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Research and industrialization of near-net rolling technology used in shaft parts
Zhenghuan HU, Baoyu WANG, Zhenhua ZHENG
《机械工程前沿(英文)》 2018年 第13卷 第1期 页码 17-24 doi: 10.1007/s11465-018-0480-3
Shaft part rolling is an efficient and green near-net shaping technology offering many advantages, including high production efficiency, high material utilization rate, high product quality, and excellent production environment. In this paper, the features of shaft part rolling are introduced along with the working principles of two main shaft part rolling technologies, namely, cross wedge rolling (CWR) and skew rolling (SR). In relation to this technology, some R&D achievements gained by the University of Science and Technology Beijing are summarized. Finally, the latest developments in shaft part rolling are presented, including SR steel balls, precise forming of camshaft blank by CWR, SR phosphorous copper balls at room temperature, and CWR hollow axle sleeve. Although the shaft part rolling technology has been widely used in China, it only accounts for about 15% of applicable parts at present. Nevertheless, this technology has broad application prospects.
关键词: cross wedge rolling skew rolling near-net rolling shaft part
Special issue: Near-net shaping technology
Dequn LI, Dongming GUO, Qingxue HUANG, Yanchun LOU
《机械工程前沿(英文)》 2018年 第13卷 第1期 页码 1-2 doi: 10.1007/s11465-018-0497-7
Determining casting defects in near-net shape casting aluminum parts by computed tomography
Jiehua LI, Bernd OBERDORFER, Daniel HABE, Peter SCHUMACHER
《机械工程前沿(英文)》 2018年 第13卷 第1期 页码 48-52 doi: 10.1007/s11465-018-0493-y
Three types of near-net shape casting aluminum parts were investigated by computed tomography to determine casting defects and evaluate quality. The first, second, and third parts were produced by low-pressure die casting (Al-12Si-0.8Cu-0.5Fe-0.9Mg-0.7Ni-0.2Zn alloy), die casting (A356, Al-7Si-0.3Mg), and semi-solid casting (A356, Al-7Si-0.3Mg), respectively. Unlike die casting (second part), low-pressure die casting (first part) significantly reduced the formation of casting defects (i.e., porosity) due to its smooth filling and solidification under pressure. No significant casting defect was observed in the third part, and this absence of defects indicates that semi-solid casting could produce high-quality near-net shape casting aluminum parts. Moreover, casting defects were mostly distributed along the eutectic grain boundaries. This finding reveals that refinement of eutectic grains is necessary to optimize the distribution of casting defects and reduce their size. This investigation demonstrated that computed tomography is an efficient method to determine casting defects in near-net shape casting aluminum parts.
关键词: near-net shape casting aluminum parts casting defects low pressure die casting die casting semi-solid casting computed tomography
A rolling 6U parallel mechanism
Zhihuai MIAO, Yanan YAO
《机械工程前沿(英文)》 2011年 第6卷 第1期 页码 96-98 doi: 10.1007/s11465-011-0214-2
Novel probabilistic rolling regular tetrahedron mechanism
Yonghan GUAN, Yan’an YAO, Chao LIU, Ruiming LI
《机械工程前沿(英文)》 2021年 第16卷 第2期 页码 363-378 doi: 10.1007/s11465-020-0628-9
关键词: mobile mechanism probabilistic motion rolling mechanism stochastic motion
A rolling 3-UPU parallel mechanism
Zhihuai MIAO, Yan’an YAO, Xianwen KONG
《机械工程前沿(英文)》 2013年 第8卷 第4期 页码 340-349 doi: 10.1007/s11465-013-0282-6
A novel rolling mechanism is proposed based on a 3-UPU parallel mechanism in this paper. The rolling mechanism is composed of two platforms connected by three UPU (universal-prismatic-universal) serial-chain type limbs. The degree-of-freedom of the mechanism is analyzed using screw theory. Gait analysis and stability analysis are presented in detail. Four rolling modes of the mechanism are discussed and simulated. The feasibility of the rolling mechanism is verified by means of a physical prototype. Finally, its terrain adaptability is enhanced through planning the rolling gaits.
