电解铝用新型阳极钢爪

阳极钢爪是铝电解生产中预焙阳极的重要构件,主要作用是连接阳极炭块并向电解槽传输电流,其导电性能的优劣和使用寿命很大程度影响电解铝生产的电耗和经济效益。目前,阳极钢爪均以废钢为原料,采用消失模铸造生产,易产生化学成分不稳定、电阻率高、抗氧化性差等缺陷。新型阳极钢爪的材料为低碳钢,钢爪横梁使用热轧厚板,按照钢爪横梁尺寸进行切割,钢爪腿材料选择轧制圓棒,采用特种熔焊工艺将钢爪腿与钢爪横梁熔焊,实现全截面的冶金结合。国内电解铝企业使用结果表明:新型阳极钢爪较普通铸造钢爪导电性和抗氧化性有一定提高,可以更好地满足电解铝生产的要求。     

技术成果

电解铝阳极钢爪修复难题攻克2012年9月19日,由江西世星新材料科技有限公司等联合研发的"电解铝阳极钢爪熔渣池熔焊再制造技术"项目,在江西南昌通过由中国有色金属工业协会组织的科技成果鉴定。电解铝阳极钢爪修复,是长期困扰电解铝企业的重大技术难题。在生产过程中,钢爪腿由于受高温电解液腐蚀而逐步变细,而横梁主体部分通常保     

抗氧化防腐涂料在预焙阳极铝电解槽上的应用

主要介绍了抗氧化防腐涂料在400 kA系列预焙阳极铝电解槽预焙阳极及钢爪表面上涂刷(或喷涂)应用,分析、验证抗氧化防腐涂料对预焙阳极及钢爪的抗氧化防腐效果。结果表明,阳极抗氧化防腐涂料具备良好的抗氧化性,刷涂抗氧化防腐涂料的阳极,无阳极氧化和阳极钢爪被氧化和侵蚀现象,可延长阳极换极周期至少1天以上。     

铝电解阳极导杆钢爪清理机的改进与设计

结合本单位阳极组装生产线上钢爪清理机的实际应用,针对已使用过的清理阳极导杆组钢爪表面的抛丸机和钢丝清刷机两种机械存在的缺陷,提出应用钢丝绳清理机这一新型设备清理钢爪表面。文章介绍了新型清理机的结构形式、工作原理及其使用效果。     

铝电解阳极组装系统自动控制新技术研究

针对铝电解阳极组装系统存在阳极炭块浇铸生产力低、炭块钢炭压降高、阳极钢爪氧化层清理难度大等工程技术问题,开发出钢爪氧化铁自动清理、残极电解质全自动清理及单悬链系统双小车控制等新技术,实现了阳极钢炭压降≤75 mV、阳极浇铸处理能力70颗/h、阳极底掌电解质清理能力75颗/h等目标,解决了设备故障,提升设备自动化控制水平。     

阳极导杆与阳极钢爪的连接结构

本发明涉及一种阳极导杆与阳极钢爪,尤其涉及一种在预焙阳极电解槽中阳极导杆与阳极钢爪的连接结构。阳极导杆与阳极钢爪的连接结构,包括阳极导杆,和与阳极导杆连接的阳极钢爪,阳极导杆与阳极钢爪之间浇注磷铁连接,在阳极导杆的下部设有孔,在阳极导杆下部的四周设有钢板,钢板上没有销轴孔.     

电解铝用阳极钢爪浸蘸石墨模式的新探索

针对电解铝用阳极钢爪浸蘸石墨传统模式存在的不足,进行分析、探索和改进,研发了新的模式,解决了石墨粉不能均匀涂在钢爪表面的问题,对降低磷铁压降、利于钢爪与磷铁分离以及保护钢爪不受铁水侵蚀起到非常重要的作用.     

