In the paper, the dedecting and analysis on fixed flash welding joints of U71MnG high speed rail are introduced. The welding joints of different wave heights by ultrasonic testing are compared and analyzed as well as their causes are analyzed, which provides the basis for adjusting welding process so that the quality of welding joints is improved.

The fluorite is widely distributed in the mining area of Bayan Obo. Its degrees of mineralization are different for each ore block, so it is classified as "four generations". The distribution characteristics of fluorite in different generations are studied by means of microscope, XRD and SEM, which prove that the radioactive element Th makes fluorite with the optical property of anisotropism and it has direct influence on the replacement of Ca with Sc.

In this paper, it is introduced the calcium chloride solution is used as dust suppressant for dust suppression operation on dry beach face of tailings aiming at the problem that dust is easy to raise on dry beach face of tailings pond. The concentration of dust suppressant is adjusted in time by observing the moisture and crusting regime of dry beach face after spray the dust suppressant so that the effects of improving the environment of reservoir area and reducing resource loss are good.

The prediction model of coal blending is established with Minitab software so that the problems of large error and low accuracy of coal blending prediction by experiences in Baotou Steel are solved, which plays a stronger guiding role in production. The coke quality can be quickly predicted with the model so that the production of coking coal blending is guided in time as well as the coke quality, the stable and trouble-free operation of blast furnace are ensured. Meanwhile, the range of coal used in Baotou Steel is expanded, high-quality coking resources are saved and costs of coal are reduced so that it is of great significance in application and promotion.

In this paper, the technical scheme of substituting bentonite with cobinder is proposed aiming at the production situation of high ratio of bentonite and high content of SiO₂ for pellets of Baotou Steel as well as the experimental research is carried out. The results showed that the grade of pellets could increase by 0.84 percentage points and content of SiO₂ could reduce by 0.86 percentage points with 8^# cobinder, which can better meet the demands of blast furnace process.

The difficulty of mixing coke powder with retorting coal is solved through such measures as strengthening particle size control of fuel and optimizing the processibility aiming at the retorting coal is with such disadvantages as poor controllability of particle size after cracking, more moisture and non uniform combustion velocity. The maximum proportion of retorting coal is 53% of fuel consumption so that the whole sintering production is smooth, the output increases and quality of sinter is stable. Moreover, the utilization coefficient of sintering machine increases by 0.021 t/m²·h, solid fuel consumption decreases by 5.87 kg/t, content of FeO of sinter decreases by 0.18 percentage points, drum index increases by 2.11 percentage points and the RI increases by 1.77 percentage points.

In this paper, it is systematically summarized the adjustment of upper and lower 3^# blast furnace as well as emphatically analyzed the changes of furnace condition when the fuel in furnace is improved by taking replacing tamping coke with top charging coke for 3^# blast furnace in 1^# Iron-making Workshop of Iron-making Plant as an opportunity.

In the paper, it is introduced the ultra fast cooling production process suitable for hot-rolled dual phase steel is developed based on the CSP production line with short process and its industrial applications are realized. The results showed that ferrite grain became finer and tensile strength increased with the finish rolling temperature decreased; ferrite grain became finer and tensile strength decreased with the medium temperature decreased; the reasonable process parameters were obtained that with the finish rolling temperature of 840 ℃, medium temperature of 670 ℃ and coiling temperature of 170 ℃, the 540 MPa grade hot-rolled dual phase steel with thickness of 6.0 mm produced was with the microstructure of ferrite and martensite, yield strength of 330~360 MPa, tensile strength of 560~590 MPa and elongation of 30%~36%, which met the product requirements very well.

In this paper, the productive process is summarized from the concentration, pH value, granularity fitness and saponification value of emulsion used in Baotou Steel. The results showed that when the emulsion concentration of final stand is within the range of 0.9%~1.1%, pH value of emulsion is within the range of 5.8~6.0 and saponification value of emulsion is greater than 160 mgKOH/g, the reflectance of strip surface is relatively higher, contents of residual oil and residual iron are within a reasonable range as well as surface clearness of strip is better.

