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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

摘要:

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    

Static and dynamic analysis of functionally graded fluid-infiltrated porous skew and elliptical nanoplates

《结构与土木工程前沿(英文)》 2023年 第17卷 第3期   页码 477-502 doi: 10.1007/s11709-023-0918-5

摘要: The analysis of static bending and free and forced vibration responses of functionally graded fluid-infiltrated porous (FGFP) skew and elliptical nanoplates placed on Pasternak’s two-parameter elastic foundation is performed for the first time using isogeometric analysis (IGA) based on the non-uniform rational B-splines (NURBSs) basis function. Three types of porosity distributions affect the mechanical characteristics of materials: symmetric distribution, upper asymmetric distribution, and lower asymmetric distribution. The stress–strain relationship for Biot porous materials was determined using the elastic theory. The general equations of motion of the nanoplates were established using the four-unknown shear deformation plate theory in conjunction with the nonlocal elastic theory and Hamilton’s principle. A computer program that uses IGA to determine the static bending and free and forced vibration of a nanoplate was developed on MATLAB software platform. The accuracy of the computational program was validated via numerical comparison with confidence assertions. This set of programs presents the influence of the following parameters on the static bending and free and forced vibrations of nanoplates: porosity distribution law, porosity coefficient and geometrical parameters, elastic foundation, deviation angle, nonlocal coefficient, different boundary conditions, and Skempton coefficients. The numerical findings demonstrated the uniqueness of the FGFP plate’s behavior when the porosities are saturated with liquid compared with the case without liquid. The findings of this study have significant implications for engineers involved in the design and fabrication of the aforementioned type of structures. Furthermore, this can form the basis for future research on the mechanical responses of the structures.

关键词: static bending     free and forced vibrations     nonlocal theory     isogeometric analysis     fluid-infiltrated porous nanoplates    

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

摘要: With recent relevant publications on stochastic motion robots in , , and other journals, research on such robots has gained increasing attention. However, theoretical and applied research on stochastic motion in the field of robotics and mechanisms face many challenges due to the uncertainty of stochastic motion. Currently, a large gap remains in the research of stochastic motion mechanism. In this study, a novel mechanism that can conduct probabilistic rolling is proposed to reach a designated position and achieve overlying movement over a particular area. The mechanism consists of a regular tetrahedron frame, a central node, and four connecting linear actuators. According to mobility and kinematic analyses, the mechanism can implement probabilistic rolling. Each rolling gait has three probable rolling directions, and the mechanism rolls in one of the three directions in probability. A kinematic simulation is conducted, and a control method is proposed on the basis of the moving path analysis. Furthermore, the mathematical principle of probabilistic rolling is revealed in terms of probability theory and statistics. Lastly, a prototype is fabricated. To achieve the rolling function, the design of the linear actuators is improved, and the extension ratio is increased from 0.58 to 1.13. Then, tests are conducted. In a 4 m test site, the mechanism makes 11 moves to reach the target position and covers 29.25% of the site.

关键词: mobile mechanism     probabilistic motion     rolling mechanism     stochastic motion    

Design and stability analysis of continuous skew tied-arch bridge over Bin Jiang River

YU Jiancheng, TONG Hao, HUANG Wei

《结构与土木工程前沿(英文)》 2008年 第2卷 第1期   页码 37-42 doi: 10.1007/s11709-008-0004-z

摘要: A tied arch bridge without wind bracing was built over the Bin Jiang River, with oblique angle of 20°. Its main design details are described and mechanical performances are analyzed. The stability analytical types are also introduced and the first elastic stability theory is used. A space finite element model has been built to analyze the stability performances in both construction and operation stages for single span or continuous, orthogonal or oblique bridge. The influence of stiffness of the end crossbeam is also analyzed. The result shows that out-plane buckling occur for a rigid tie and similar no matter whether it is single span or continuous and orthogonal or oblique. When there are more and stronger inner crossbeams, the influence of the end crossbeams on arch stability becomes unremarkable.

关键词: out-plane buckling     unremarkable     crossbeam     stability analytical     orthogonal    

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

摘要:

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.

关键词: parallel mechanism     rolling mechanism     screw theory    

板带轧制工艺控制理论概要

张进之

《中国工程科学》 2001年 第3卷 第4期   页码 46-55

摘要:

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。

关键词: 连轧过程控制     连轧张力     厚度控制     板形刚度     轧机弹跳方程     综合等储备负荷分配    

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

摘要:

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    

simulation and analysis of periodically oscillating pressure characteristics of inviscid flow in a rolling

