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Force Analysis and Curve Design for Laying Pipe in Loop Laying Head of Wire Rod Mills
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作者 Shuangji Yao Marco Ceccarelli +1 位作者 Giuseppe Carbone Bin Ma 《中国机械工程学报:英文版》 SCIE EI CAS CSCD 2019年第2期36-52,共17页
Laying head is a high-precision engineering device in hot-rolled high speed wire rod production line. Previously research works are focused on the laying pipe wear-resisting. Laying pipe curve design method based on w... Laying head is a high-precision engineering device in hot-rolled high speed wire rod production line. Previously research works are focused on the laying pipe wear-resisting. Laying pipe curve design method based on wire rod kinematics and dynamics analyses are not reported before. In order to design and manufacture the laying pipe, the motion and force process of the wire rod in the laying pipe should be studied. In this paper, a novel approach is proposed to investigate the force modeling for hot-rolled wire rod in laying pipe. An idea of limited element method is used to analysis and calculates the forces between laying pipe inner surface and wire rod. The design requirements of laying pipe curve for manufacturing are discussed. The kinematics and dynamics modeling for numerical calculation are built. A laying pipe curve equation is proposed by discussing design boundary conditions. Numerical results with di erent laying pipe curves design parameters are plotted and compared. The proposed approach performs good result which can be applied for laying pipe curve design and analysis for engineering application. 展开更多
关键词 WIRE ROD MILLS LAYING head LAYING PIPE CURVE design WIRE ROD force analysis
一种基于PLC的送线装置控制系统设计 预览
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作者 官春平 《广东交通职业技术学院学报》 2019年第1期36-39,44共5页
针对目前耳机线加工过程存在送线效率低下、劳动强度大、通用性差等弊端,提出一种自动送线装置,介绍了其工艺动作与具体结构,设计了该装置的控制系统,重点阐述了其控制系统,开发了该自动送线装置。该装置包括启停机构、检测机构、线架... 针对目前耳机线加工过程存在送线效率低下、劳动强度大、通用性差等弊端,提出一种自动送线装置,介绍了其工艺动作与具体结构,设计了该装置的控制系统,重点阐述了其控制系统,开发了该自动送线装置。该装置包括启停机构、检测机构、线架以及自动控制系统,该控制系统采用上位机触摸屏、下位机PLC以及变频器相结合的控制方式,能实现高效送线、线速可调等功能,为相关行业电线自动化加工提供了推广、参考以及实用价值。 展开更多
关键词 线材 送线 自动控制 PLC
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Optimal use of fielder XT guidewire enhances the success rate of chronic total occlusion percutaneous coronary intervention 预览
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作者 Qian-Cheng Wang Hai-Ruo Lin +8 位作者 Yuan Han Hai Dong Kai Xu Shao-Yi Guan Zhen-Huan Chen Hui-Xin Hao Jian-Ping Bin Yu-Lin Liao Quan-Min Jing 《世界临床病例杂志》 2019年第8期928-939,共12页