技术成果

阳极导杆与阳极钢爪的连接结构专利申请号:CN200810229268.7公开号:CN101748439A申请人:沈阳铝镁设计研究院本发明涉及一种阳极导杆与阳极钢爪,尤其涉及一种在预焙阳极电解槽中阳极导杆与阳极钢爪的连接结构。阳极导杆与阳极钢爪的连接结构,包括     

铝电解槽新型阳极钢爪研究

为进一步降低电解槽工作电压,本文提出一种新型的阳极钢爪结构。利用有限元软件ANSYS模拟了铝电解槽单阳极的热-电耦合模型,分析比较了新型阳极钢爪与传统钢爪对阳极压降的影响,并与实际试验结果进行了对比。结果表明该新型阳极钢爪的电压降更低,钢爪出口的电流均匀性更好。     

华鹭铝业消失模铸造技术试制成功

日前，华鹭铝业自主开发研制的导杆横梁钢爪铸造制作消失模铸造新技术试制成功。华鹭铝业组装部针对公司阳极炭块生产所需导杆相对紧缺、导杆钢爪及导杆横梁消损严重的问题，在充分考虑中频炉化铁优势的前提下，组织开展消失模铸造的技术论证、图纸设计、学习考察等工作，完成设备的安装和调试，并实现了一次试车成功。消失模铸造新技术充分利用原有的闲置设备和厂房，投资小、见效快，每年节约委托加工电解系统导杆横梁的费用达10万元以上，     

不同显微结构Yb2Si2O7环境障涂层的抗热震性能研究

采用低压等离子喷涂工艺(LPPS)在SiCf/SiC复合材料表面依次制备了Si底层、Mullite中间层和Yb2Si2O7面层的环境障涂层.通过不同的喷涂参数分别制备出层状结构和层柱混合结构的Yb2Si2O7面层,并考察面层结构对环境障涂层抗热震性能的影响.结果表明,所制备的两种面层涂层均具有孔隙率低、界面结合紧密的特...     

Testing and Modeling of a New Moment Connection of Concrete-Filled FRP Tubes to Footings under Monotonic and Cyclic Loadings

This study explores a new moment connection of concrete-filled fiber-reinforced polymer (FRP) tube (CFFT) to concrete footing. The tube is tightly fitted and adhesively bonded to a short reinforced concrete stub protruding from the footing, which facilitates concrete filling of the tube without the need for shoring. To establish the critical stub length (Xcr), specimens with heavily steel-reinforced stubs varying in length from 0.5D to 2.0D, where D = diameter of the CFFT, were fabricated and tested in flexure by using a cantilever setup. The Xcr required to achieve flexural failure of the CFFT was 1.05D. Additional specimens with a sufficient stub length of 1.5D were then fabricated to examine the effect on strength and ductility of the steel reinforcement ratio (ρs) in the stub. The optimal ρs of the stub required for the CFFT to reach flexural failure was 3.2%. Finally, the effect of low-cycle reversed bending fatigue was studied with and without an axial compression load. Remarkable ductility associated with the formation of a plastic hinge was observed at ρs of 2%. An analytical model capable of predicting (1)?moment capacity of the connection, (2)?whether failure is governed by flexure or bond, and (3)?Xcr was developed and validated. It was then used in a parametric study to explore the effects of CFFT mechanical and geometric properties on Xcr.     

济钢4#连铸机振动发生装置技术改造

针对4#连铸机快速更换台振动发生装置原设计存在的不足,将偏心轴轴头直径由75mm加大为110mm,轴头根部过渡圆角半径由1.6mm改为6mm,经强度校核分析,偏心轴的安全系数增加为原来的3.15倍;同时改造中心减速机的安装位置,消除万向联轴器的轴线夹角;采用双螺母和外侧螺母焊固的螺栓紧固方法.改造后,消除了快速更换台的各种故障,使用寿命由800炉提高到1000炉.     

RECOVERY OF CLEAN COAL FINES THROUGH A COMBINATION OF GRAVITY CONCENTRATOR AND FLOTATION PROCESSES

Flotation feed is a mixture of coarse and ultra-fine fractions. During conditioning of the flotation feed with collector and frother, the finer fraction consumes more reagents as compared to coarser particles. This is mainly due to more specific surface area of the ultra fine than the coarse fraction. This favors the adsorption of reagents toward ultra-finer fractions leads to less complete surface coverage of coarse particles and more entrainment of finer gangue particles. This results in the lower yield of coarse fractions from the flotation circuit and loss in selectivity. Hence, the major challenge is to improve the recovery of the coarser fraction and selectivity of ultra-fine fractions by improving flotation kinetics of all size fractions. This article deals with an approach to overcome the improper reagent adsorption by fine and coarse coal fractions in the flotation circuit through an innovative washing circuit containing gravity operation and flotation processes. Flotation performance between a new washing circuit having stub cyclone and flotation and normal single-stage reagent addition flotation process is compared in terms of selectivity, separation efficiency, rate constant, and size-wise recovery. The washing circuit having stub cyclone and flotation processes improves the fine clean coal yield by 10% and reduces the consumption of reagent compared to the normal single-stage reagent addition flotation process.     