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

摘要: Floating liquefied natural gas (LNG) plants are gaining increasing attention in offshore energy exploitation. The effects of the periodically oscillatory motion on the fluid flow in all processes on the offshore plant are very complicated and require detailed thermodynamic and hydrodynamic analyses. In this paper, numerical simulations are conducted by computational fluid dynamics (CFD) code combined with user defined function (UDF) in order to understand the periodically oscillating pressure characteristics of inviscid flow in the rolling pipe. The computational model of the circular pipe flow is established with the excitated rolling motion, at the excitated frequencies of 1–4 rad/s, and the excitated amplitudes of 3°–15°, respectively. The influences of flow velocities and excitated conditions on pressure characteristics, including mean pressure, frequency and amplitude are systematically investigated. It is found that the pressure fluctuation of the inviscid flow remains almost constant at different flow velocities. The amplitude of the pressure fluctuation increases with the increasing of the excitated amplitude, and decreases with the increasing of the excitated frequency. It is also found that the period of the pressure fluctuation varies with the excitated frequency. Furthermore, theoretical analyses of the flow in the rolling circular pipe are conducted and the results are found in qualitative agreement with the numerical simulations.

关键词: pressure fluctuation     rolling     floating production storage and offloading unit for liquefied natural gas (LNG-FPSO) offshore    

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

摘要: Wind turbine gearbox bearings fail with the service life is much shorter than the designed life. Gearbox bearings are subjected to rolling contact fatigue (RCF) and they are observed to fail due to axial cracking, surface flaking, and the formation of white etching areas (WEAs). The current study reviewed these three typical failure modes. The underlying dominant mechanisms were discussed with emphasis on the formation mechanism of WEAs. Although numerous studies have been carried out, the formation of WEAs remains unclear. The prevailing mechanism of the rubbing of crack faces that generates WEAs was questioned by the authors. WEAs were compared with adiabatic shear bands (ASBs) generated in the high strain rate deformation in terms of microstructural compositions, grain refinement, and formation mechanism. Results indicate that a number of similarities exist between them. However, substantial evidence is required to verify whether or not WEAs and ASBs are the same matters.

关键词: rolling contact fatigue (RCF)     white etching area (WEA)     white etching crack (WEC)     adiabatic shear band (ASB)    

Durability of plasma-sprayed Cr3C2-NiCr coatings under rolling contact conditions

Xiancheng ZHANG, Fuzhen XUAN, Shantung TU, Binshi XU, Yixiong WU

《机械工程前沿(英文)》 2011年 第6卷 第1期   页码 118-135 doi: 10.1007/s11465-011-0127-0

摘要:

The aim of this paper was to address the rolling contact fatigue (RCF) failure mechanisms of plasma-sprayed Cr3C2-NiCr coatings under different tribological conditions of contact stress. Weibull distribution plots of fatigue lives of the coated specimens at different contact stresses were obtained. The failure modes of coatings were identified on the basis of wore surface observations of the failed coatings. Results showed that the RCF failure modes can be classified into four main categories, i.e., surface abrasion, spalling, cohesive delamination, and interfacial delamination. The probabilities of the surface abrasion and spalling type failures were relatively high at low contact stress. When the coatings were subjected to abrasion and spalling type failures, the failure of the coating was depended on the microstrcture of the coating. The stress concentration near the micro-defects in the coating may be the may reason for the formation of spall. The coatings were prone to fail in delamination under higher contact stresses. However, the delamination of coating may be related to distribution of shear stress amplitude within coating. The location of maximum shear stress amplitude can be used as a key parameter to predict the initiation of subsurface cracks within coating in rolling contact.

关键词: rolling contact fatigue     coating     Weibull distribution     failure mode     mechanism    

An adaptive data-driven method for accurate prediction of remaining useful life of rolling bearings

Yanfeng PENG, Junsheng CHENG, Yanfei LIU, Xuejun LI, Zhihua PENG

《机械工程前沿(英文)》 2018年 第13卷 第2期   页码 301-310 doi: 10.1007/s11465-017-0449-7

摘要:

A novel data-driven method based on Gaussian mixture model (GMM) and distance evaluation technique (DET) is proposed to predict the remaining useful life (RUL) of rolling bearings. The data sets are clustered by GMM to divide all data sets into several health states adaptively and reasonably. The number of clusters is determined by the minimum description length principle. Thus, either the health state of the data sets or the number of the states is obtained automatically. Meanwhile, the abnormal data sets can be recognized during the clustering process and removed from the training data sets. After obtaining the health states, appropriate features are selected by DET for increasing the classification and prediction accuracy. In the prediction process, each vibration signal is decomposed into several components by empirical mode decomposition. Some common statistical parameters of the components are calculated first and then the features are clustered using GMM to divide the data sets into several health states and remove the abnormal data sets. Thereafter, appropriate statistical parameters of the generated components are selected using DET. Finally, least squares support vector machine is utilized to predict the RUL of rolling bearings. Experimental results indicate that the proposed method reliably predicts the RUL of rolling bearings.

