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1 – 10 of over 101000
Article
Publication date: 10 July 2017

Milan Djordjević, Vesna Mandić, Srbislav Aleksandrović, Vukić Lazić, Dušan Arsić, Ružica R. Nikolić and Zvonko Gulišija

The purpose of this paper is comparison of experimental values of the drawing forces to numerical values in different contact conditions, taking into account the appearance of…

Abstract

Purpose

The purpose of this paper is comparison of experimental values of the drawing forces to numerical values in different contact conditions, taking into account the appearance of galling which occurs due to of difficult drawing process conditions.

Design/methodology/approach

The following two research approaches are used in this paper – the physical modeling, realized by the laboratory experiment, and the numerical simulation of the ironing drawing process. By analyzing the obtained results, the technique of physical modeling, with help of the laboratory equipment and numerical simulation by application of the finite element method, can be successfully used in studying the thin sheet ironing – strip drawing process.

Findings

It is significant to compare values of the deformation forces obtained by physical experiment to values obtained by the numerical simulation. In that way, it is possible to compare applied contact conditions (four lubricants in that case) and estimate matching of experimentally and numerically obtained results of the deformation forces. Presented results point out very good technological characteristics of ecologically friendly lubricant (single-bath) and grease based on MoS2. Significant decrease of the deformation force was achieved by its application, as well as maintaining of the lubricant’s layer during the forming process and almost complete elimination of galling on the contact.

Practical implications

Numerical analysis of stresses in the working piece wall, during the thin sheet strip drawing, requires precise values of the friction coefficient. It is an important indicator because one can define the contact conditions as the input data for the numerical simulation, based on its values for each type of lubricants and each value of the compressive lateral force.

Originality/value

The environmentally friendly lubricant tested exhibits a more favorable distribution of the drawing force during the process, mainly in experimental case. Grease based on MoS2 has good lubricating properties but that lubricant is conventional and environmentally unacceptable. Ecologically friendly lubricant can be successfully used in real ironing strip drawing process especially for high values of holding force achieving an increased tool life.

Details

Industrial Lubrication and Tribology, vol. 69 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 1 March 1956

The following are extracts from a paper presented to The Institution of Mechanical Engineers (by whose permission they are reproduced) by Professor D. G. Christopherson, O.B.E.…

Abstract

The following are extracts from a paper presented to The Institution of Mechanical Engineers (by whose permission they are reproduced) by Professor D. G. Christopherson, O.B.E., Ph.D., B.A., M.I.Mech.E., (Department of Mechanical Engineering, Leeds University), and H. Naylor, B.Sc., G.I.Mech.E., (Shell Research Ltd.), on April 1st, in London. Their paper also included a section devoted to showing that the experiments here extracted could be confirmed by theoretical considerations.

Details

Industrial Lubrication and Tribology, vol. 8 no. 3
Type: Research Article
ISSN: 0036-8792

Article
Publication date: 1 March 1970

For the drawing of wire there are four types of media which are used as lubricants; water emul‐sions, solids (soaps), non‐aqueous fluids and “pigemented” vehicles. Emulsions and…

Abstract

For the drawing of wire there are four types of media which are used as lubricants; water emul‐sions, solids (soaps), non‐aqueous fluids and “pigemented” vehicles. Emulsions and some soaps, such as the alkali soaps, rely, in part, on the forma‐tion of an interfacial film of metallic soap which gives a film of reasonably high viscosity.

Details

Industrial Lubrication and Tribology, vol. 22 no. 3
Type: Research Article
ISSN: 0036-8792

Article
Publication date: 6 February 2017

Kai Meng

This paper aims to discuss the combination of electrospinning and melt blowing in theory, which may be a good way to produce nanofibers.

Abstract

Purpose

This paper aims to discuss the combination of electrospinning and melt blowing in theory, which may be a good way to produce nanofibers.

Design/methodology/approach

In this paper, the electrostatic field and the air flow field were numerical simulated and analyzed, the compound field of which was also discussed.

Findings

It is pointed out that the air flow angle will be a key factor to produce nanofibers in the compound process of electrospinning and melt blowing.

