Relevant bibliographies by topics / Roll flattening

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Academic literature on the topic 'Roll flattening'

Author: Grafiati
Published: 4 June 2021
Last updated: 11 February 2022

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Journal articles on the topic "Roll flattening"

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Ilmola, Joonas, Aarne Pohjonen, Jari Larkiola, and Jari Nylander. "A New Method Predicting Contact Length and Flattening in Temper Rolling." Key Engineering Materials 716 (October 2016): 605–13. http://dx.doi.org/10.4028/www.scientific.net/kem.716.605.

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The current trend in temper rolling is to make a small reduction to steel strip in order to achieve higher strength with good formability and toughness. In addition, very high strength steels can be cold rolled twice with very small reductions. This causes problems in setup values for cold rolling. Rolling models are usually overestimating roll flattening in the case of small reductions.In temper rolling thickness reduction is small (0.5 – 3%) and the elastic deformation of the work roll should be taken into account [3]. However, standard circular arc roll gap models (e.g. Bland Ford Ellis combined with Hitchcock model) fail to predict the roll flattening and thus the rolling force [4]. In this work, finite element method has been used to define a simplified model for work roll flattening and contact length. Model describes the effect of reduction, strength of steel strip and roll radius.
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Mauer, Paul, Bernhardt Weyh, and Paul Josef Mauk. "Hybrid Calculations of Bending Deformations for 20 Roll Cold Rolling Mill." Key Engineering Materials 716 (October 2016): 856–63. http://dx.doi.org/10.4028/www.scientific.net/kem.716.856.

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In multi-high mills, the slim fixed floating work rolls are supported by primary and secondary intermediate rolls and several supporting rolls mounted pairs-wise on supporting shafts. Over the eccentric adjustment of saddle assemblies and hydraulic adjustment device the roll gap adjusts the specific elastic bending deformation of the support system. Based on a hybrid calculation model the influence and limits of an active adjustment device for 20 roll mill will be presented. Thereby the bending deformations as well as the contact deformations of the complete system including the forming process in settings of the elementary plasticity theory (EPT) will be considered.The modeling of the bending deformations of the roll systems are based on FE-Beam elements. The flattening in the contact zone between the rolls will be formulated by a modified non-linear approach, according to Hertz-Johnson. The contact of the deformed zone is aligned in the discretized EPT-roll model by Alexander with Hitchcock-flattening. The iterative analysis of the compact models leads to “force-deformation-relations”, which provides the influence of the variation of the gap. The force-deformation-relations will be detailed discussed in parameter studies of a real 20 roll mill.
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Li, Ling, Ryo Matsumoto, and Hiroshi Utsunomiya. "Experimental Study of Roll Flattening in Cold Rolling Process." ISIJ International 58, no. 4 (2018): 714–20. http://dx.doi.org/10.2355/isijinternational.isijint-2017-623.

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Yuan, Zheng Wen, Hong Xiao, Hong Biao Xie, and Shao Kun Zhang. "Analysis on the Error of Semi-Infinite Body Model in Roll Flattening Calculation." Advanced Materials Research 712-715 (June 2013): 1213–16. http://dx.doi.org/10.4028/www.scientific.net/amr.712-715.1213.

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To improve the accuracy of roll flattening calculation based on semi-infinite body model, a more accurate roll flattening model is proposed in this paper, which is derived basing on boundary integral equation method. The lateral surface displacement decay functions are established. Based on the boundary integral equation method, the numerical solution of the finite length semi-infinite body under the distributed force is obtained and verified by Finite Element Method (FEM). Based on the new model, the error of semi-infinite body model is analyzed in different length-diameter ratio and non-contact barrel length. Quantitative relationship and the scope of semi-infinite body model are obtained.
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MATSUMOTO, Hiromi, and Toshiyuki SHIRAISHI. "Elastic-Plastic Theory of Temper Rolling with Noncircular Roll Flattening." Journal of the Japan Society for Technology of Plasticity 49, no. 565 (2008): 153–57. http://dx.doi.org/10.9773/sosei.49.153.

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Li, Bo, Qing Dong Zhang, and Xiao Feng Zhang. "Effect of Three Types of Driving Modes of Rolling Mill with Six Rolls on the Friction Force between Rolls." Advanced Materials Research 572 (October 2012): 176–80. http://dx.doi.org/10.4028/www.scientific.net/amr.572.176.

