The waste emulsion is the oily wastewater in high concentration discharged in steel rolling process and the key of treatment is demulsification. In this paper, the suitable demulsification methods are selected through experimental study as well as the experimental conditions of electrooxidation demulsification and chemical flocculation demulsification are selected. The results showed that the most suitable demulsification method was electrooxidation, its optimum current range was 2.0~3.8 A and optimum voltage range was 140~200 V; the optimum coagulant for chemical flocculation demulsification was polyaluminum chloride. When the quantity added to is 1.5 g/L and pH value is adjusted to 7~9, the chemical oxygen demand (COD) in waste emulsion reduces to less than 8 000 mg/L, oil content reduces to less than 1 000 mg/L and suspended solids reduces to less than 1 500 mg/L.

In this paper, the dimensional changes of austenite grain for X80 pipeline steel with such conditions as different heating temperatures and heating times are studied with the thermal simulation method. The results showed that the austenite grain coarsening was obvious, which was from the minimum, about 35 μm to about 120 μm with the increase of heating temperature and soaking time; but if the soaking time was shorter (1 min), the austenite grain size still remained within 80 μm even if it was heated at 1 280 ℃, which showed the essence of fine grained steel. As a result, the mathematic model of austenite grain growth for X80 pipeline steel was obtained by the regression of experimental data, which could provide basis for industrial production.

The super large deposit of Nb, rare earth and iron in Bayan Obo is currently one of the mines with the most varieties of new minerals discovered in the world. The dolomite type ore with Nb and rare earth is the most widely distributed ore type in this area as well as it is with significant meanings to research its characteristics such as mineralogy. The dolomite type ore in East Mine of Bayan Obo is collected through field work as well as the petrographic identification and process mineralogy analysis are carried out. The results showed that the dolomite was distributed in subidiomorphic-xenomorphic granular form among fluorite, its particle size was uniform and generally 0.1~0.3 mm; the magnetite was mostly disseminated in subidiomorphic aggregation among fluorite and dolomite and its particle size was generally 0.3~1.0 mm. The main oxides of ore are CaO and MgO as well as the content of dolomite in this type of ore could reach 70%.

In this paper, a new-type accurate online measurement system of quantity of dry ore in pulp pipeline is introduced. The system is with the diaphragm pump as pulp conveying power and measuring equipment of pulp volume, pulp density is measured with γ-densitometer and grade of iron concentrate is with manual measurement, quantities of dry ore and backwater in pulp are calculated accurately with mathematical model; various data are processed automatically with information technology and results are published through the server of settlement report. Meanwhile, an automatic online calibration system is designed and manufactured to calibrate the calculated values regularly.

The effect of no visible smoke dust is achieved through deeply analyzing the more serious emission of smoke dust after transform the unorganized emission of 1^# and 2^# coke ovens of Baotou Steel Qinghua Coal Chemical Engineering Co., Ltd. as well as transforming equipment and facilities of coal car and relevant equipment of gas export system, which is with a certain reference value to transform unorganized emission of tamping coke oven as well as control fugitive emission of smoke dust in the coaling process of tamping coke oven.

The gas flow distribution and gas utilization rate are improved by optimizing the charging system as well as adjusting the material layer thickness of coke and ore aiming at the long-term higher fuel ratio of 5^# blast furnace of Baotou Steel; the smelting is strengthened by such measures as increasing furnace top pressure, hot air temperature and oxygen enrichment rate; meanwhile, the efficiency of tapping iron in front of furnace is improved, daily operations of blast furnace are strengthened and standard work is carried out so that the target of increasing production and reducing consumption is realized. The fuel ratio of 5^# blast furnace reduced from 598.73 kg/t on average in 2020 to 556.9 kg/t, which was the best level in history.

According to the smelting process of converter, the heat balance of converter is calculated with the heat balance calculation method. The influences of different molten iron conditions, production processes and temperature control on improving the addition of scrap steel are calculated. The specific measures for improving the scrap ratio of basic oxygen furnace(BOF) are put forward by analyzing the factors affecting change of scrap ratio of BOF as well as studying the relations between scrap ratio and smelting process conditions of BOF, which are as references for relevant steelmaking plants.

The large-grained ribbed Al₂O₃ inclusion is the main cause of cracking through analyzing the cracking in process of stamping beam steel BT700L. In order to improve the size and morphology of inclusion in product, the rare earth Ce is added in production of beam steel BT700L. Since the affinity of rare earth Ce and oxygen is very strong, the rare earth Ce in molten steel reacts with oxygen and generates rare earth oxide (RE₂O₃) coming up to slag so that the yield of rare earth Ce in steel is extremely low. It could be improved effectively through optimizing and controlling the content of Ce in molten steel of steelmaking and continuous casting, oxidability of slag as well as such process as protective casting of continuous caster. Moreover, the atomic radius of rare earth Ce is greater than that of iron atom and rare earth Ce could denature inclusions in steel. It is found that the size of inclusion in product becomes small, morphology of inclusion spheroidizes and low temperature impacting property of product is effectively improved after add rare earth Ce into molten steel through studying and analyzing adding rare earth Ce into beam steel BT700L.

