In this paper, the NM1^# wear resistant steel produced by a domestic manufacturer and NM2^# wear resistant steel produced by a foreign manufacturer are selected to be compared and studied by taking rare earth wear resistant steel NM450F of Baotou Steel as the object of study as well as the corrosion resistance test is carried out with alternate immersion test equipment. The results showed that the loss mass of corrosion was 117.98 g/m² and corrosion rate was 1.64 g/(m²·h) for rare earth wear resistant steel NM450F of Baotou Steel so that its corrosion resistance was better than that of like products at home and abroad, NM1^# and NM2^# wear resistant steels. The rust layer of cross section for rare earth wear resistant steel NM450F of Baotou Steel is the thinnest and it appears to be spherical particle with uniform size to spread to matrix and tendency toward corrosion is the smallest.

The propagation model of shock gas is established by taking the shock gas induced by instability of goaf as research background as well as the change rules of propagation rate are analyzed with the laboratory test that simulates shock gas and numerical simulation method. The study results showed that the model of flow past body of shock gas consisted of stages of uniform motion and accelerated motion; the larger the falling height of roof of goaf, the smaller the proportion of duration of uniform motion stage and the larger the proportion of duration of accelerated motion stage. The study results could provide references for prevention and treatment of shock gas disaster induced by instability of goaf.

In the paper, the rock and ore are divided into three main classes and five subclasses based on iron grade and data of perforating for production in Main Mine of Bayan Obo in recent years as well as distribution rules and space coupling characteristics of contents of F and S in various types of rock and ore are summarized. The research results showed that the main occurrence minerals of element F in Main Mine of Bayan Obo were fluorite and bastnaesite as well as main occurrence minerals of element S were pyrite, pyrrhotite and galena. In terms of distribution of contents of elements F and S, it generally shows the change rule of “increasing first and then decreasing” with the increase of iron grade of ore; in terms of space distribution, elements F and S are most closely related to iron ore, space distribution range of elements F and S is gradually decreased as well as overlapping area is gradually decreased and separated, which shows the distribution characteristic of “alternate zoning with variants” with the increase of contents of F and S.

In the production technology of continuous casting, oriented silicon steel, as a type of “soft steel” in the traditional sense, shows unique physical properties. Its thermal conductivity is relatively poorer, liquid thermal conductivity is approximately 27% lower than that of ordinary carbon steel so that it shows significant weak thermal conductivity. This property makes it easy to be deformed in high temperature environment. Consequently, there are often such surface defects as liquid level fluctuation of crystallizer, bulge and dimple of ingot blank as well as such internal quality issues as center segregation, center porosity and cracks during the continuous pouring production process. These issues directly impact the number of continuous pouring heats. In order to solve these problems, it becomes the key strategy for increasing the number of continuous pouring heats to design and implement reasonable cooling regime and casting speed.

The assembly for pretwisted blades of turbine has significant effect on its overall performance. In this paper, its deformation mechanism is studied and simulation experiments are carried out through finite element model to verify the accuracy of assembly system for pretwisted blades. The process parameters of manually tapping blades are obtained using high speed camera and piezoelectric type impact sensor as well as corresponding mathematical model is established. The parameters of this model are adjusted in software to design the assembly system for pretwisted blades of turbine. The final results indicated that sufficient impact could be generated by the assembly system to meet assembly requirements when the range of air source pressure was between 0.4 MPa and 0.6 MPa so that feasibility and effectiveness of the system were verified.

With the rapid development of artificial intelligence, automatic driving technology and intelligence of mining, unmanned intelligent vehicles in mines have gradually become the important tool for improving operation efficiency in mines, reducing accident incidence and saving costs. In this paper, the key technologies, functions and challenges faced of unmanned intelligent vehicles in mines are systematically analyzed. First, the application background of driverless technology in mine environment is discussed as well as such key technologies as perception, decision making, control and communication it needs in mining operations are analyzed. Second, the core functions of unmanned intelligent vehicles in mines including auto drive and path planning, collaborative operations, safety and exception handling are proposed. Finally, the technical challenges faced by unmanned intelligent vehicles under the working conditions of complex geographical environment, severe weather and high load are analyzed as well as the solutions are proposed and development trend of unmanned intelligent vehicles in the future is prospected. This paper is aimed to provide the theoretical supports and technical references for research and applications of unmanned intelligent vehicles in mines.

In this paper, the causes of surface defects for 310 zed beam rolled by YQ450NQR1 continuous casting billet produced with cross section of bloom (320×415 mm) by 7^# continuous casting machine in Steel-making Plant of Baotou Steel are analyzed and control scheme is proposed so that the yield of product is improved. The tongue-shaped defects in rolled products are determined to be caused by the surface crack at corner of continuous casting billet by analyzing the macrostructure and microstructure of continuous casting billet and rolled products with metallographic microscope and scanning electron microscope. The qualified rate of YQ450NQR1 continuous casting billet is improved from 90.5% to 98.5% and stable control of product quality for 310 zed beam is realized through reducing the water amount and optimizing uniformity of water crevice for crystallizer to improve the uniformity of continuous casting billet cooled in crystallizer as well as taking such measures as reducing the specific water amount of secondary cooling, increasing casting speed to increase the surface temperature of entering tension leveler and optimizing slow cooling regime.

Dust removing fan is the key equipment of blast furnace production system. If there is abnormal vibration of fan equipment, the fault alarm would be triggered. As a result, there is not dedusting air volume in the environmental dedusting system so as to cause such environmental pollutions as flying dust. In the paper, it is proposed the causes and solutions for vibration fault of motor for dust removing fan for blast furnace by taking the basic principle of “high efficiency, high quality, low cost, green and environmental” as well as elaborated strengthening method for foundation bolt of motor and how to solve the problem of motor vibration with the six-point positioning principle. This method has been validated through field practices, which could effectively prevent and solve the problem of unnatural vibrations for dust removing fan.

With the incremental production of small size products, coil shape control gradually becomes the key link to restrict quality and benefits. The defective coil shape not only affects operation rate and economic and technical indexes of high speed wire rod production, but also causes such problem as there are troubles in the process of using wire for downstream users so that the efficiency of downstream processing is affected. In this paper, it is analyzed some factors affecting the spinning state of wire rod in high speed wire rod production line, briefly elaborated several cases of defective coil shape in production process, analyzed causes of problems and proposed solutions so as to improve the production efficiency and quality of product. The regular coil shape could ensure smooth wire and reduce rate of fracture of wire for drawing of users so that the quality improvement in the whole process is realized.

The heating in smelting and rolling laboratory is with natural gas radiation as well as the CO generated by natural gas leakage and incomplete combustion can lead to such accidents as fires and explosions very easily. In the article, a wireless and low-cost detection system of flammable gas is developed, which is with the STM32F103 series single chip computer as main control system. The concentrations of methane and CO in workshop are monitored with MQ-2 and MQ-7 gas sensors, temperature and humidity in workshop are monitored with SHT30 sensor of temperature and humidity as well as the data collected by sensors is transmitted to mobile terminal with Bluetooth module. The data processing and analysis are realized with mobile terminal and Android operating system, which could meet the requirements of monitoring flammable gas used in smelting and rolling laboratory.