The stability of rock slopes is mainly controlled by the spatial composing relations between the developmental structural plane in slope rock mass and slope. The stereographic projection is to project the interaction cutting relation of slopes and structural plane space onto a plane, with which the failure types and stability of rock slopes could be intuitively and preliminarily analyzed to provide support for the subsequent treatment of rock slopes. The analysis and determination for failure types and stability of rock slopes with polar stereographic projection are introduced by taking the stability evaluation of rock slope for 2^# open pit of Shuangli Iron Mine of Inner Mongolia Shuangli Mining Co. , Ltd. as an example as well as the prevention measures for unstable rock slope are proposed based on the failure types of slopes.

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.

The comparison tests for corrosion resistances of samples with and without black spots on the surface of Zn-Al-Mg coating as well as the pure Zn coating are carried out with the neutral salt spray tests. There was not red rust for the samples with and without black spots on the surface of Zn-Al-Mg coating with the neutral salt spray tests of 2 000 h and 4 000 h, while there was obvious red rust for the sample with pure Zn coating with the test of 2 000 h and it was increased obviously with the test of 4 000 h. The positions with and without black spots of Zn-Al-Mg coating are analyzed with the scanning electron microscope and energy disperse spectroscopy. The results showed that many fine magnesium-rich eutectic structures were enriched at the position with black spots. There were differences for reflection of light between them and stripy eutectic structure at the position without black spots as well as the magnesium-rich eutectic structures were easily to be oxidized by the oxygen in the air so as to form black oxide so that the visual differences appear black spots. The salt spray test results showed that the corrosion resistance at the position with black spots didn’t deteriorate as well as the corrosion resistances of samples with and without black spots on the surface of Zn-Al-Mg coating were the same good.

In this paper, it is mainly introduced the influencing factors and control main points of the resistance to hydrogen sulfide stress corrosion for oil casing. In order to meet the usage requirements of high strength oil casing resistant to hydrogen sulfide corrosion, the oil casing resistant to hydrogen sulfide with independent intelligent property rights is manufactured through selecting Cr, Mo, and Ti as the main corrosion resistant alloy elements, strictly controlling contents of S and P as well as reasonably optimizing microalloy elements. Its impact absorbing energy at 0 ℃ reaches over 100 J, so it is with both high strength and toughness as well as they match reasonably so that it is with good resistance to hydrogen sulfide corrosion.

The 5th generation American Morgan technology was introduced in the early 1990s for a production line of high speed wire rod and its design capacity was 0.38 million tons. With the constant improvement of production technology and efficiency for the deep processing industry of wire rod, the requirements of dimensional accuracy, surface quality and mechanical properties for wire products in the market are higher. In order to satisfy the market changes and improve product competitiveness, the size reducing mill is added in the production line of high speed wire rod. In the paper, it is introduced the construction transformations of such types of equipment as mechanical, electrical and power as well as the roll gaps of finishing rolling unit and size reducing mill are redesigned. Moreover, the R values of each stand are given as well as different accident types and solutions after the mill put into production are summarized.

In this paper, the oxidation and decarbonization as well as formation rule of heterogeneous particles around cracks of web for SS400B hot rolled H beam are studied. The experiment is designed based on the actual working conditions on site as well as oxidation and decarbonization and performance distribution of heterogeneous particles with different processes are analyzed qualitatively and quantitatively with metallographic analysis and energy spectrum. The results showed that there was decarburization around cracks of SS400B hot rolled H beam in the stage of rough rolling, but no heterogeneous particles appeared. It is systematically and comprehensively explained that the oxidation and decarbonization and precipitation of silicon containing heterogeneous particles around cracks are closely related to the composition of steel, process location and thermal regulation combining with domestic study results.

The chemical composition of wire rod for 2 200 MPa ultra-high strength steel strand is designed based on the chemical composition of SWRH82B. The Φ14 mm wire rod is rolled by second heating and cogging with 280 mm×380 mm continuous casting billet. The tensile strength of hot rolled wire rod is increased from 1 150 MPa to over 1 450 MPa by optimizing the cooling rate of wire rod. The target that the strength of steel strand reaches over 2 200 MPa after drawing is realized. The results of industrial trial production showed that the time of soft blow and deep vacuum was the key to control the size of non-metallic inclusions and oxygen content in steel as well as it should be more than 15 min; under the condition of constant casting speed and the degree of superheat is below 35 ℃, the center macrosegregation index could be controlled below 1.15; the ideal microstructure of sorbite could be obtained by controlling moderate cooling rate and optimum cooling rate was 4.89~5.62 ℃/s.

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.