CITIC Heavy Industries Co.
CITIC Heavy Industries Co.
Pan L.,CAS Institute of Mechanics |
Wei X.,CAS Institute of Mechanics |
Peng Y.,CITIC Heavy Industries Co. |
Ma Y.,Beijing University of Civil Engineering and Architecture |
Li B.,CAS Institute of Mechanics
Applied Thermal Engineering | Year: 2017
Sinter cooling is an important process in the sinter production process. This article analyses the sinter cooling procedure in a new vertical cooling device. The analysis model is established to study the pressure drop and the heat transfer and is used to analyse several conditions. The results show that the analysis model is reliable for predicting the operational parameters and achieving the preliminary projected dimension. The parameters such as the cooling air temperature and the cooling air superficial velocity non-uniformly vary along the cooling device. When the cooling device diameter is set as an independent variable, the normal volumetric flow rate is not related to the cooling device diameter. The cooling time increases with the increase in cooling device diameter, whereas the sinter layer height is negatively correlated to the cooling device diameter. When the sinter flow rate is set as an independent variable instead of the cooling device diameter, the cooling time decreases, whereas the sinter layer height increases with the increasing sinter flow rate. Both cooling time and sinter layer height decrease with the increase in hot sinter temperature. Importantly, the pressure drop is minimal with variation of the hot sinter temperature. © 2017 Elsevier Ltd
Yang Y.,Central South University |
Ye C.,Central South University |
Zou S.,CITIC Heavy Industries Co.
Jixie Qiangdu/Journal of Mechanical Strength | Year: 2017
Based on the of theory heat conduction and thermal-elasticity, simulated the braking process of mine hoist. The changing laws of the boundary condition on the brake disc's surface during braking were analyzed and the computing method of the convective coefficient was discussed emphatically. According to variable material properties and the actual dimension of brake disk, a 3-dimensional cycle-symmetric model of brake disk in mine hoist was established and the temperature and thermal stress distribution was researched under the different braking conditions. The article discussed the calculation method considering thermal stress, and analyzed and compared each method's advantage with disadvantage. The results indicate that the temperature and stress distribution of brake disk are closely related to the braking initial velocity and braking acceleration. The simulation provides an important reference for the optimization of lifting speed and braking acceleration, and the design and development of high-performance brake system. © 2017, Editorial Department of JOURNAL OF MECHANICAL STRENGTH. All right reserved.
Chen J.,Henan University of Science and Technology |
Feng W.,Henan University of Science and Technology |
Zhao Y.,CITIC Heavy Industries Co.
Protein Expression and Purification | Year: 2017
17β-hydroxysteroid dehydrogenase type 1 (17β-HSD1) mainly catalyzes the reduction of estrone into estradiol. The enzymatic conversion is a critical step in estradiol accumulation in breast tissue, which is a valuable prognosis index of breast cancer disease. However, the source of 17β-HSD1 for inhibitor design is limited. In this study, the fragment encoding human 17β-HSD1 was successfully cloned and expressed in human embryonic kidney (HEK) 293T mammalian cells. The recombinant protein was purified by immobilized metal ion affinity chromatography yielding above 17 mg of purified 17β-HSD1 protein per liter of cell culture, with a specific activity of 8.54 μmoL/min/mg of protein for conversion of estradiol into estrone, with NAD+ as cofactor at pH 9.2. Enzyme characterization studies revealed that the protein has estrogenic activity and the Km value for estrone is about 20 nM. The recombinant protein purified from transfected HEK293T cells had higher specific activity compared to that of the enzyme purified directly from placenta. The present data show that the mammalian cell expression system can provide active 17β-HSD1 which is functionally identical to its natural counterpart and easy to purify in qualities suitable for its structure-function study. © 2017 Elsevier Inc.
Li W.,Tsinghua University |
Shen B.,CITIC Heavy Industries Co. |
Shen H.,Tsinghua University |
Liu B.,Tsinghua University
IOP Conference Series: Materials Science and Engineering | Year: 2012
The paper presents the recent progress made by the authors on modelling of macrosegregation in steel ingots. A two-phase macrosegregation model was developed that incorporates descriptions of heat transfer, melt convection, solute transport, and solid movement on the process scale with microscopic relations for grain nucleation and growth. The formation of pipe shrinkage at the ingot top is also taken into account in the model. Firstly, a recently proposed numerical benchmark test of macrosegregation was used to verify the model. Then, the model was applied to predict the macrosegregation in a benchmark industrial-scale steel ingot. The predictions were validated against experimental data from the literature. Furthermore, macrosegregation experiment of an industrial 53-t steel ingot was performed. The simulation results were compared with the measurements. It is indicated that the typical macrosegregation patterns encountered in steel ingots, including a positively segregated zone in the hot top and a negative segregation in the bottom part of the ingot, are well reproduced with the model. © Published under licence by IOP Publishing Ltd.
