systematically introduced the characteristics of impurity distribution for slurry pipeline and effects of pigging with different types of tube cleaner by taking the pigging and descaling for a long distance high pressure slurry pipeline of iron ore concentrate with variable diameters as an example. It is found through actual pigging that the passability of pipeline could be preliminarily detected with soft foam pig and mechanical tube cleaner with leather cups of different shore hardnesses. In addition, the effect of cleaning scale for slurry pipeline with foam pig is poorer, so the mechanical tube cleaner with stronger pigging ability should be preferred, which is with important guiding significance for pigging of similar slurry pipelines in the future.

In the paper, the current situation of higher solid fuel consumption for 2^# sintering machine in 2^# Sintering Workshop of Iron-making Plant of Baotou Steel is systematacially analyzed. The fuel with comprehensive particle size>5 mm is controlled at 15%~20% and that with comprehensive particle size<1 mm is controlled at about 30% through classifying different fuel bands, putting them into tank and crushing them as well as controlling reasonable proportion of anthracite and coke powder; effective material layer thickness is increased and automatic heat storage effect is improved through increasing height of baffle for trolley of sintering machine to 750 mm and reducing thickness of bed charge from 85 mm to 70 mm; overdamp layer of sintering is reduced through reducing moisture of sinter mixture from 7.2% to 6.9%. The solid fuel consumption in 2^# sintering workshop is reduced significantly through taking the above measures. It reached 50.33 kg/t in 2023, which is 2.13 kg/t lower than that in 2021, which lays the foundation for further reducing energy consumption in working procedure before iron-making.

In this paper, it is analyzed the causes of abnormal temperature increase of side wall at tap hole for hearth of 7^# blast furnace of Baotou Steel and emphasized the treatment measures. With the long-term high-intensity smelting conditions, tap hole of hearth is relatively active and its length is controlled poorly so that scour of slag iron to carbon brick of tap hole is aggravated. As a result, the erosion of carbon brick of tap hole is the cause for temperature increase of side wall at tap hole for hearth of 7^# blast furnace. The temperature of side wall at tap hole is effectively controlled without reducing the smelting intensity and output of 7^# blast furnace through taking such measures as increasing the quantity of circulating water at tap hole to improve cooling intensity, carefully maintaining tap hole, actively eliminating air gap of hearth side wall as well as appropriately opening central gas stream and restraining gas stream at edge for the charging system.

The industrial production process of rare earth steel involves the problem of yield of rare earth and stable yield is the important guarantee for stable performances of rare earth steel products. The effects of addition of position, addition amount and composition of liquid steel (oxygen activity, sulfur content) on yield of rare earth for rare earth steel are studied by adding rare earth in ladle and sampling analysis of tundish. The results showed that the yield of rare earth was increased in turn by adding rare earth in ladle, tundish and crystallizer; the larger the addition amount of rare earth alloy before off-position of ladle furnace, the lower the yield; the higher the contents of oxygen and sulfur in liquid steel, the lower the yield of rare earth.

There is often flocculent flow at nozzle during casting rare earth steel products with continuous casting machine so that the casting with normal casting speed could not be met. In severe case, the flocculation at tundish nozzle causes interruption of production so that continuous casting production is seriously affected. The steelmaking technologies of rare earth steel are optimized by studying the reaction mechanisms after adding rare earth elements into molten steel as well as analyzing the effects of oxygen content of molten steel, oxidizability of slag, protective casting of continuous casting machine and casting temperature on yield of rare earth Ce. As a result, the yield and castability of rare earth elements in molten steel are improved as well as the number of continuous casting heats for rare earth steel products reaches 25 so that scale production of rare earth steel products is ultimately achieved.

Such effective measures as adopting optimum parameters of power transmission, forming refining white slag with microfoam as early as possible, optimizing modes of bottom blowing, accurate temperature control as well as optimizing dust removal control and electrode wrench are taken through experiments of multiple heats aiming at such phenomena as oxidation, melting loss, thermal vibration and drop out of electrode easily occurred during the heating process of ladle furnace. As a result, the consumption of electrode for ladle furnace is decreased from 0.544 kg/t in 2021 to current 0.347 kg/t so that stable and trouble-free operations of smelting for ladle furnace is ensured as well as cost decreasing and benefit increasing and high efficiency continuous casting are achieved.

The locations of disqualification of flaw detection for defects are accurately positioned through manual flaw detection of Q355NE plates with disqualification of online flaw detection as well as the microstructure and defects of the locations of disqualification of flaw detection are analyzed with optical microscope and electron microscope. The results showed that the defect corresponding to disqualification of flaw detection for Q355NE wind power steel was the microcrack in the center of steel plate, microstructure of the microcrack area in the center was martensite and bainite with poorer plasticity, which was caused by segregation of C and Mn. At the same time, MnS inclusions with long strip shape as well as compound of titanium and niobium distributed in chain are found at the crack. The interfacial bonding energy of them and matrix is low, continuity of matrix is destroyed so that cracks are easily initiated with the effects of stress. The microcracks in the center are avoided and qualification rate of flaw detection for wind power steel is increased by improving the segregation during solidification process of casting blank and adopting the mode of offline slow cooling of steel plate.