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Three-dimensional finite element model of rolling mill with six rolls in a factory is modeled by nonlinear FEM software called ABAQUS. It is a three-dimensional elastic-plastic rolling model. It includes not only elastic-plastic deformation of strip but also the bending of roll system and flattening of rolls. It can describe the changes in friction force between rolls better. Conclusions are as follows. When the driving roll is the backup roll, friction force between the backup roll and the intermediate roll is easy to reach the maximum value, slipping phenomenon is easy to appear. When the driving roll is the intermediate roll, friction force between the intermediate roll and the work roll is easy to reach the maximum value, slipping phenomenon is easy to appear. When the driving roll is the work roll, the changes in frictional force between the rolls is smooth. Slipping phenomenon is not easy to appear.
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Shinkin, Vladimir N. "Plastic Twisting of Erect Metal Roller." Solid State Phenomena 299 (January 2020): 487–93. http://dx.doi.org/10.4028/www.scientific.net/ssp.299.487.

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The twisting of an erect round metal roller (beam, roll) has a place in many metallurgical processes. For example, in the rolls of a wide-band mill at rolling of metal slab, in the leading rolls of flattening machines, in the asymmetric three-roll machines at bending of metal sheet, and so on. Under the large external torques in an erect metal roll, the plastic deformations can occur, which lead to the large residual stresses after an unloading of round roll. These residual stresses can bend the axis of the roll or cause it to a collapse under the subsequent loads. To estimate the value of residual stresses, it is necessary to know the spring-back factor of roll at a twisting. In this article, we have obtained the spring-back factor of the erect roll under a twisting.
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Bai, Z. H., Y. Xing, S. Y. Liu, B. Y. Li, Y. X. Liu, and Y. Y. Cui. "Calculating the flattening coefficient between roll gaps at the horizontal deflection of work rolls." Ironmaking & Steelmaking 46, no. 2 (2017): 184–92. http://dx.doi.org/10.1080/03019233.2017.1364036.

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Dixon, A. E., and W. Y. D. Yuen. "The development of a fast and robust computer model for metal rolling." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 217, no. 2 (2003): 169–79. http://dx.doi.org/10.1243/095440503321148812.

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A combined analytical/numerical solution method is developed to solve the equations that describe stresses in the plastic deformation of metal strip during rolling together with the resultant roll flattening. This gives a model that is more robust and computationally faster for the same accuracy than standard numerical schemes. Initially, the model assumes the elastically deformed rolls to be approximated by a circular arc profile when in contact with the strip, but it is later extended to calculate the deformed roll profile from the pressure profile through the roll gap. Both versions are suitable for on-line use in predicting the necessary roll force for the rolling of metal strip to a given thickness reduction.
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Xiao, Hong, Zheng-wen Yuan, and Tao Wang. "Roll Flattening Analytical Model in Flat Rolling by Boundary Integral Equation Method." Journal of Iron and Steel Research International 20, no. 10 (2013): 39–45. http://dx.doi.org/10.1016/s1006-706x(13)60174-0.

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Dissertations / Theses on the topic "Roll flattening"

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Stubbs, Richard Edward. "Development of a general three-dimensional model for on-line control of modern rolling processes." Thesis, Imperial College London, 1996. http://hdl.handle.net/10044/1/8305.

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Azizoğlu, Yağız. "Modeling of Cold Pilgering of Tubes." Licentiate thesis, Högskolan Dalarna, Materialteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:du-25902.

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Cold pilgering is a challenging tube forming process in terms of modeling due to the complexity in kinematic of tools, friction condition and material behavior. The process development has mostly been based on simple formulas and costly full-scale tryouts. The aim in this study is to develop validated Finite element models of cold pilgering to increase the understanding of influence of the process parameters on the produced tubes. In the course of this thesis, three-dimensional mechanical and thermo-mechanical Finite element models of cold pilgering were developed. The commercial code MSC.Marc was used in the simulations. General 3D models are needed to be able to capture asymmetric deformation in cold pilgering. It was found that tool deflections together with elastic deformation of roll dies have considerable influence on the rolling force. Furthermore, the strain rate and temperature effects on the response of the material and thereby on the rolling force were evaluated.
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Books on the topic "Roll flattening"

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Chi, Jack Linchuan. Network Societies and Internet Studies: Rethinking Time, Space, and Class. Edited by William H. Dutton. Oxford University Press, 2013. http://dx.doi.org/10.1093/oxfordhb/9780199589074.013.0006.