You M.,CITIC Heavy Industries Co.
Zhuzao/Foundry | Year: 2014
The wire feeding production process of ductile iron grinding table with a gross weight of 95 t was introduced. The microstructure and mechanical properties, ultrasonic and testing magnetic particle all meet the technical requirements of the casting. Meanwhile, mass production achieves with a steady quality up to now. The production practice shows that wire feeding process is an effective way to produce large ductile iron castings.
Yue Z.-G.,CITIC Heavy Industries Co. |
Gao X.-Y.,CITIC Heavy Industries Co.
Zhuzao/Foundry | Year: 2016
Shrinkage, dispersed shrinkage and crack of R zones easily occurred in head casting of mine mill causes during casting process. By reasonable designing of riser, pad, chills and pouring system, the defects above were avoided. The quality of head is good to meet the UT and MT requests. © 2016, Chinese Mechanical Engineering Society. All right reserved.
Li R.,Xuchang University |
Ding R.,Xuchang University |
Wang F.,CITIC Heavy Industries Co.
Jixie Gongcheng Xuebao/Journal of Mechanical Engineering | Year: 2011
A novel four phase translational meshing motor with double rotors is presented, and each magnetic pole of new motor consists of one stator, one internal and external rotors. Four internal rotors of magnetic poles are fixed together as one four-pole internal translational rotor and four internal rotors are fixed together as one four-pole external translational rotor. If controlling electromagnetic force of magnetic poles, the internal and external translational rotors move opposite direction synchronously by circle translation with the restricting of eccentric shafts mechanism, meanwhile, it drive internal ring gears meshing with external gears to output big torque with the elimination of inertia force and the increases of output torque. The prototype is found, and the flux linkage characteristic is calculated through finite element method. In additional, the static torque is computed utilizing the magnetic coenergy principle. The characteristics of speed and torque are acquired form prototype experimental results. Compared with the driving device of traditional motor and reducer, the double rotors translational meshing motor is a feasible translational motor with features of rapid start, high efficiency and big output torque. © 2011 Journal of Mechanical Engineering.
Chunlei G.,University of Science and Technology Beijing |
Yongdong X.,CITIC Heavy Industries Co. |
Mengjun W.,Central South University
Materials Science and Engineering A | Year: 2011
Isothermal compression tests were carried out on Al6061 using a Gleeble-1500 thermal simulator at temperatures ranging from 573 to 723K and strain rates from 0.5 to 30s-1. The flow stress of Al6061 was characterized based on an analysis of the true stress-true strain curves. A mathematical mode coupling flow stress with strain, strain rate and temperature for Al6061 has been proposed by using a hyperbolic sinusoidal type equation. The material constant α is 0.01MPa-1 in the model, whereas other material constants n, lnA and Q are found to be functions of strain. The predicted results from this proposed model are found to be in good agreement with the experimental flow stress curves which can be used to predict the required deformation forces in hot deformation processes. © 2011 Elsevier B.V.
Luoyang Mining Machinery Engineering Design And Research Institute Co. and CITIC Heavy Industries Co. | Date: 2013-02-28
The invention provides a system for calcining active lime, including a precalcining furnace for receiving limestone materials to be calcined and precalcining the limestone materials, and a rotary kiln for receiving the materials containing precalcined product from the precalcining furnace, outputting the formed active lime, and at the same time supplying a first flue gas to the precalcining furnace. The calcining system further includes a precalcining furnace combustion device, which generates a second flue gas and supplies it to the precalcining furnace, such that the limestone materials are precalcined in the precalcining furnace under the action of the first flue gas and the second flue gas. In this way, the precalcining rate of the limestone materials in the precalcining furnace is significantly improved. Since the heat exchange in the precalcining furnace is mainly in the form of convective heat exchange having a high heat efficiency, the heat exchange efficiency of the whole system is improved, and thus the heat consumption of the system is reduced.