Study on the Path of “Near-zero Emission” Coal-based Clean Energy Ecosystem Development
Zhang Yu-zhuo
《工程管理前沿(英文)》 2014年 第1卷 第1期 页码 37-41 doi: 10.15302/J-FEM-2014007
关键词: near-zero emission clean energy ecosystem study on the path
张进之
《中国工程科学》 2001年 第3卷 第4期 页码 46-55
以最小阻力定律、体积不变条件和秒流量相等条件为内容的经典轧制理论,经试验、演绎形成了较完整的轧制应用技术科学体系,这种体系所反映的是静态规律。在轧制理论发展中引入控制论、信息论、计算机科学等高新技术,对轧制过程进行控制。在轧制理论发展史上,弹跳方程建立之前是以力学为基础建立的经典轧制理论,之后为以力学和控制论为基础建立的基本轧制工艺控制理论。文章提出工艺控制理论概念,是在基本轧制工艺控制理论的基础上建立的新的理论体系,主要内容包括:在连轧张力理论中反映了张力的负反馈,建立了连轧张力理论体系;在厚控过程中,解决扰动的检测问题;在板形理论中,定义了对偶参数,确立了与 厚控理论相似的板形理论体系。
Rolling-element bearings in China: From ancient times to the 20th century
Lie SUN,Ang LI
《机械工程前沿(英文)》 2016年 第11卷 第1期 页码 33-43 doi: 10.1007/s11465-016-0373-2
The development of rolling-element bearings in China has spanned a long period. Based on several typical and important cases, the present article reconstructs the history of rolling-element bearings in China by dividing it into four stages according to the various characteristics of the bearings. The first stage represents the origin of rolling bearings in China, which remains controversial because of several suspected races and cages that were likely the components of bearings more than a millennium ago. At the second stage, a type of simple roller bearing was used for astronomical instruments not later than the 13th century based on clear philological and physical evidence. A similar bearing was also applied to an abridged armillary in the 17th century. Another type of spherical thrust bearings with rolling elements, which is a key component of a traditional Chinese windmill, could support a rotating shaft that moves rotationally and at an angle. At the third stage, the Chinese began studying and using the so-called European-style bearing since the 17th century. Moreover, over the last 100 years, the modern rolling bearing industry was gradually established in China, particularly because of the technology transfer from the Soviet Union in the 1950s. At the fourth stage, the Chinese government initiated the relatively rapid development of bearing technology. The government launched the “bearing movement” from the 1950s to the 1960s to establish the modern bearing industry and to promote rolling bearings as replacement for traditional sliding bearings. Furthermore, a number of large professional factories and institutions in China have continually introduced advanced technology and equipment. At present, these companies and institutions play a significant role in the international bearing industry.
关键词: bearing movement rolling-element bearing China early rolling bearings technology transfer
Yan GU, Yonglin JU
《能源前沿(英文)》 2012年 第6卷 第1期 页码 21-28 doi: 10.1007/s11708-012-0173-2
关键词: pressure fluctuation rolling floating production storage and offloading unit for liquefied natural gas (LNG-FPSO) offshore
Chemisorption solid materials for hydrogen storage near ambient temperature: a review
Yiheng ZHANG, Shaofei WU, Liwei WANG, Xuefeng ZHANG
《能源前沿(英文)》 2023年 第17卷 第1期 页码 72-101 doi: 10.1007/s11708-022-0835-7
关键词: hydrogen storage capacity chemisorption near-ambient-temperature modification methods alloy hydrides
Factors influencing near infrared spectroscopy analysis of agro-products: a review
Xiao XU, Lijuan XIE, Yibin YING
《农业科学与工程前沿(英文)》 2019年 第6卷 第2期 页码 105-115 doi: 10.15302/J-FASE-2019255
The near infrared (NIR) spectroscopy technique has wide applications in agriculture with the advantages of being nondestructive, sensitive, safe and rapid. However, there are still more than 40 error sources influencing the robustness and accuracy of its calibration and operation. Environmental, sample and instrument factors that influence the analysis are discussed in this review, including temperature, humidity and other factors that introduce uncertainty. Error sources from livestock products, fruit and vegetables, which are the most common objects in the field of NIR analysis, are also emphasized in the second part. In addition, studies utilizing different instruments, spectral pretreatments, variable selection methods, wavelength ranges, detection modes and calibration methods are tabulated to illustrate the complications they introduce and how they influence NIR analysis. It is suggested that large scale of data with abundant varieties can be used to build a more robust calibration model, in order to improve the robustness and accuracy of the NIR analytical model, and overcome problems caused by confining analysis to too many uniform samples.