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This chapter concentrates on a new perspective of ‘network society’. It offers a convincing case for the need for a global perspective on the social role of the Internet that will counter the potential for ethnocentric universal claims. The chapter then concentrates on research results in Internet Studies along with the three basic dimensions of the network society theory: time, space, and class. The Internet brings a flat world free of serious social problems. However, its promise as a decentralising and flattening force does not defy empirical examination. The types of ‘space of places’ are explained. The network labor and the new information and communications technology (ICT)-based working class highlight the class-making process and the rare chance of social change. The network society and its many insights and critiques about the contemporary world have remained important since the publication of Manuel Castells' triology in 1996–98.
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Carlen, Joe. A Brief History of Entrepreneurship. Columbia University Press, 2017. http://dx.doi.org/10.7312/columbia/9780231173049.001.0001.

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A Brief History of Entrepreneurship charts how the pursuit of profit by private individuals has been a prime mover in revolutionizing civilization. Entrepreneurs often butt up against processes, technologies, social conventions, and even laws. So they circumvent, innovate, and violate to obtain what they want. This creative destruction has brought about overland and overseas trade, colonization, and a host of revolutionary technologies—from caffeinated beverages to the personal computer—that have transformed society. Consulting rich archival sources, including some that have never before been translated, Carlen maps the course of human history through nine episodes when entrepreneurship reshaped our world. Highlighting the most colorful characters of each era, he discusses Mesopotamian merchants’ creation of the urban market economy; Phoenician merchant-sailors intercontinental trade, which came to connect Africa, Asia, and Europe; Chinese tea traders’ invention of paper money; the colonization of the Americas; and the current “flattening” of the world’s economic playing field. Yet the pursuit of profit hasn’t always moved us forward. From slavery to organized crime, Carlen explores how entrepreneurship can sometimes work at the expense of others. He also discusses the new entrepreneurs who, through the nascent space tourism industry, are leading humanity to a multiplanetary future. By exploring all sides of this legacy, Carlen brings much-needed detail to the role of entrepreneurship in revolutionizing civilization.
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Book chapters on the topic "Roll flattening"

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De Blij, Harm. "Globals, Locals, and Mobals." In The Power of Place. Oxford University Press, 2008. http://dx.doi.org/10.1093/oso/9780195367706.003.0005.

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Earth may be a planet of shrinking functional distances, but it remains a world of staggering situational differences. From the uneven distribution of natural resources to the unequal availability of opportunity, place remains a powerful arbitrator. Many hundreds of millions of farmers in river basins of Asia and Africa live their lives much as their distant ancestors did, still remote from the forces of globalization, children as well as adults still at high personal risk and great material disadvantage. Tens of millions of habitants of isolated mountain valleys from the Andes to the Balkans and from the Caucasus to Kashmir are as bound to their isolated abodes as their forebears were. Of the seven billion current passengers on Cruiseship Earth, the overwhelming majority (the myth of mass migration notwithstanding) will die very near the cabin in which they were born. In their lifetimes, this vast majority will have worn the garb, spoken the language, professed the faith, shared the health conditions, absorbed the education, acquired the attitudes, and inherited the legacy that constitutes the power of place: the accumulated geography whose formative imprint still dominates the planet. The regional impress of poverty continues to trap countless millions who are and will be born into it and who, globalization notwithstanding, cannot escape it. The “wealth gap” between the fortunate and the less fortunate, still largely a matter of chance and destiny, evinces a widening range resulting from the perpetuation of privilege and power in the so-called global “core” and its international tentacles. Those disparities, represented at all levels of scale, will entail increasing risk in a world of rising anger and weapons of growing destructive efficiency. At the same time, the notion that the world, if not “flat,” is flattening under the impress of globalization is gaining traction. As noted in the preface, the idea that diversities of place continue to play a key role in shaping humanity’s variegated mosaic tends to be dismissed by globalizers who see an increasingly homogenized and borderless world. “Flatness” is becoming an assumption, not merely a prospect, as implied by the titles of numerous books and articles of recent vintage (Fung et al., 2008).
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Conference papers on the topic "Roll flattening"

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Schaeffer, P., and B. Braho. "Lightweight Work Roll Flattening Model for Severe Rolling Conditions." In AISTech 2020. AIST, 2020. http://dx.doi.org/10.33313/380/129.