BACKGROUND Chronic total occlusion (CTO) is found in 18-31% of patients who undergo coronary angiography. Successful recanalization of CTOs is associated with reduced recurrent angina pectoris rates and increased long... BACKGROUND Chronic total occlusion (CTO) is found in 18-31% of patients who undergo coronary angiography. Successful recanalization of CTOs is associated with reduced recurrent angina pectoris rates and increased long-term survival. Although the success rate of CTO percutaneous coronary intervention (CTO-PCI) has improved, CTO-PCI remains technically challenging. The Fielder XT guidewire was designed for CTO lesions. To validate whether the use of the guidewire increases the success rate, we compared the results of CTO-PCI with or without the guidewire. We hypothesized that the use of Fielder XT guidewire can increase the success rate of CTO-PCI. AIM To investigate whether the use of Fielder XT guidewire increases the final procedural success of CTO-PCI via the anterograde approach. METHODS Between January 2013 and December 2015, a retrospective study was conducted on 1230 consecutive patients with CTO who received PCI via the anterograde approach at the General Hospital of Northern Theater Command. The patients were divided into an XT Group (n = 686) and a no-XT Group (n = 544) depending on whether Fielder XT guidewire was used. Both groups were compared for clinical parameters, lesion-related characteristics, procedural outcomes and in?hospital complications. The data were statistically analyzed using Pearson’s χ 2 test for categorical variables, and Students’ t test was used to compare the quantitative data. Significant independent factors and a risk ratio with 95% confidence interval (CI) were assessed by multivariate logistic regression analysis. RESULTS In total, 1230 patients were recruited;75.4% of the patients were male, and 55.8% of the patients were in the XT group. The overall success rate was 83.9%, with 87.8% in the XT group. Based on multivariate logistic regression analysis, factors positively associated with procedural success were the use of Fielder XT guidewire (P = 0.005, 95%CI: 1.172-2.380) and systolic blood pressure (P = 0.011, 95%CI: 1.003-1.022), while factors negatively associated w 展开更多
关键词 Chronic total OCCLUSION Percutaneous coronary intervention ANTEROGRADE WIRE ESCALATION Parallel WIRE technique Fielder XT GUIDEWIRE Success rate
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Effect of wire tension on different output responses during wire electric discharge machining on AISI 304 stainless steel 预览
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作者 Tina Chaudhary Arshad Noor Siddiquee Arindam Kumar Chanda 《Defence Technology(防务技术)》 CAS CSCD 2019年第4期541-544,共4页
WEDM is used in machining conductive materials where it is required to obtained complicated and intricate shapes with high accuracy.Various applications are in the field of automobile,medical industries,aerospace etc.... WEDM is used in machining conductive materials where it is required to obtained complicated and intricate shapes with high accuracy.Various applications are in the field of automobile,medical industries,aerospace etc.WEDM is an economical machining option with short product development cycle.Surface roughness,kerf width,Material removal rate,Recast layer hardness and surface microhardness in WEDM are most important responses.In this paper,effect of varied Wire tension on SR,KW,MRR,RCL hardness and surface microhardness on AISI 304 have been investigated.Pulse on time,pulse off time,current and dielectric fluid are taken as fixed parameter.Results show that Wire tension influences the SR,MRR and Surface microhardness and has no effect on kerf width in case of Stainless steel304. 展开更多
