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, 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 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.

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 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 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 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 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.

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.