There is cracking failure at the weld seam of high strength and toughness 490CL wheel steel rim made with flash butt welding during flaring and forming process. Its causes are analyzed through macroscopic and microscopic observations of fracture morphology, tests of chemical compositions, mechanical properties, microstructure and microhardness as well as energy spectrum composition analysis. The results indicated that there were certain area of welding “gray spots” mainly composed of manganese oxide at weld failure so that the weld ductility was reduced. As a result, there is cracking at weld fusion line during flaring and forming process of welded rim. The weld quality of 490CL wheel steel for rim is improved by adjusting such welding parameters as reducing flash allowance and increasing pressure of upset forging so that the proportion of weld failure during forming of rim is reduced from 1.5% to 0.3%.

The dynamic CCT curve of low carbon high niobium steel is determined and drawn as well as the effects of cooling rate on microstructure are studied through static simulating rolling compression test of low carbon high niobium steel with MMS-200 thermomechanical simulator. The results showed that the microstructure was mainly composed of polygonal ferrite (PF), a little pearlite (P) and small quantity of acicular ferrite (AF) observed when cooling rate was 0.5 ℃/s; the microstructure was mainly composed of acicular ferrite (AF) and pearlite disappeared, but certain proportion of polygonal ferrite (PF) was still visible when cooling rate was 1.0 ℃/s; the transformation structure was completely granular bainite (GB) when cooling rate was increased to 2 ℃/s; the transformation structure was mainly composed of granular bainite (GB) and a small amount of ferrite bainite (FB) when cooling rate was increased to 5 ℃/s; the transformation structure was mainly composed of ferrite bainite (FB) and a small amount of martensite (M) when cooling rate was increased to 30 ℃/s.

The IF (Interstitial Free) steel plate is welded into steel pipe for manufacturing condenser pipe of household appliances by a user. There are local spot defects on the surface of steel pipe when it is subjected to conventional hydrostatic test. Such tests on chemical compositions, microstructure of defect and non-metallic inclusions of spot defects as well as mechanical properties and metallographic microstructure of the steel plate with base metal are carried out with such means as metalloscope and scanning electron microscope. The results showed that there were abnormal microstructures at the spot defects. The abnormal microstructures contain such alloying elements as Cr and Ni, which are different from the chemical compositions of matrix. When foreign matter is pressed into welded pipe, its local stress is concentrated. During hydrostatic test, the leak points of pressuring are at the foreign matter which is weakly combined with matrix. In order to avoid such surface defects, it is necessary to strengthen quality monitoring during the whole production and processing processes of welded pipe to prevent foreign matters from pressing into matrix to destroy its continuity so that the steel quality is reduced.

During the stamping process of components and parts of computer case, there is blackening phenomenon on the surface of galvanized fingerprint resistant plate of Baotou Steel so that the appearance quality after spraying by user is seriously affected. The microscopic morphology of galvanized plate after stamping is analyzed by microscope and scanning electron microscope (SEM) aiming at the defect. The results showed that the passivation film on the surface of galvanized plate of Baotou Steel dropped out during stamping process as well as the exposed Zn oxidized and turned black. It is effectively solved by adjusting film thickness and proportion of poly tetra fluoro ethylene in passivating liquid.

In the paper, it is introduced a new type of wear resistant and low temperature resistant pearlitic rail with excellent performances is developed through designing material compositions and studying heat treatment process aiming at the operating environment of railway in alpine regions and performance requirements for service of rail. The test results showed that the improvement of impact energy of test steel at -40 ℃ was not obvious by adding 0.10% Ni on the basis of the chemical composition of 0.66%C-0.45%Si-1.10%Mn, but impact performance was more stable than that of test steel without Ni. After the heat treatment of test steel is started and temperature is increased to 780 ℃, the abnormal microstructure, martensite could be prevented to be generated as well as microstructure is pearlite and a small amount of ferrite and impact energy at -40 ℃ could reach 20.1 J.

The targeted optimization and improvement measures are proposed by summarizing and analyzing the existing quality problems of ER70S-6 welding wire steel. The emphasis is strictly controlling such key indicators as chemical composition range, gaseous nitrogen content, dimensional accuracy and microstructure of ER70S-6 welding wire steel. After tackling the problems, rates of reaching the standard for internal control of C, Si, Mn, and N contents are improved, class C accuracy of dimensional deviation is improved as well as abnormal duplex grain structure is eliminated. The drawing results of users showed that the quality of optimized welding wire steel were further improved, which could meet the requirements of high speed drawing with drawing speed of over 28 m/s.