关键词 WIRE EDM WIRE tension Material removal rate Surface ROUGHNESS KERF WIDTH Micro-hardness
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电线电缆柔软性定量测试方法探讨
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作者 吉玉玲 张晋 王海玉 《光纤与电缆及其应用技术》 2019年第5期10-13,23共5页
针对目前国内外电线电缆领域对于电线电缆柔软性的定量测试需求,深入探讨了标准GB/T 4074.3—2008和EN 3475-704中与电线电缆柔软性相关的测试方法,比较了两个标准中测试方法的优缺点及适用范围。标准GB/T 4074.3—2008中测试方法适用... 针对目前国内外电线电缆领域对于电线电缆柔软性的定量测试需求,深入探讨了标准GB/T 4074.3—2008和EN 3475-704中与电线电缆柔软性相关的测试方法,比较了两个标准中测试方法的优缺点及适用范围。标准GB/T 4074.3—2008中测试方法适用于表征线缆的屈服应力,不适于表征电缆的柔软性。标准EN 3475-704中测试方法更适于电线电缆柔软性的测试,测试方法1适合于大尺寸线缆柔软性的测试,柔软性的表征参数为电缆圆环(内径为40Dmax)压缩位移为10Dmax时的压缩力,测试方法2适合于小尺寸线缆柔软性的测试,柔软性的表征参数为使线缆弯曲90°所施加的载荷。通过分析标准EN 3475-704中测试方法,发现测试方法1受重力影响,具有一定测试缺陷,为此提出了通过采用将试样水平放置以有效避免重力的影响,并对测试方法1和测试方法2的各测试参数提出了公差范围的限定,以方便测试实施。 展开更多
关键词 电线 电缆 柔软性 测试 定量
Delta-doped quantum wire tunnel junction for highly concentrated solar cells
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作者 Ali Bahrami Mahyar Dehdast +1 位作者 Shahram Mohammadnejad Habib Badri Ghavifekr 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第4期275-279,共5页
We propose a novel structure for tunnel junction based on delta-doped AlGaAs/GaAs quantum wires. Higher spatial confinement of quantum wires alongside the increased effective doping concentration in the delta-doped re... We propose a novel structure for tunnel junction based on delta-doped AlGaAs/GaAs quantum wires. Higher spatial confinement of quantum wires alongside the increased effective doping concentration in the delta-doped regions extremely increase the peak tunneling current and enhance the performance of tunnel junction. The proposed structure can be used as tunnel junction in the multijunction solar cells under the highest possible thermodynamically limited solar concentration.The combination of the quantum wire with the delta-doped structure can be of benefit to the solar cells’ advantages including higher number of sub-bands and high degeneracy. Simulation results show a voltage drop of 40 mV due to the proposed tunnel junction used in a multijunction solar cell which presents an extremely low resistance to the achieved peak tunneling current. 展开更多
关键词 delta-doping quantum wire SOLAR cell TUNNEL JUNCTION
清梳关键器材应用分析与工艺平衡 预览
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作者 谢家祥 《纺织器材》 2019年第2期14-21,共8页
为了减少纤维损伤以降低短绒从而提高纤维梳理质量,详细探讨清理器材和梳理器材的选配、使用维护和上机工艺;清理工序从自由打击到握持打击分析打手的型式、密度、形状、高度和排列方式,强调应注重清理纤维中的杂质、减小纤维损伤,并对... 为了减少纤维损伤以降低短绒从而提高纤维梳理质量,详细探讨清理器材和梳理器材的选配、使用维护和上机工艺;清理工序从自由打击到握持打击分析打手的型式、密度、形状、高度和排列方式,强调应注重清理纤维中的杂质、减小纤维损伤,并对打手进行改进;梳理工序从金属针布、弹性盖板针布两方面分析针布的材质、表面处理、尺寸规格参数、合理选配和维护保养。指出:锡林金属针布应穿刺能力强,握持和释放能力兼顾;刺辊梳理产生短绒最多,齿尖锋利度影响梳理质量;使用固定盖板不宜连续多于4根,宜选用斜纹式或横密式排列,避免形成纤维束'通路'而出现漏梳;棉精梳机锡林金属针布第1组的齿隙不宜过小,第2、3组齿密不宜相差过大,喂入纤维棉结太多会降低梳理质量;增大齿密、减小前角、变速梳理会加剧纤维的损伤,产生更多的短绒;顶梳的选配要与锡林金属针布相适应,回转盖板弹性针布采用变前角植针、弹性盖板针布与齿条盖板针布混用会提高梳理质量。 展开更多