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Braho, B., and R. Schaeffer. "Lightweight Work Roll Flattening Model for Severe Rolling Conditions." In AISTech 2021. AIST, 2021. http://dx.doi.org/10.33313/382/167-21215-121.

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Braho, B., and R. Schaeffer. "Lightweight Work Roll Flattening Model for Severe Rolling Conditions." In AISTech 2021. AIST, 2021. http://dx.doi.org/10.33313/382/067.

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Shen, Guangxian, Yongjiang Zheng, and Ming Li. "Development of Statically Determinate Plate Rolling Mills Based on Micro-Scale Parameters." In ASME 2012 International Manufacturing Science and Engineering Conference collocated with the 40th North American Manufacturing Research Conference and in participation with the International Conference on Tribology Materials and Processing. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/msec2012-7311.

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Contemporary plate rolling mills and pinch pass mills, which are unstable during the rolling process, are all statically indeterminate structures influenced by micro-scale parameters. The micro-scale parameters include bending deformations of the rolls and the side clearances between the chocks and the side surfaces of the housing window. All these are less than 1 mm, and they have an important effect on the skeletal structure of the roll systems of the mill. If the influence of micro-scale parameters is not considered in the design of the rolling mill, the skeletal structure of the roll system is incomplete and lacks kinematic links and pairs. The statically indeterminate nature of traditional rolling mills results in numerous disadvantages, including the frequent burning loss of the end-thrust bearing caused by excessive axial forces, the lateral movement of the strip owing to the deviation of the rolling load acting on the both ends of backup roll, the short service life of the four-row radial roller bearings on the back-up roll, and the quality of product tends to deteriorate due to the unstable operation of the control system, to mention a few. Because of the flattening effect between the rolls, the setting of the offset distance does not achieve the desired purpose and leads to the deviation of rolling load due to the asymmetric cross between the roll axes. To alleviate the above shortcomings, a new type of rolling mill with a statically determinate structure in which the horizontal offset distance between the roll axes is set to zero is thus proposed. In order to keep the rolls parallel and prevent cross between the rolls, a thrust device is designed, which also ensures sufficient free space to allow convenient roll replacement and allow for the thermal expansion of the chocks. In addition, back-up roll systems with component force bases as well as intermediate roll systems are designed in accordance with the theory of statically determinate characteristics with micro-scale parameters.
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Zhang, Feng, Arif S. Malik, and Haoliang Yu. "High-Fidelity Roll Profile Contact Modeling by Simplified Mixed Finite Element Method." In ASME 2018 13th International Manufacturing Science and Engineering Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/msec2018-6509.

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Roll diameter surface deviations can generate significant strip flatness defects in the cold rolling of thin gauge metal sheet. The resolution of roll profile deviations can vary between 0.001 and 0.01 mm. In such a high-fidelity contact problem, lack of availability of the measured data, and high computational cost in using the data in simulations, make it very difficult to predict the effects of such deviations. Nonetheless, an understanding of how high-fidelity roll profile deviations can lead to rolled sheet flatness defects is very important since such defects may be unrecoverable. This paper evaluates the ability of a simplified mixed finite element roll-stack model to predict contact behavior effects on the rolled sheet created by high-fidelity roll profile deviations. The simplified finite element method combines 3D Timoshenko beam elements with Winkler elastic foundations. The beam elements are used to capture bending and shear deformation, while the Winkler foundations are tested for their ability to accurately and efficiently capture the high-fidelity flattening-type contact behavior. Results for a simple roll and plate contact case study indicate favorable comparison with the results obtained from a large-scale commercial finite element simulation, and yet the methods requires a small fraction of the associated computing time and memory. The work also offers significant insights into the sheet flatness defects that can arise in cold rolling because of low magnitude but high fidelity roll diameter machining errors.
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Zhao, Huyue, and F. Ehmann Kornel. "Single- and Multi-Stand Chatter Models in Tandem Rolling Mills." In ASME 2008 International Manufacturing Science and Engineering Conference collocated with the 3rd JSME/ASME International Conference on Materials and Processing. ASMEDC, 2008. http://dx.doi.org/10.1115/msec_icmp2008-72530.

