In the production process of 2 250 mm hot continuous rolling band steel, there would be a large number of warp defects at edge of low carbon steel. In order to reduce or avoid the occurrence of warp defect, its causes are analyzed from its morphology, the relation between generation of warp and edging draught of vertical roll of roughing mill, time in furnace and tapping temperature of slab as well as control of Mn/S for composition of slab. Finally, the corresponding countermeasures are formulated so that the occurrence rate of warp defect is reduced.

In the paper, the particle size distribution of blended coal is optimized according to the quality indexes of blended coal with different granularity compositions through analyzing properties of blended coal for tamping coking of Baotou Steel with different particle sizes so that standard deviation of granularity composition for blended coal gradually reduces. In addition, the selective comminution of hard coal is carried out through selective precomminution technology so that the quality of blended coal is stabilized. On the premise of ensuring stability of coal cake, 1/3 proportion of coking coal and gas coal is improved so that the consumption of high-quality coking coal and cost of blending coal reduce.

The Yangliugebu Iron Ore occurs in the amphibolite gneiss of Eastern pentamolecular formation of Seltengshan (rock) group in Neoarchean and the ore body is composed of magnetite quartzite. The amphibolite gneiss and magnetic anomaly are direct indicators for deposit. The iron ore in this area is with stronger magnetic properties, so it can be as an indirect indicator for deposit.

In this paper, the improvement is from the point of view of deformation process by increasing the number of roll in finished pass to form four-roll finished pass, increasing the constraint in direction of depth of rail and limiting free spread of rail surface so as to improve dimensional accuracy of depth of rail aiming at the existing problems in universal rolling of rail. The numerical calculation is performed using ANSYS/LS-dyna, deformation states in different conditions are analyzed, defects are amended so that the optimal solution is obtained. The better effects are obtained by applying it in production line of rail, fluctuation range of depth within the full length range of rail is reduced and defect of “high zone” caused by local depth fluctuation is solved so that the safety of running for high-speed train is improved.

As one of the important hot tools in perforated rolling process of seamless steel tube, the quality of guide plate directly affects quality and cost of steel tube. In this paper, the effects of modification of rare earth and heat treatment on carbide shape in high chromium nickel alloy guide plate are studied aiming at the problem of its fragmentation during use. Moreover, the microstructure of net carbide in high chromium nickel guide plate is fragmentated and broken, matrix structure is refined and carbide uniformly distributes by selecting reasonable process so that the purpose of improving service life of guide plate is achieved.

In order to improve the grade of iron concentrate and reduce the contents of other gangue minerals in iron concentrate, the concentration with wash mill is added after finely sieving in Concentration Plant of Baotou Steel. Moreover, such tests as feeding concentration of wash mill, magnetic field intensity, opening of water valve and bottom valve are carried out. Finally, the grade of iron concentrate increases from 56.8% to 67.0%, recovery rate of iron is 93.42% so that the effects of quality improvement and impurity reduction are achieved.

In this paper, the design and implementation processes of intelligent quality inspection system for scrap steel are mainly discussed. The system adopts such advanced intelligent technologies as artificial intelligence (AI), big data analysis and video capture to automatically analyze and grade the iron and steel scrap in storage so that such problems as inaccurate identification and unwarrantable objectivity caused by artificial quality inspection are solved. The system can be interconnected with the measurement system, settlement system and warehouse system to automatically generate settlement reports so that work efficiency can be greatly improved as well as safe, accurate and high-efficiency operation of scrap steel inspection is promoted.

Three-dimensional mathematical model is established with commercial software aiming at the tundish of slab caster to calculate flow field in tundish with different flow control device conditions of tundish as well as analyze the effects of different schemes on flow condition of molten steel and average retention time and the situations of inclusions in steel with adopting the optimization scheme. The results showed that the volume of dead zone for tundish reduced by 10.61% and the time that tracer appeared in tundish extended by 4.31% comparing the optimization scheme with original scheme, which are all beneficial to mixing molten steel in tundish as well as floating and removal of inclusions. Moreover, the level of inclusions in steel adopting optimization scheme could satisfy the requirements of production technology.

The ferric charge for tailings after carbonization reaction of steel slag is with magnetic separation, then the feasibility study of returning to sintering for concentrate powder and tail powder of magnetic separation is carried out. Their chemical components are analyzed and the effects of adding them into sintering process on content of P for molten iron of blast furnace are calculated. The effects of concentrate powder of magnetic separation on the sintering components and indexes are analyzed through its sinter pot test. Finally, it is proved that the concentrate powder of magnetic separation can return to sintering process to be used.

In the paper, it is introduced the new steel grade 30MnCr25RE is developed for manufacturing L80-1 grade oil casing based on the performance features of hardening and tempering L80-1 grade oil casing manufactured with original steel grade 30MnCr22 by studying the effects of alloy elements in steel. The industrial casual inspection results showed that the minimum yield strength was 570 MPa and maximum yield strength was 625 MPa as well as its fluctuation range was controlled within 55 MPa for L80-1 grade oil casing manufactured with new steel grade 30MnCr25RE. Compared with the original steel grade 30MnCr22, the fluctuation range of yield strength for developed new steel grade is narrower and its performances are more stable. Moreover, the elongation increases by about 4 percentage points comparing with that of L80-1 grade oil casing manufactured with original steel grade 30MnCr22 as well as the impact energy at 0 ℃ could meet the requirements of API spec 5CT technical specification and rigorous technical requirements of users.