关键词 打手 型式 金属针布 齿条 弹性针布 棉精梳机 锡林 顶梳 刺辊 回转盖板 梳理质量 梳理效能 平行控制
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金属熔丝增材制造技术的研究现状与展望 预览
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作者 王钰 王凯 +2 位作者 丁东红 卢清华 易江龙 《电焊机》 2019年第1期69-77,123共10页
随着现代计算机技术的快速发展,增材制造技术在诸多工业领域得到了广泛应用,逐渐成为智能制造技术的典型代表。其中,金属熔丝增材制造由于其成形效率高、成本低、材料利用率高等优势,已逐渐成为国内外增材制造研究的热点。介绍了金属熔... 随着现代计算机技术的快速发展,增材制造技术在诸多工业领域得到了广泛应用,逐渐成为智能制造技术的典型代表。其中,金属熔丝增材制造由于其成形效率高、成本低、材料利用率高等优势,已逐渐成为国内外增材制造研究的热点。介绍了金属熔丝增材制造技术的分类、应用范围、各自的优缺点和研究现状,重点讨论电弧熔丝增材制造技术的细分领域现状及应用,分析金属熔丝增材制造技术的未来研究目标与发展趋势。 展开更多
关键词 增材制造 丝材 金属材料 综述
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Thermodynamic study on welding wire design of high nitrogen austenitic stainless steel 预览
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作者 明珠 王克鸿 +2 位作者 屈天鹏 王伟 冯胜强 《中国焊接:英文版》 EI CAS 2019年第1期49-55,共7页
Based on thermodynamic calculations, the effect of pressure and alloying elements on the nitrogen content, solidification mode, and welding characteristics were investigated in this study. By increasing the partial pr... Based on thermodynamic calculations, the effect of pressure and alloying elements on the nitrogen content, solidification mode, and welding characteristics were investigated in this study. By increasing the partial pressure of N 2 , the nitrogen content in the weld pool increased dramatically, and the γ zone was enlarged. The nitrogen content increased as alloying elements such as Cr and Mn were added to the molten steel. The δ zone with high temperature treatment was compressed by adding Ni. These alloying elements play important roles in the formation of the single γ region at the temperature of 298 K. With proper Mn addition, the phase area of γ was extended and became more stable, and the “ferrite trap” was also avoided. Two kinds of welding wires with different nitrogen contents were developed and corresponding MIG welding experiments were performed. As the nitrogen content in wire was higher than that in the base metal, severe blowhole defects and mixture microstructure of δ and γ developed. 展开更多
关键词 high NITROGEN steel NITROGEN LOSS THERMODYNAMICS CALCULATION WIRE DESIGN
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A Principle of Producing Multi-ply Paper Using a Wire in an Inclined Wire Machine 预览
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作者 Song-Il Pak Yong-Il Ri Chol-Ho Kim 《造纸与生物质材料:英文版》 2019年第1期48-56,共9页
In this study,we improved the dispersibility of the stocks in the headbox of an inclined wire machine to produce a distinct paper,and analyzed some factors affecting paper formation in the production of multiply paper... In this study,we improved the dispersibility of the stocks in the headbox of an inclined wire machine to produce a distinct paper,and analyzed some factors affecting paper formation in the production of multiply paper.We used FLUENT6.3 to analyze the flow of the stocks in the headbox and select