关键词: agro-product error source influence factor near infrared spectroscopy
Guizhong XIE,Dehai ZHANG,Jianming ZHANG,Fannian MENG,Wenliao DU,Xiaoyu WEN
《机械工程前沿(英文)》 2016年 第11卷 第4期 页码 412-422 doi: 10.1007/s11465-016-0396-8
As a widely used numerical method, boundary element method (BEM) is efficient for computer aided engineering (CAE). However, boundary integrals with near singularity need to be calculated accurately and efficiently to implement BEM for CAE analysis on thin bodies successfully. In this paper, the distance in the denominator of the fundamental solution is first designed as an equivalent form using approximate expansion and the original sinh method can be revised into a new form considering the minimum distance and the approximate expansion. Second, the acquisition of the projection point by Newton-Raphson method is introduced. We acquire the nearest point between the source point and element edge by solving a cubic equation if the location of the projection point is outside the element, where boundary integrals with near singularity appear. Finally, the subtriangles of the local coordinate space are mapped into the integration space and the sinh method is applied in the integration space. The revised sinh method can be directly performed in the integration element. A verification test of our method is proposed. Results demonstrate that our method is effective for regularizing the boundary integrals with near singularity.
关键词: computer aided engineering (CAE) boundary element method (BEM) near singularity sinh method coordinate transformation integration space
Review of the damage mechanism in wind turbine gearbox bearings under rolling contact fatigue
Yun-Shuai SU, Shu-Rong YU, Shu-Xin LI, Yan-Ni HE
《机械工程前沿(英文)》 2019年 第14卷 第4期 页码 434-441 doi: 10.1007/s11465-018-0474-1
关键词: rolling contact fatigue (RCF) white etching area (WEA) white etching crack (WEC) adiabatic shear band (ASB)
Modeling of oil near-infrared spectroscopy based on similarity and transfer learning algorithm
Yifei Wang, Kai Wang, Zhao Zhou, Wenli Du
《化学科学与工程前沿(英文)》 2019年 第13卷 第3期 页码 599-607 doi: 10.1007/s11705-019-1807-2
关键词: near-infrared spectroscopy transfer learning similarity modeling
标题 作者 时间 类型 操作
Research and industrialization of near-net rolling technology used in shaft parts
Zhenghuan HU, Baoyu WANG, Zhenhua ZHENG
期刊论文
Determining casting defects in near-net shape casting aluminum parts by computed tomography
Jiehua LI, Bernd OBERDORFER, Daniel HABE, Peter SCHUMACHER
期刊论文
Novel probabilistic rolling regular tetrahedron mechanism
Yonghan GUAN, Yan’an YAO, Chao LIU, Ruiming LI
期刊论文
Study on the Path of “Near-zero Emission” Coal-based Clean Energy Ecosystem Development
Zhang Yu-zhuo
期刊论文
simulation and analysis of periodically oscillating pressure characteristics of inviscid flow in a rolling
Yan GU, Yonglin JU
期刊论文
Chemisorption solid materials for hydrogen storage near ambient temperature: a review
Yiheng ZHANG, Shaofei WU, Liwei WANG, Xuefeng ZHANG
期刊论文
Factors influencing near infrared spectroscopy analysis of agro-products: a review
Xiao XU, Lijuan XIE, Yibin YING
期刊论文
Implementation of sinh method in integration space for boundary integrals with near singularity in potential
Guizhong XIE,Dehai ZHANG,Jianming ZHANG,Fannian MENG,Wenliao DU,Xiaoyu WEN
期刊论文
Review of the damage mechanism in wind turbine gearbox bearings under rolling contact fatigue
Yun-Shuai SU, Shu-Rong YU, Shu-Xin LI, Yan-Ni HE
期刊论文