Study on the Anode-to-Cathode Distance in an Aluminum Reduction Cell

A two-dimensional (2D) finite element model (FEM) of an anode immersed in an aluminum reduction cell was developed to study the initial current distribution in the anode as a function of anode geometry and electrical anode conductivity gradients. The numerical results of the initial state of the anode electrical current were used to describe analytically how this will affect the variation in the anode-to-cathode distance (ACD) in a steady-state scenario after several hours in the electrolysis bath. The electrical power loss in the anode has also been studied at different anode geometries and material properties. The slot positioning, slot depths, and stub hole dimensions have been considered in the FEM. The anode is implemented as an inhomogeneous orthotropic material with a defined six-parameter equation. The degree of initial inhomogeneous anode current density, which is expressed with a defined parameter k ₀, can reach values to cause variations in the ACD typically measured in the aluminum industry. To avoid a variation in the ACD for this case, the defined bath conductivity relation n should be within certain limits for the analyzed industrial reduction cell. The lowest degree of initial inhomogeneous current in the anode is achieved with deeper slots closer to each other and with an electrical current entering the anode in the bottom of the anode stub hole.     

Investigation on the Hydroforming Characteristics of Double‐layered Tubes

Double‐layered tubes consist of an inner tube and an outer tube. Both are similar in material, contact closely and deform simultaneously when subjected to external force. Hydroforming assembly technology has several advantages in the manufacturing of double‐layered tubes. In this study, the hydroforming characteristics of double‐layered tube are investigated. Free bulging tests are performed to produce formability diagrams of double‐layered tubes at various forming pressures and feeding amounts. In addition, the hexagonal‐shape hydroforming test is performed to estimate the dimensional accuracy of double‐layered tubes through the corner filling ratio and the gap between the inner and outer tubes. Besides experimental analyses, an analytical model that can predict internal pressure for the hydroforming of double‐layered tubes is proposed and experimentally validated in this study.     

Trypanosoma evansi in capybara from Venezuela

Twenty-nine strains of yeasts, which are capable of using galactose, melibiose, or raffinose, were screened for alpha-galactosidase production. Among the strains, 5 produced intracellular and extracellular alpha-galactosidases, and 2 produced only intracellular enzyme. Substrate specificities of these enzymes were explored using 6(3)-alpha-D-galactosyl-1,4-beta-D-mannotriose and 6(3)-alpha-D-galactosyl-1,4-beta-D-mannotetraose. All enzymes liberated the terminal galactose from 6(3)-alpha-D-galactosyl-1,4-beta-D-mannotriose, but did not the stub galactose from 6(3)-alpha-D-galactosyl-1,4-beta-D-mannotetraose.     

雾化轴承钢粉制造滚动轴承的研究

研究了用水雾化轴承钢料头、车屑制造滚动轴承套圈的工艺过程,研究了粉末中含氧量的控制及影响。测试了各项机械、物理性能。进行了接触疲劳、轴承寿命试验。其材料利用率为70%以上,外圈寿命为计算寿命的3倍。采用本工艺可以生产圆锥滚子轴承外圈。     

A theoretical analysis for the formation of periodic layered structure in ternary diffusion couples involving a displacement type of reactions

Periodic layered structures were found to form in numerous ternary diffusion couples of the type B_δ′C/A involving a displacement type of reactions. In all of these couples, A is a dominant diffusing species within the diffusion zone and C is essentially immobile. Occurrence of this type of layered structure was rationalized in terms of thermodynamic arguments. Moreover, a diffusion model was formulated to describe the growth of this structure. An appropriate solution to the diffusion equations was obtained when simplified assumptions were made. The relative stability of a periodic layered structure versus that of a simple layered structure is governed by the relative mobilities of A and B within the diffusion zone. The simple layered structure is formed when B has a high mobility relative to that of A. On the other hand, with increasing mobility of A, the periodic layered structure tends to be stable.     

热水锅炉分层燃烧技术的应用

针对锅炉煤层燃烧特点，采用了分层燃烧新技术，提高了燃烧效率。