the structure of the diffusion part required for improving the dispersibility of fibers.Moreover,based on a simulation experiment,the optimal rational angle of the diffusion part(g)was found to be approximately 8°~10°,and it improved the paper formation in the case of usage of two plates.Using the equation for the formation of paper layers in the headbox of an inclined wire machine,we obtained a paper with the given basic weight by controlling the inclined angle of the wire(a),initial height of water(H),and concentration of the stocks.We considered the effect of a and H of the stocks in the headbox on the fiber distribution,and according to the results,a should be set as approximately 20°~30°and H should be maximally high.When producing multi-ply paper by a wire,the line pressure of the couch roll should be maintained at 1.8~2.0 kN/m to avoid the damage to the paper sheets.In addition,we found the optimal structure parameter of the dehydrated roll was as follows:hole ratio of approximately 30%of the dehydrated roll surface area,width of 1.5~2.0 mm,slot pitch of 5~6 mm,slot depth of 2~3 mm,and inclined angle of diffusion part(b)of 5°. 展开更多
关键词 inclined WIRE MACHINE HEADBOX fiber SUSPENSIONS fluid multiply PAPER PAPERMAKING
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低碳冷镦钢SWRCH8A冷镦开裂原因分析及改善措施 预览
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作者 寻忠忠 农之江 吴德兴 《山西冶金》 CAS 2019年第4期9-10,共2页
针对SWRCH8A线材在生产过程中发生开裂质量问题,对线材进行酸洗、金相及电镜能谱检测分析,分析表明该质量问题是由于钢坯表面卷渣造成的冷镦开裂质量问题。通过金相及电镜能谱检测分析查找造成冷镦开裂原因,提出了相应的改善冷镦钢质量... 针对SWRCH8A线材在生产过程中发生开裂质量问题,对线材进行酸洗、金相及电镜能谱检测分析,分析表明该质量问题是由于钢坯表面卷渣造成的冷镦开裂质量问题。通过金相及电镜能谱检测分析查找造成冷镦开裂原因,提出了相应的改善冷镦钢质量措施。 展开更多
关键词 SWRCH8A 线材 冷镦开裂 卷渣 缺陷
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Steerable microcatheters for complex percutaneous coronary interventions in octogenarians:from Venture to Swift Ninja 预览
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作者 George Kassimis Nestoras Kontogiannis Tushar Raina 《老年心脏病学杂志:英文版》 SCIE CAS CSCD 2019年第1期54-59,共6页
0ctogenarians represent the fastest growing group of patients undergoing percutaneous coronary intervention(PCI),now constituting more than one in five patients treated with PCI in real-world practice.[1,2]Comparing c... 0ctogenarians represent the fastest growing group of patients undergoing percutaneous coronary intervention(PCI),now constituting more than one in five patients treated with PCI in real-world practice.[1,2]Comparing coronary lesion characteristics of patients aged<≥80 years to those≥80 years undergoing PCI,the octogenarians have a higher prevalence of calcified and ostial lesions,tortuous coronary anatomy,multi-vessel disease and left main stem(LMS)stenosis.⑶Furthermore,they often have greater ischemic burden than their younger counterparts,suggesting an even greater benefit following revascularization. 展开更多
关键词 Acute ANGLE branch OCTOGENARIANS Steerable microcatheters Supercross SWIFT NINJA VENTURE wire control CATHETER
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离子流场模型中高压直流导线表面粗糙系数的表征方法