In the process of producing HRB500E rebar for domestic manufacturers, there are often low strength-to-yield ratio or a small amount of nonconformity. In this paper, the comparative experiment of niobium vanadium composite rebar and vanadium nitrogen rebar manufactured with industrial trial production is carried out. The results showed that the strength-to-yield ratio of rebar was increased by 0.03 with the niobium vanadium composite process, ferrite transformation was delayed due to presence of niobium, pearlite content was increased by about 10 percentage points so that tensile strength was increased; vanadium nitrogen alloy was relatively reduced due to the addition of niobium so that its precipitation strengthening and fine grain strengthening effects were reduced as well as yield strength of rebar was slightly decreased. The practices show that the strength-to-yield ratio of rebar and seismic resistance of HRB500E rebar are significantly improved with the niobium vanadium composite process.

There are often such phenomena as spillage, firing, scratch of foreign objects and blockage as well as such failures as off tracking, slipping, scratch and tearing for conveyor belt of iron and steel enterprises. Moreover, the causes of various failures are analyzed, advantages and disadvantages of using various switches for belt failure detection are compared, a method of detecting various failures with images is proposed as well as adaptability of 2D and 3D image detection methods are compared. At last, the architecture of establishing intelligent belt detection platform for iron and steel enterprises is briefly described.

In this paper, the sealing device for patchhole of oxygen lance is redesigned based on the infinite space submerged turbulent jet theory and characteristic test of dominant frequency of oscillation for double-hole jet aiming at such phenomena as spill over of flue gas and flare-up often occurred at nitrogen sealing at oxygen lance of gasification cooling flue for converter. The new nitrogen sealing device adopts the design of seal chamber and double row of inclined holes are set on nitrogen seal seat as well as the aperture and angle of inclined hole are reasonably designed combining with theoretical calculations. It is applied on new 1^# converter of Steel-making Plant of Baotou Steel, in which the phenomenon of “smoking” in process of converting at oxygen lance as well as the frequency of cleaning and changing nitrogen seal cap for operators are reduced so that recovery amount of coal gas is improved. The engineering applications show that the modified sealing device is with such advantages as reasonable design, simple equipment and safe operations.

When dry mechanical pump system is used to vacuumize for such vacuum refining systems as VD, VOD and RH, a large amount of dust generated in liquid steel will enter vacuum pipe with process gas. In order to protect vacuum pump, the precipitator needs to be installed in front of mechanical vacuum pump to remove dust in process gas. It is common to add a cyclone dust collector in front of bag filter so that occupied area is large as well as costs and operating costs are high. The precipitator introduced in this article is with the integrated structure of cyclone and bag. These two parts are installed in two compartments mode within one precipitator so that occupied area is small and costs are low. The integrated precipitator is with such characteristics as high dust removal efficiency, small pressure loss as well as convenient and rapid maintenance and repair through optimizing structural design so that long-term safe operations of dry mechanical vacuum pump are ensured.

In this paper, the combined process of low-nitrogen combustion+calcium-based desulfuration with fixed bed is proposed for flue gas treatment of heating furnace thorough comparing current common desulfurization technology with active carbon, SDS sodium-based desulfurization technology, calcium-based desulfurization technology with fixed bed and dry desulfurization technology with highly active calcium powder in metallurgical industry as well as selecting the desulfurization and denitrification technologies suitable for conventional walking beam reheating furnace of steel rolling mill by taking the ultra-low emission transformation for conventional walking beam reheating furnace of steel rolling mill as an example. After on-site implementation, the nitrogen oxides, sulfur dioxide and particulate matter in flue gas could all meet the ultra-low emission requirements so that the combined process could provide reference for enterprises in the same industry.

The treatment of high-salt wastewater has always been a problem for production enterprises since its salt content is high as well as it is difficult to be treated and cannot be directly discharged into the environment. The harmless treatment of high-salt wastewater is achieved by combining such technologies as membrane treatment, ozonation and evaporation crystallization as well as the salt in water is concentrated into such crystalline salts as sodium chloride and sodium sulfate. As a result, the treated water is for recycling circuit.

In order to remove the calcium and magnesium ions in ammonium sulfate wastewater, ensure subsequent trouble-free operations of water treatment process, improve quality of ammonium sulfate solid and recover magnesium resource, the calcium and magnesium ions in ammonium sulfate wastewater are removed with solvent extraction method in experiment. The P₂₀₄ and kerosene are used as extractant as well as pH value of ammonium sulfate wastewater and saponification degree of P₂₀₄ are adjusted so that the step-by-step removal of calcium and magnesium ions in ammonium sulfate wastewater is realized. The data support for industrial applications of this method is provided by such experimental conditions as determining pH values of the solution and comparing.