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Many different modes of chatter and their possible causes have been identified after years of research, yet no clear and definite theory of their mechanics has been established. One of the most important reasons for this can be attributed to the fact that only oversimplified models with a single input and a single output were historically used to formulate chatter in rolling. Such a situation has hindered a complete analysis of the underlying mechanisms. In this paper, a state-space representation of single- and multi-stand chatter models will be proposed in a rigorous and comprehensive mathematical form for stability analysis of the various chatter mechanisms. First, a dynamic model of the rolling process that utilizes homogeneous deformation theory will be established that includes the material strain-hardening and work roll flattening effects. By coupling this dynamic rolling process model with a structural model for mill stands, a single-stand chatter model in a state-space representation will be proposed. Based on the single-stand chatter model, a multi-stand chatter model will be formulated by incorporating the inter-stand tension variations and the time delay effect of the strip transportation. A simulation program will also be presented for the study of the dynamic rolling process in the time domain and for verifying the results from stability analysis.
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Cooreman, Steven, Dennis Van Hoecke, Martin Liebeherr, Philippe Thibaux, and Mary Yamaguti Enderlin. "Experimental and Numerical Study on the Evolution of Mechanical Properties During Spiral Pipe Forming." In 2016 11th International Pipeline Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/ipc2016-64183.

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Large diameter spiral welded pipes are produced from hot rolled coil. The forming of a spiral pipe out of a coil is a sequence of cold deformation steps which are: decoiling, levelling and 3-roll forming (followed by seam welding). Obviously the material experiences a quite complex deformation history since several strain reversals occur during the different steps. A further complexity is that the strain history will even vary along the thickness as it mainly concerns bending deformation. It is therefore not at all surprising that the mechanical properties on pipe and coil are different. The steel manufacturer is able to control the production of the steel within well-defined process limits. Consequently he can guarantee the properties of his product, i.e. the coil. However, the spiral pipe manufacturer only has limited possibilities to control the steel properties but eventually he is responsible for the properties of his product, i.e. the pipe. A detailed understanding of how spiral pipe forming affects the mechanical properties would definitely help steel mills to specify and target coil strength to ensure the final pipe strength. Therefore an experimental study was launched in which a 4-point bending setup was used to reproduce the different forming steps on lab scale. The mechanical properties were measured at intermediate process steps, i.e. on coil, after levelling, after pipe forming and after subsequent flattening. The last step was included because, in practice, the mechanical properties along the pipe transverse direction are typically measured using flattened tensile samples, i.e. after introduction of an additional cold deformation step with strain reversal. The advantages of this experimental approach are twofold: first, one has full control and knowledge on the deformations introduced during the different steps. Second, the typical statistical variation of mechanical properties from coil to coil or even within one coil is far less pronounced as all samples are taken within a relatively short distance from each other. For a more detailed understanding of the experimental study, an efficient Finite Element model to simulate spiral pipe forming was developed in Abaqus. A nonlinear kinematic-isotropic hardening law was applied to describe the material behavior. In this way it was possible to capture both yield point elongation and the well-known Bauschinger phenomenon. This paper summarizes numerical and experimental results for a 16mm thick X70 grade, where different production parameters (leveller settings, ratio of wall thickness to outer diameter) were considered.
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Fukumoto, M., E. Nishioka, and T. Matsubara. "Effect of Interface Wetting on Flattening of Freely Fallen Metal Droplet Onto Flat Substrate Surface." In ITSC 2000, edited by Christopher C. Berndt. ASM International, 2000. http://dx.doi.org/10.31399/asm.cp.itsc2000p0797.