The 550 MPa grade hot rolled axle housing test steel is rolled in laboratory with the design of medium carbon content+micro alloy Nb and Ti as well as controlled rolling and controlled cooling process. The results showed that the effects of adding moderate rare earth Ce into test steel on its microstructure and strength were not obvious, rare earth Ce reduced the grade of inclusion (class B) in test steel, low temperature impact energy of test steel with rare earth was obviously better than that of test steel without rare earth and fatigue property of axle housing test steel was improved by rare earth Ce.

The hot bends are important components of oil and gas transmission pipeline, so the research and development of hot rolled band for L415M hot bends are with important significances. The band is with low carbon and microalloyed composition of Nb-Ti-Mo, high cleanliness smelting as well as reasonable controlled rolling and controlled cooling process, so it is with excellent comprehensive properties, its microstructure is fine and uniform ferrite and pearlite and their grain size is grade 12.0 as well as the inclusion control is good. Its dimensional accuracy is high as well as surface quality and strip shape are good. After the band is manufactured to hot bends, their overall performances are excellent so that they could meet the operating requirements of users. As a result, the bulk sales and successful applications are realized as well as product quality is well appraised by users.

The 800 MPa grade hydropower engineering steel with low welding crack sensibility is developed through smelting test steel with 100 kg vacuum induction furnace as well as thermal mechanical control processing (TMCP), quenching and tempering processes adopting the alloy system route of low carbon, carbon equivalent (Ceq) and welding crack sensibility index (Pcm) in laboratory. Such mechanical properties as the strength, impact and bending of test steel are tested as well as its microstructure and fracture morphology are analyzed with the optical microscope (OM) and field emission scanning electron microscope (SEM). The results showed that its microstructure at room temperature was tempered sorbite, all its mechanical properties were excellent, its yield strength, tensile strength and elongation after fracture were 788 MPa, 842 MPa and 18.1%, low temperature impact absorbing energy at -40 ℃ was 197 J, strength and toughness well matched as well as welding crack sensitivity index was low, which could meet the performance requirements in use.

In this paper, the causes of cracks are analyzed with the macro morphological observation, chemical composition analysis, metallographic microstructure inspection, scanning electron microscopy and energy spectrum analysis aiming at the surface cracks of H beam web of a large domestic steel plant. The results showed that there was decarburization in the microstructure near cracks as well as there were secondary oxide particles containing silicon and manganese and the characteristic element sodium near matrix, which indicate that the cracks are generated during continuous casting of casting blank and finally formed on the surface of web.

The requirements of non-chrome passivation film for galvanized home appliance plate are mainly focused on such aspects as corrosion resistance, stamping and powder injection performance. In this paper, it is mainly introduced the influences of film weight on the corrosion resistance of non-chrome passivation steel plate, influences of powder injection process parameters on adhesion of powder as well as dynamic friction coefficients of non-chrome passivation products with different compositions and their main applications. In order to achieve good effects, strict control is required in the process of industrial production and end use.

The material characteristics of seamless pipe for 850 MPa drill pipe of rotary drilling rig manufactured by Baotou Steel Tube Co., Ltd. such as mechanical properties, microstructure, ductile-brittle transition temperature, torsional strength and bending fatigue are tested and analyzed. The results showed that its such technical indexes as the mechanical properties, content of nonmetallic inclusions, grades of grain size and banded segregation could all satisfy the requirements of applying 850 MPa high strength and high toughness drill pipe of rotary drilling rig. Moreover, it is with such advantages as low ductile-brittle transition temperature, high torsional strength and good resistance to bending fatigue.

The components of Cr-Mo microalloyed steel are designed and developed according to the performance requirements of C110 oil casing with resistance to hydrogen sulfide corrosion as well as the industrial tests are carried out based on the research results of characteristics of steel in laboratory. The results showed that the designed product was with good strength and toughness after heat treatment of quenching and high temperature tempering, which could satisfy the requirements of mechanical properties of standard; while when the yield strength satisfied the standard requirement and was less than 800 MPa, the tube was with excellent resistance to hydrogen sulfide stress corrosion and the percent of pass for test of resistance to hydrogen sulfied was more difficult to achieve 100%.

The design of power supply system in workshop needs to consider such factors as the reliable power supply, economic rationality, advanced technology and future development. In this paper, such aspects as the design principles and thoughts of high and low voltage power supply systems in steelmaking workshop of a converter project are discussed. The high voltage power supply system is elaborated mainly from such aspects as power distribution system and relay protection as well as the low voltage power supply system is elaborated mainly from such aspects as the system partitioning, power distribution system, safe power supply and security measures.