关键词: Gaussian mixture model     distance evaluation technique     health state     remaining useful life     rolling bearing    

薄板坯连铸连轧铁素体+珠光体类型钢的强化与软化

傅杰,吴华杰,刘阳春

《中国工程科学》 2008年 第10卷 第4期   页码 65-72

摘要:

根据钢的综合强化理论,控制A1附近温度下钢中碳的析出,研究了HSLC钢的强化与软化问题。结果表明:薄板坯连铸连轧HSLC钢,强度还可进一步提高;通过回火缓冷,薄板坯连铸连轧HSLC钢ZJ330的σs从344 MPa降至225 MPa,能满足冷轧基板要求。讨论了有关铁素体轧制、超细晶粒钢以及一种可能的新型建筑材料等问题。

关键词: HSLC钢     强化     软化     冷轧基板     超级钢    

Accumulated damage process of thermal sprayed coating under rolling contact by acoustic emission technique

Jia XU,Zhen-yu ZHOU,Zhong-yu PIAO

《机械工程前沿(英文)》 2016年 第11卷 第3期   页码 227-232 doi: 10.1007/s11465-016-0395-9

摘要:

The accumulated damage process of rolling contact fatigue (RCF) of plasma-sprayed coatings was investigated. The influences of surface roughness, loading condition, and stress cycle frequency on the accumulated damage status of the coatings were discussed. A ball-on-disc machine was employed to conduct RCF experiments. Acoustic emission (AE) technique was introduced to monitor the RCF process of the coatings. AE signal characteristics were investigated to reveal the accumulated damage process. Result showed that the polished coating would resist the asperity contact and remit accumulated damage. The RCF lifetime would then extend. Heavy load would aggravate the accumulated damage status and induce surface fracture. Wear became the main failure mode that reduced the RCF lifetime. Frequent stress cycle would aggravate the accumulated damage status and induce interface fracture. Fatigue then became the main failure mode that also reduced the RCF lifetime.

关键词: accumulated damage     spray coating     rolling contact fatigue     acoustic emission    

Numerical analysis of bearing behaviors of single batter piles under horizontal loads in various directions

《结构与土木工程前沿(英文)》 2023年 第17卷 第2期   页码 224-237 doi: 10.1007/s11709-022-0914-1

摘要: The horizontal bearing behavior of a single batter pile (SBP) is vital to its application in practical engineering; however, the horizontal responses of SBPs change with the directions of horizontal loads, and this phenomenon is rarely investigated. Therefore, the directional differences in the horizontal bearing behaviors of SBPs are investigated in this study. Four model tests are conducted to preliminarily examine the effects of the skew angle of horizontal loads on the horizontal bearing capacities and distributions of the bending moments of the SBPs. Subsequently, the differences in the responses of the SBPs under horizontal loads in various directions at full scale are analyzed comprehensively via finite-element (FE) analysis. The effects of the skew angle on SBP-soil interaction are discussed. Moreover, an empirical design method is proposed based on the FE analysis results to predict the bearing ratios of SBPs in medium-dense and dense sand while considering the effects of the skew angle, batter angle, and pile diameter. The method is confirmed to be effective, as confirmed by the close agreement between the predicting results with the model test (reported in this study) and centrifuge model test results (reported in the literature).

关键词: single batter pile     skew horizontal load     model test     finite-element analysis     empirical design method    

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

Static and dynamic analysis of functionally graded fluid-infiltrated porous skew and elliptical nanoplates

期刊论文

A rolling 6U parallel mechanism

Zhihuai MIAO, Yanan YAO

期刊论文

Novel probabilistic rolling regular tetrahedron mechanism

Yonghan GUAN, Yan’an YAO, Chao LIU, Ruiming LI

期刊论文

Design and stability analysis of continuous skew tied-arch bridge over Bin Jiang River

YU Jiancheng, TONG Hao, HUANG Wei

期刊论文

A rolling 3-UPU parallel mechanism

Zhihuai MIAO, Yan’an YAO, Xianwen KONG

期刊论文

板带轧制工艺控制理论概要

张进之

期刊论文

Rolling-element bearings in China: From ancient times to the 20th century

Lie SUN,Ang LI

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

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

Durability of plasma-sprayed Cr3C2-NiCr coatings under rolling contact conditions

Xiancheng ZHANG, Fuzhen XUAN, Shantung TU, Binshi XU, Yixiong WU

期刊论文

An adaptive data-driven method for accurate prediction of remaining useful life of rolling bearings

Yanfeng PENG, Junsheng CHENG, Yanfei LIU, Xuejun LI, Zhihua PENG

期刊论文

薄板坯连铸连轧铁素体+珠光体类型钢的强化与软化

傅杰,吴华杰,刘阳春

期刊论文

Accumulated damage process of thermal sprayed coating under rolling contact by acoustic emission technique

Jia XU,Zhen-yu ZHOU,Zhong-yu PIAO

期刊论文

Numerical analysis of bearing behaviors of single batter piles under horizontal loads in various directions

期刊论文