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Abstract A free falling experiment was conducted as a simulation of a thermal spray process. A flattening behavior of the freely fallen metal droplet impinged onto a flat substrate surface was fundamentally investigated. The substrates were kept at various designated temperatures, and the substrates coated with gold by PVD were also prepared in order to investigate the effect of a wetting at the splat/substrate interface on the flattening behavior of the droplet. A falling atmosphere was atmospheric pressure nitrogen to prevent the oxidation of the melted droplet, and the experiments under low-pressure condition were also conducted. A transition of the splat morphology was recognized in atmospheric pressure nitrogen experiments, that is, the splat morphology on a room temperature substrate was a splash type, whereas that on a high temperature substrate was a disk type. The cross-section microstructure of the splat obtained on the room temperature substrate was an isotropic coarse grain, whereas that on the high temperature substrate was a fine columnar. The grain size changed transitionally with increasing the substrate temperature. Transition temperature on the gold-coated substrate was higher than that on the substrate without coating. The cross-section microstructure of the splat obtained under low-pressure was a fine columnar even on the room temperature substrate. The results indicate that the metal droplet wets better under low-pressure condition than in atmospheric pressure nitrogen condition, and the wetting has a significant role in the flattening of the droplet.
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Escure, C., M. Vardelle, P. Fauchais, and A. Grimaud. "Visualization of Particle Impact in Thermal Spray." In ITSC 2000, edited by Christopher C. Berndt. ASM International, 2000. http://dx.doi.org/10.31399/asm.cp.itsc2000p0743.

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Abstract Many studies have been devoted to particle flattening and resulting splat cooling. However, if recent models allow to compute the particle flattening time evolution, very few experiments in spraying conditions have been achieved to back such calculations. The aim of this paper is to describe an imaging device allowing the visualization of particle impacts on cold and hot surfaces. This technique makes it possible : • to investigate the "impact mode" : splashing, deposition or rebound, • to link the particle parameters at impact and the substrate parameters to the observed impact mode, • and therefore, to have a better understanding of coating formation. It consists in a controlled atmosphere chamber where is followed the impact of a single particle on a substrate which can be inclined. The particle parameters prior to its impact are measured : its surface temperature by fast (100 ns) two-color pyrometry, its velocity and diameter by Phase Doppler Anenometry (PDA). The particle image during flattening, splashing or rebounding is given by a fast camera (exposure/delay time 100ns to 1ms) with possible multi exposures. The camera is triggered by the PDA and/or the pyrometer. It is then possible to calculate for each molten particle its Sommerfeld parameter characterizing its impact mode (rebounding, deposition or splashing) when no solidification occurs during flattening. The substrate are made of stainless steel 304L rapidly covered by alumina splats resulting in a Ra~5-6µm. They are kept at 300°C, temperature at which splats are disk shaped on smooth substrate (Ra<0.05µm). The very preliminary results obtained show that unmolten or partially molten particles rebound in all directions but not elastically : the rebounding particle velocity is 3 to 5 times lower than that of the impacting one. For fully molten particles, splashing occurs in all cases even for low Sommerfeld numbers. It thus seems that the substrate roughness plays a key role in splashing.
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Pascual-Gutie´rrez, Jose´ A., Jayathi Y. Murthy, and Raymond Viskanta. "Confinement Effects in Two-Dimensional Silicon Structures." In ASME 2005 Summer Heat Transfer Conference collocated with the ASME 2005 Pacific Rim Technical Conference and Exhibition on Integration and Packaging of MEMS, NEMS, and Electronic Systems. ASMEDC, 2005. http://dx.doi.org/10.1115/ht2005-72220.

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Two-dimensional silicon structures are currently attracting a great deal of attention due to their potential application in the electronic and energy sectors. Most published works have employed simple face-centered cubic (fcc) models in determining dispersion curves and density of states for silicon. In this paper we address confinement effects in silicon using a two- and three-body environment-dependent interatomic potential (EDIP). Dispersion curves for silicon thin films under free-standing boundary conditions are theoretically computed by means of the dynamical equation. We show how size confinement causes the emergence of new energy levels and a flattening of the dispersion curves, explaining the reduction of phonon group velocities with respect to bulk, and the change in the volumetric specific heat. Our results indicate when confinement effects begin to play a primary role in the dynamical behavior of the structure and allow the prediction of the number of atomic layers above which a silicon film can be considered thick in terms of its dynamical behavior.
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