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作者 陈博 卢铁兵 +2 位作者 徐鹏 王东来 李学宝 《高电压技术》 EI CAS CSCD 北大核心 2019年第5期1443-1450,共8页
高压直流输电线路电晕放电会产生离子流场问题。裸露的导线受到风沙及摩擦磨损,导致表面粗糙度增加,更易发生电晕放电。因此,导线表面微观几何形态是影响直流输电线路离子流场的重要因素。为此,利用砂粒对导线表面进行处理,模拟风沙对... 高压直流输电线路电晕放电会产生离子流场问题。裸露的导线受到风沙及摩擦磨损,导致表面粗糙度增加,更易发生电晕放电。因此,导线表面微观几何形态是影响直流输电线路离子流场的重要因素。为此,利用砂粒对导线表面进行处理,模拟风沙对输电线路的影响,制备了粗糙度不同的导线样品。基于光切法,对导线样品表面微观几何形态进行了分析,得到了导线样品粗糙度。用有限元计算了不同表面微观几何形态的导线表面场强,当粗糙度增大时,导线表面最大场强增大,尖刺状凸起增多。并利用电晕笼测量获得了导线样品起晕电压,建立了导线表面粗糙度与Peek公式中粗糙系数的关联关系。随着粗糙度的增大,粗糙系数减小。进而将此关联关系应用于离子流场计算中,利用测量得到的表面粗糙度表征了粗糙系数,使得离子流场计算中对导线表面微观几何形态的表述更具科学依据。 展开更多
关键词 高压直流输电 导线 表面粗糙度 起晕电压 离子流场
温升作用下碳纤维增强复材绞线型拉索抗冲击性能的试验研究
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作者 方亚威 方志 蒋正文 《工业建筑》 CSCD 北大核心 2019年第9期6-9,共4页
为研究温度作用对碳纤维增强复合材料(CFRP)绞线抗冲击性能的影响,对4组CFRP绞线试件在20,40,60,80℃温度下进行了横向落锤冲击试验。结果表明:随着温度的升高,CFRP绞线的纵向裂纹长度降低;当温度由20℃升高至80℃,由于树脂基体的软化,C... 为研究温度作用对碳纤维增强复合材料(CFRP)绞线抗冲击性能的影响,对4组CFRP绞线试件在20,40,60,80℃温度下进行了横向落锤冲击试验。结果表明:随着温度的升高,CFRP绞线的纵向裂纹长度降低;当温度由20℃升高至80℃,由于树脂基体的软化,CFRP绞线在断裂时刻的侧向位移提高了22. 5%;由于温升作用降低了CFRP绞线内部的应力集中,促进了绞线内部应力的均匀分布,使得其最大纵向索力、最大冲击力和总吸收能量分别提高了4. 76%、19. 3%和43. 4%。 展开更多
关键词 碳纤维增强复材 绞线 温度效应 抗冲击性能
基于无人机巡检的输电线路规避系统设计 预览
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作者 石书山 谢璐 +1 位作者 周筑博 杨鹤猛 《电力大数据》 2019年第8期67-74,共8页
无人机进行输电线路巡检时,常常存在与输电线路发生碰撞的风险,为解决无人机巡线系统及输电线路运行安全存在的问题,本文对超声波传感器、激光雷达、毫米波雷达和双目摄像机等不同的障碍检测传感器进行指标性能分析,基于毫米波雷达传感... 无人机进行输电线路巡检时,常常存在与输电线路发生碰撞的风险,为解决无人机巡线系统及输电线路运行安全存在的问题,本文对超声波传感器、激光雷达、毫米波雷达和双目摄像机等不同的障碍检测传感器进行指标性能分析,基于毫米波雷达传感器设计了输电线路规避系统,基于毫米波雷达采集到的障碍信息,采用恒虚警算法和多目标检测算法,设计了自主动态规避算法,能够适应杂波边缘和多目标干扰环境,且只需进行一次模糊数遍历,即可实现多目标的检测,采用流体扰动算法实现对巡线航路的实时规划。试验结果表明,输电线路规避系统对输电导线和地线的测试范围在50m左右,误差小于1m,规避效果良好,对保障无人机巡检系统和输电线路运行安全具有重要的意义。 展开更多
关键词 输电线路 无人机 毫米波雷达 导线 规避
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Anping County Shangchen Wiremesh Products CO.,LTD. 预览
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《中国经贸》 2019年第15期144-145,共2页
Anping County Shangchen Wiremesh Products CO.,LTD. is found in 2010, it is a modem enterprise which set research and development,foreign trade into a whole. The head office is located in “Hometon of Wire Mesh in Chin... Anping County Shangchen Wiremesh Products CO.,LTD. is found in 2010, it is a modem enterprise which set research and development,foreign trade into a whole. The head office is located in “Hometon of Wire Mesh in China” Anping County is famous as hometown of wire mesh. Anping County Shangchen Wiremesh Products CO.,LTD. main products and sales: Gabion Mesh, Wire Mesh Fence, Perforated Metal, Welded Wire Mesh, Filter Mesh, Window Screen, Plastic Net, Filter Cartridge, Metal Basket, Barbecue Wire Mesh, Metal Cage, Fiberglass Mesh, Steel Grating, Metal Wire. Our products are widely used in industry, agriculture, cultivation, construction, transport and mining.By now we have already established friendly business relations with more than 80 countries from Southeast Asia, Europe, America, Middle East,Africa, and the sales amount and customers quadruple annually. 展开更多