The weather-resistant wide and heavy steel plate for bridge with yield strength of 500 MPa has been developed. It is with such comprehensive properties as high strength, high toughness, processing without deformation, resistance to low-temperature fracture and high weather resistance that it can meet the requirements of GB/T 714—2015 standard as well as is suitable for using in extremely cold areas and without coating.

It is the key factor to strictly control the contents of C, Mn, P, S and gas elements in steel for improving purity of molten steel, decreasing segregation of casting blank and improving H₂S corrosion resistance. The loss of strength caused by low manganese can be made up by adding the alloy element Cr. It is the important link to reasonably formulate the process system of smelting, continuous casting and hot rolling for guaranteeing products to meet user requirements. The chemical composition and process design of L245MS/BMS hot rolled coil produced by Rare Earth Steel Plate Plant of Baotou Steel are reasonable, it is purified as well as with uniform microstructure and good synthesized mechanical properties, especially the resistance to hydrogen induced cracking and stress corrosion. This design scheme is mainly suitable for producing the export products.

In this paper, the actual demand of cold rolled low carbon products for current users is introduced. The process optimization of SPCC for the first trial production with the continuous annealing production line of Rare Earth Steel Plate Plant of Baotou Steel is to reduce the yield strength range, eliminate yield platform and improve mechanical properties of products so that the yield strength is controlled at lower than 230 MPa, which could meet the market requirement.

In this paper, the key technology of a new generation of cold-rolled fatigue-resistant glassed steel for inner container is described. The chemical composition and cover annealing process of cold-rolled low carbon plate are designed as well as the mechanical properties and metallographic structure of the cold-rolled plate prepared are analyzed. The experimental steel plate is made into inner container of water heater as well as the enamel and bulge tests are carried out. The results showed that the fatigue resistance of inner container of water heater was significantly improved and the times of pressuring could reach more than 150 000 when the mechanical properties of the cold-rolled steel plate were controlled at yield strength of 220~270 MPa, elongation≥38% by adding proper amount of Nb and rare earth element as well as with the annealing process so that it is with good enamel property, stamping formability and fatigue resistance.

The detection study on low temperature impact fracture and microstructure of BT100H sleeving steel with Zeiss Axio Obserevr D1m metallographic microscope and EVO 50HV scanning electron microscope is introduced. The research showed that the low temperature impact toughness, especially the transverse impact toughness of material was improved by rare earth as well as the rare earth also was with a certain function of refining microstructure.

In this paper, it is mainly discussed the process control and analysis on microstructure and properties of Q420NQR1 weather-resistant hot-rolled H beam for railway vehicles produced with section of beam blank. As a result, its microstructure and properties all meet the design requirements as well as the product performances meet requirements of stability, reliability and safety for the materials of railway vehicles through such process controls as its chemical composition, smelting, heating and rolling.

In the paper, the bending defects of electrode flat steel are studied as well as the process, operations and equipment for them are analyzed. The thermal stress and deformation stress of rolled pieces are improved, bending of flat steel is reduced, first pass yield of hot rolling of electrode flat steel is improved, labor intensity of workers is reduced, product delivery time is shortened, market competitiveness is enhanced and market share is increased through a series of improvement measures such as controlling heating temperature, improving pass system, operation standardization as well as the technological improvement of transportation and cooling equipment.

In this paper, the optimization technology of lubricating and flushing system for roll gap of 2 250 mm hot finishing mill of Baotou steel is introduced. The temperature of flushing system is controllable after optimization and the system can be without affecting by external steam fluctuation so that the effect of rolling lubrication is greatly improved and rolling force is reduced, which provide guarantee for smooth production on site.

