The axle housing is one of the main components of traveling system for vehicle. The 650QK steel developed in laborotary is with the component design of medium carbon as well as trace amount of Nb, Ti and V alloy elements are added, the microstructure is fine and even ferrite, pearlite and bainite, grain size is grade 12~13, yield strength is 664~671 MPa, tensile strength is 762~794 MPa, elongation is 20.0%~21.5%, cold bending property and low temperature impact toughness are good, low temperature impact toughness at -60 ℃ reaches 127 J, ductile-brittle transition temperature is lower than -60 ℃, ultimate fatigue strength is 270 MPa as well as synthesized mechanical properties of material are good, which could provide the technical index of basic performances of material for industrial production.

In this paper, the 390 MPa grade test steel for offshore platform is obtained with the component system of low C, high Mn and Nb-Ti microalloying and reasonable adding sequence of alloys during smelting as well as the controlled rolling and controlled cooling process. The test results showed that the upper yield strength was 488 MPa, tensile strength was 550 MPa, elongation after fracture was 30%, longitudinal and transverse impact energies at -20 ℃ were 242 J and 155 J; the microstructure was fine ferrite and pearlite as well as the inclusions were fine and with the size of 2~3 μm; after the welding thermal simulation test with welding heat input of 100 kJ/cm for test steel, the mechanical property test and metallographic structure were with the basic characteristics of steel with large heat input welding as well as the products are verified to be with good low-temperature impact toughness and welding performances.

In this paper, the relatively perfect intelligent weighing system is constructed through adjusting and optimizing the existing business process of weighing, combining with various anti-cheating means as well as making full use of information technology in the new age. Moreover, the weighing information as well as information of door control system and chemical inspection system is integrated combining with respective weighing characteristics of motor truck scale and rail weighbridge to solve such practical problems as the continuously increased variety of weighing materials for materials measurement, more complex business and reduction of weighmen. As a result, the levels of measurement control and informatization management as well as efficiency of flow of materials are improved to meet the requirements of informatization and automation for current weighing system.

In this paper, the sintering productions with such SiO₂ contents in sinter as 4.75%, 4.85%, 4.95%, 5.15% and 5.30% are carried out based on the effects of different SiO₂ contents on sinter with 500 m² sintering machine. The results showed that the drum strength of sinter was increased with gradual increase of SiO₂ content in sinter when SiO₂ content in sinter was less than 5.15%; the drum strength of sinter was optimum when SiO₂ content in sinter was about 5.15%, which was increased by 3% compared with that of 4.75% and average particle size was increased by 1.77 mm; the drum strength changed slightly with continuous increase of SiO₂ content when SiO₂ content in sinter was increased from 5.15% to above 5.30%. The analysis on the microstructure of sinter with different SiO₂ contents showed that the prismatic tabular calcium ferrite was increased with the increase of SiO₂ content and the dicalcium silicate of partial region was with large area enrichment. With the high proportion of self-produced concentrate of Baotou Steel, the SiO₂ content is controlled at about 5.15%, drum strength of sinter can reach above 79.5% and average particle size can be improved above 19 mm.

The requirements for surface quality of non-oriented silicon steel are very high as well as such defects as pits and color differences are not allowed on the surface, otherwise, the normal use will be affected. The pits on surface account for a larger proportion in surface quality defects so that product delivery and economic benefits are affected. The analysis results indicated that the accretion for furnace roller was the main cause of pit defects on steel plate. The poor cleaning quality of steel plate, high oxygen content in the atmosphere of annealing furnace and wear of furnace rollers are the main causes of accretion for furnace roller. The accretion for furnace roller is significantly reduced by adopting such methods as improving the cleaning quality of incoming steel plate, optimizing atmosphere environment of annealing furnace and ensuring quality of furnace rollers so that the surface quality of steel plate and qualification rate of silicon steel products have been significantly improved.

In this paper, the dissolution methods of iron ore and slags are studied. The decomposition method of preliminarily dissolving with hydrochloric acid followed by treating the residue with mixed flux of sodium carbonate-boric acid is applied. The analytical spectral lines with high sensitivity and fewer interferences are determined as analytical spectral lines through optimizing and selecting the analytical spectral lines of lanthanum, cerium, praseodymium, neodymium and samarium by experiments. Moreover, the contents of such five elements as lanthanum, cerium, praseodymium, neodymium and samarium are determined simultaneously with ICP-AES. The results showed that the lower detection limit of lanthanum, cerium, praseodymium, neodymium and samarium in iron ore and slags was 0.005 0%, the upper detection limits of rare earth elements in iron ore were 5% for La, 10% for Ce, 1% for Pr, 2% for Nd and 1% for Sm as well as all the upper detection limits of rare earth elements in slags were 0.500%.

In the paper, it is introduced the detection analysis on non-metallic inclusions in rail head. In order to scientifically characterize the quantity, size and distribution of inclusions, the new method for detecting inclusions is explored. A new vertical detection surface is added by taking the sample position with the K method for cleanliness of oxide in the EN 10247—2017 standard, that is, such two sampling methods as vertical plane and inclined plane are adopted separately. The quantity, size and distribution of inclusions in rail head are statistically analyzed with fully automatic optical microscope as well as the compositions of typical inclusions are analyzed with scanning electron microscope and energy disperse spectroscopy. The distribution and sources of inclusions in the rails of Baotou Steel are comprehensively analyzed, which provide technical support for further improving and controlling the cleanliness of rail steel.

Four new types of coal are increased through developing independently and introducing the new types of coal in Shanxi and Inner Mongolia as well as utilizing the SXLLSJM、SXJM and HDSJM, part of which is instead of such types of coal with tension supply as ZYDM and LLGHM. As a result, the scope of coal used for rammed-coal coking is expanded, tension trend of using coal is relieved, the existing coal blending structure of rammed-coal coking is optimized and coke quality is improved. The ash content of coke is reduced and the hot strength of coke is increased, which provide the strong fuel support for the stable and trouble-free operation of blast furnaces of Baotou Steel.

In the paper, the restraining factors affecting recycling fly ash of sintering machine head and blast furnace bag are discussed as well as the key technologies of extracting such valuable elements as Zn, K and Na from the fly ash are studied by analyzing its characteristics and disposal status. The technical plans for comprehensive utilization of fly ash of sintering machine head with high alkali metal content as well as fly ash of blast furnace bag with high zinc and alkali metal contents are proposed combining with such cases as salt extraction technology by washing for fly ash with high alkali metal content, zinc extraction technology with pyrogenic and wet processes for fly ash with high zinc content and reduction technology of electric arc furnace for iron-bearing dust as well as evaluating their merits and demerits. After implement the plans, the disposed fly ash could be recycled for sintering as well as products of Zn, K and Na could be sold externally so that the economic benefits are considerable and the problems of land occupation and environmental pollutions could be solved.

The mineral species that have been found in Bayan Obo ore deposit are sorted and recorded based on the list of mineral species in Bayan Obo mining area in Mining and Metallurgical Technology of Baiyuneboite as well as the research achievements of minerals of Bayan Obo are collected combining with such documents as Mineralogy of Bayan Obo. The results showed that there were 172 types of minerals in the list of mineral species in Mining and Metallurgical Technology of Baiyuneboite after correct obvious errors, the minerals reached 191 types by supplementing the minerals that were not recorded in Mineralogy of Bayan Obo; a total of 209 types of minerals have been found in Bayan Obo ore deposit so far, together with the newly found minerals and new minerals.