关键词 Anping COUNTY Shangchen Wiremesh PRODUCTS CO. LTD. GABION MESH Wire MESH Fence
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打捆机捆丝去除氧化皮装置设计
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作者 师学斌 谢印国 《冶金设备》 2019年第A01期44-46,共3页
目前国内钢厂一些打捆机用的捆丝由于存在氧化皮问题,不论是国产打捆机还是进口打捆机在打捆时,氧化皮会由于抽丝、扭结等受力而脱落至送丝槽等部位,故打捆机常常产生跑丝,卡阻等问题。为了解决此问题,设计并制作了一种去除打捆机捆丝... 目前国内钢厂一些打捆机用的捆丝由于存在氧化皮问题,不论是国产打捆机还是进口打捆机在打捆时,氧化皮会由于抽丝、扭结等受力而脱落至送丝槽等部位,故打捆机常常产生跑丝,卡阻等问题。为了解决此问题,设计并制作了一种去除打捆机捆丝氧化皮装置,并通过对不同直径的捆丝以及不同压下量的分组实验,得出压下量以及捆丝直径的变化对捆丝去氧化皮效果的影响。该装置具有结构简单紧凑,占地面积小,价格低廉,易于操作和维护,能适应各种恶劣的工作环境等特点。具有一定的经济价值和现实意义。 展开更多
关键词 去除 氧化皮 打捆机 捆丝
某火电厂锅炉末级再热器T23/TP347H异种钢接头异常组织分析
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作者 周公文 刘俊建 +2 位作者 吴跃 罗畅 王家庆 《热加工工艺》 北大核心 2019年第1期252-254,共3页
某火电厂锅炉末级再热器异种钢接头(T23/TP347H)在割管检验中发现TP347H侧内壁坡口位置存在长约1.1 mm、宽0.5 mm的异常组织区域。对该接头进行了金相组织分析、扫描电镜分析、能谱分析、机械性能试验和当量温度计算。根据试验结果分析... 某火电厂锅炉末级再热器异种钢接头(T23/TP347H)在割管检验中发现TP347H侧内壁坡口位置存在长约1.1 mm、宽0.5 mm的异常组织区域。对该接头进行了金相组织分析、扫描电镜分析、能谱分析、机械性能试验和当量温度计算。根据试验结果分析得出:该异常组织区域应为在打底焊时选用错误焊丝,发现选用错误焊丝后未能将打底焊焊丝金属清除干净,然后选用TP347H正常焊丝在此基础上继续焊接,从而在焊缝根部残留错误焊丝组织。根据试验结果给出相应的改进建议。 展开更多
关键词 末级再热器 异种钢接头 异常组织 焊丝
线材镦粗成形理论研究 预览
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作者 余五新 李文强 《汽车实用技术》 2019年第15期118-120,共3页
计算了对线材进行横向性局部镦粗时设备所需的镦粗力以及夹具对线材的夹紧力和夹持长度等工艺尺寸。通过Deform有限元模拟软件对线材进行镦粗模拟,将模拟得出的镦粗值与理论计算值进行对比,进一步为相关设备和工艺装备的设计提供技术支撑。
关键词 线材 局部镦粗 镦粗力 Deform模拟
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Three principles for preparing Al wire with high strength and high electrical conductivity
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作者 J.P.Hou R.Li +7 位作者 Q.Wang H.Y.Yu Z.J.Zhang Q.Y.Chen H.Ma X.M.Wu X.W.Li Z.F.Zhang 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第5期742-751,共10页
The trade-off relation between the strength and the electrical conductivity has been a Iong-standing dilemma in metallic materials. In the study, three key principles, i.e.elongated grains, sharp texture and nano-scal... The trade-off relation between the strength and the electrical conductivity has been a Iong-standing dilemma in metallic materials. In the study, three key principles, i.e.elongated grains, sharp texture and nano-scale precipitates, were presented for preparing Al wire with high strength and high electrical conductivity based on the specially designed experiments for breaking the mutually exclusive relation between the strength and the electrical conductivity. The results show that the elongated grains could lead to a higher electrical conductivity in Al wire without sacrificing the strength;while, the <111> sharp texture can efficiently strengthen the Al wire without influencing the electrical conductivity. Furthermore, nano-scale precipitates with proper size can simultaneously improve the strength and electrical conductivity of Al alloy wire. Under the guidance of the above three key principles, Al wires with high strength and high conductivity were prepared. 展开更多
关键词 AL WIRE TEXTURE PRECIPITATES Strength Electrical conductivity
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