In the paper, the scheme of establishing a self diagnosis model for high speed rolling bearing is proposed considering the complexity of rolling bearing fault diagnosis and combining with the difficulties of rolling bearing fault diagnosis for equipment on site. The original vibration signal of rolling bearing for high speed gear box is decomposed using the wavelet packet, then frequency domain signals in different frequency bands in decomposed original vibration signal are reconstructed and the characteristics of shock pulse energy for rolling bearing fault of reconstructed frequency domain signals are extracted respectively. The extraction of characteristics for rolling bearing fault of high speed gear box is realized and they are used for establishing the self diagnosis model for high speed rolling bearing through comparing the characteristics of impact energy for rolling bearing extracted from each frequency band after reconstruction as well as extracting frequency band signals sensitive to energy changes aiming at different types of rolling bearings.

The coiler in production line of hot continuous rolled strip steel is the only equipment for coiling strip steel after rolling and its stability of working condition directly affects the stable production of production line, yield and appearance quality of coil of strip. The level of stiffness of wrapper roller for coiler is the core factor determining stability of coiler. In the paper, the concept of stiffness of wrapper roller for coiler in production line of hot continuous rolled strip steel as well as the significances and methods of static test are elaborated. The analysis sheet of stiffness of wrapper roller is obtained through tests as well as collecting, analyzing, summarizing and calculating related data. Guide the craft personnel to set and optimize parameters as well as equipment personnel to eliminate defects purposefully to ensure stable operation of coiler, reduce coiling accidents and improve yield as well as ensure coil shape and appearance quality of strip steel.

In order to realize the intellectualization and informatization of coal blending management for coking, the optimized coal blending system composed of single coal database, coke quality prediction module, cost performance evaluation module of single coal and optimizing design module of coal blending is independently developed. With the Access as background database, the functions of each module are realized through such algorithms as invoking programming solver by VB+EXCELVBA hybrid programming technology and multiple linear regression. The production applications show that the system plays a prominent role in reducing production cost of coking and stabilizing coke quality.

In the paper, such problems as printing wrong label, wrong labeling, high labor intensity of operators and potential safety hazards due to the cross operations with crane on site aiming at the manual labeling for outer and inner surfaces of steel coils after skin rolling in the skin-pass rolling production line. The mutual communication and control of each system are completed as well as the automatic labeling with mechanical arm instead of manual work is realized through designing the electrical automation control, upper computer control, motion control of mechanical arm, clamp and pneumatic system of automatic labeling system for steel coils in the skin-pass rolling production line so that the labor intensity of operators reduces and life safety of personnel is ensured. The automatic labeling system can be as the reference for replacing the manual operation with mechanical arm under the similar conditions.

In this paper, it is introduced the audio intelligent recognition system for industrial equipment fault is designed and integrated into the patrol robot. The robot could collect real-time audio data of equipment in inspection area and transmit them to the edge computing module inside itself to automatically carry out model training, extract and compare acoustic feature as well as give an alarm in time when there are abnormal characteristics when it is doing inspection tasks so that the recognition of internal fault of equipment could be realized. As a result, the detection is more comprehensive and accurate through solving the problem of limitation of visual detection.

The zinc and copper are separated from lead and tin based on the characteristics that ammonium hydroxide, zinc and copper form complex ions as well as ammonium hydroxide, lead and tin form precipitates. The effects of the acidity of zinc, lead and tin titrated with ethylene diamine tetraacetic acid (EDTA), added quantity of thiourea and ammonium fluoride as well as buffer solution on determination are tested. The test results showed that the pH value of solution acidity was 4.5~5.0 and selectivity of titration was higher when zinc was titrated with EDTA; pH value of solution acidity was 5.0~6.0 when determined lead and tin as well as the colors at titration end point changed sharply. The interference of coexisting ions could be avoided by adding sulfosalicylic acid. The determination range of this method is 0.50%~20%, relative standard deviations of zinc, lead and tin in tin bronze samples are all smaller than 2.0% through analysis as well as adding standard recovery is 97%~103%.

The design budget estimate is the important basis for investment cost control of metallurgical engineering. In this paper, it is briefly introduced as well as it is analyzed the common problems in the process of preparing design budget estimate for metallurgical engineering such as investors do not pay enough attention to the preliminary design budget estimate, content provided by designer is incomplete and level of budget estimate preparers is insufficient. Moreover, the corresponding improvement suggestions and several countermeasures to improve preparation quality of budget estimate are given-select accurate prices of materials and equipment, implement strict review and approval process as well as carry out comparative analysis with the feasibility estimate to ensure the accuracy and completeness of budget estimate.