In order to realize the print of two-dimensional code tag for steel products, the two-dimensional code tag print system is designed and developed. It is with the B/S configuration pattern based on the existing ERP platform development. The front-end development is with JSP technology and the back end is with Java and XML to control business logic. After the system processes the data collected by ERP, the results based on parameter determination are stored into two-dimensional code, then the two-dimensional code document of steel products based on the tag templates is output and printed out.

In this article, it is introduced the power supply device of medium frequency induction melting furnace is improved aiming at the faults and deficiencies in the operation of common parallel resonant power supply of 25 kg intermediate frequency induction furnace in a laboratory. The results showed that the load current of parallel inverters changed from rectangular wave to approximate sine wave and the adjustment range of trigger signal became wider after improvement so that constant power output could be achieved. As a result, such shortcomings of common parallel inverters as small capacity and output without full power are overcome.

The influences of reclaimed water on circulating cooling water system in the recycling process are studied through single factor corrosion test and corrosion inhibition test of reclaimed water in iron and steel enterprises. The results showed that the corrosion of Cl^- and in water to the system was serious during the operation of circulating cooling water system. The actual operation status of circulating cooling water system can be effectively improved, service life of system equipment can be improved and operation costs can be reduced by selecting corrosion inhibitor and reasonably master its dosage, which is of guiding significance for regeneration and reuse of industrial wastewater in iron and steel enterprises.

Under the premise of not changing the original industrial pattern of plant, adjust measures to local conditions to cultivate different levels of ecological garden landscape by investigating and analyzing the landscaping system of Baotou Steel. Moreover, three-dimensional green quantity of plant is increased by strengthening three-dimensional afforesting, especially such measures as the vertical greening, sky courts, parking lot greening and slope protection and revegetation. Meanwhile, such ecological re-cultivations as the afforestation of northern raw material region, surrounding of tailings lake and mine can be popularized energetically to supply a deficiency, reasonably allocate the garden environment landscape and effectively improve the ecological green quantity in park of Baotou Steel.

The experiments for surface roughness of sheet metal with the DIN EN 10049 and GB/T2523 two test methods are compared, verified and explored according to the domestic and international production testing conditions of automobile leaf-spring. It is found that the stability and accuracy of gaussian filter are better than those of 2RC filter, stability of test data for sheet metal with different surface roughness ranges has no connection with the number of testing points as well as the surface roughness has no connection with plane grain trend through comparing the requirements of filter for testing surface roughness, number of test points for samples and test direction, which provide guidance for production testing with different standards.

After the sample was completely dissolved by dilute nitric acid, the method for determining contents of impurity elements (Al, Fe and Sb) in zinc flakes with inductively coupled plasma optical emission spectrometer (ICP-OES) was established by selecting Al 167.079 nm, Fe 238.204 nm and Sb 206.833 nm as the analytical line. The results showed that the detection ranges of Al, Fe and Sb were 0.50~5.0 μg/mL, 0.05~0.50 μg/mL and 0.05~0.50 μg/mL respectively. The linear correlation coefficients of calibration curve were all over 0.999 and the detection limit of method was 0.018~0.100 μg/g. The production samples of zinc flakes were determined according to the experimental method, the relative standard deviations (RSD, n = 10) were all smaller than 5.0% and adding standard recovery was 98%~102%.

Innovation is the primary driving force for development, so grasp innovation is development and seeks innovation is the future. The present situation of scientific and technological innovation of Baotou Steel is with not only advantages of resources and equipment, but also such problems as insufficient innovation motivation. Based on the investigation results for scientific and technological innovation of Baotou Steel, the following conclusions are obtained by analyzing and thinking. At present, Baotou Steel should strengthen the researches for perfecting scientific research management system, strengthening construction of incentive policies, reinforcing R&D, strengthening construction of scientific research bases, making scientific research plans and formulating innovative strategies. Baotou Steel should pay high attention to the strategic importance and functions of scientific and technological innovation as well as make it become the primary driving force for development of company to accelerate the construction of innovative Baotou Steel.