Originality/value

The combination of electrostatic force and air drawing force may be a good way to produce nanofibers when the material is high viscosity melt. Air jets with high temperature and high velocity will provide favorable conditions for attenuating the polymer jet. The flow angle of the air jets effect the whole attenuation force exerted to the polymer jet and should be selected properly.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 27 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 December 2004

Jaroslav Mackerle

Sheet metal forming is a process of shaping thin sheets of metal by applying pressure through male or female dies or both. In most of used sheet‐formating processes the metal is…

4537

Abstract

Sheet metal forming is a process of shaping thin sheets of metal by applying pressure through male or female dies or both. In most of used sheet‐formating processes the metal is subjected to primarily tensile or compressive stresses or both. During the last three decades considerable advances have been made in the applications of numerical techniques, especially the finite element methods, to analyze physical phenomena in the field of structural, solid and fluid mechanics as well as to simulate various processes in engineering. These methods are useful because one can use them to find out facts or study the processes in a way that no other tool can accomplish. Finite element methods applied to sheet metal forming are the subjects of this paper. The reason for writing this bibliography is to save time for readers looking for information dealing with sheet metal forming, not having an access to large databases or willingness to spend own time with uncertain information retrieval. This paper is organized into two parts. In the first one, each topic is handled and current trends in the application of finite element techniques are briefly mentioned. The second part, an Appendix, lists papers published in the open literature. More than 900 references to papers, conference proceedings and theses/dissertations dealing with subjects that were published in 1995‐2003 are listed.

Details

Engineering Computations, vol. 21 no. 8
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 10 September 2019

Yan Liu, Hai Wang, Wei Zhao, Min Zhang and Hongbo Qin

Inspired by the development of eco-friendly flexible electronics, this paper aims to present a series of paper-based electronics drawn by pencils, which can be used as favorable…

234

Abstract

Purpose

Inspired by the development of eco-friendly flexible electronics, this paper aims to present a series of paper-based electronics drawn by pencils, which can be used as favorable sensing elements in daily life.

Design/methodology/approach

Pencil traces are deposited on the porous surface of Xerox paper by the mechanical exfoliation during writing process, which can be used as basic components to construct functional electronics for daily sensing applications. By changing pencil grade, the obtained traces can work as conductive wires, electrodes, resistors and piezoresistive gauges.

Findings

The experimental results confirm their practical applications in sensing several daily activities, including finger motion, touching and the temperature of water in paper cup. Moreover, the used electronics can be easily handled and recycled.

Research limitations/implications

The shortage in functionality, reliability and performance consistency induced by manual operation is an evident challenge, which makes the pencil-on-paper devices more suitable to work as a temporary solution to satisfying the demands from emergency circumstances.

Originality/value

The pencil-on-paper devices, motivated by the electroconductibility and piezoresistivity of pencil trace, can be explored as sensing prototypes in detecting daily activities. Meantime, their advances in easy accessibility, rapid fabrication, low cost and eco-fitness endow them excellent capacity of meeting the “on-site, real-time” demands.

Details

Circuit World, vol. 45 no. 4
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 1 April 1983

GRADUALLY, industrial leaders are becoming optimistic. Business chiefs on both sides of the Atlantic are saying that, at long last, they can see the light at the end of the tunnel.

Abstract

GRADUALLY, industrial leaders are becoming optimistic. Business chiefs on both sides of the Atlantic are saying that, at long last, they can see the light at the end of the tunnel.

Details

Work Study, vol. 32 no. 4
Type: Research Article
ISSN: 0043-8022

Book part
Publication date: 10 August 2017

James Moir

This chapter considers the political controversy in Britain over the lifting of restrictions of freedom of movement on European Union (EU) citizens from Bulgaria and Romania in…

Abstract

This chapter considers the political controversy in Britain over the lifting of restrictions of freedom of movement on European Union (EU) citizens from Bulgaria and Romania in January 2014. The response of the then Conservative-Liberal Democrat Coalition Government centred on altering the rules on the payment of welfare benefits to potential new EU immigrants such that they would not be entitled to claim these benefits for 3 months after entry to the United Kingdom. This policy led to a split in the coalition, with the Liberal Democrat leadership claiming that it was a panicked move by the majority Conservative coalition partner, and moreover that it was a blatant attempt to appeal the electorate in an effort to be seen to be doing something to stop the welfare benefit system from being abused by ‘foreigners’. The backdrop to this political fracas centred on the economic contribution of East European immigrants to Britain and the claim and counterclaim over the issues jobs, welfare benefits and services such as English language support in schools. These contentious issues are examined in terms of an analysis of online comments to posted in reaction to a political interview with Vince Cable, the Liberal Democrat business secretary, who claimed that the Conservatives were attempting to placate public disquiet over immigration as a response to the rising popularity of the United Kingdom Independence Party.

Details

National Identity and Europe in Times of Crisis
Type: Book
ISBN: 978-1-78714-514-6

Keywords

Article
Publication date: 1 May 1993

S. AITA, E. HAUG, F. EL KHALDI, D. LEFEBVRE and E. DI PASQUALE

A sheet metal forming simulation code has been developed, based on the explicit time integration scheme and Mindlin shell theory. It has been used for the analysis of a number of…

Abstract

A sheet metal forming simulation code has been developed, based on the explicit time integration scheme and Mindlin shell theory. It has been used for the analysis of a number of industrial parts. After recalling some modelling issues, this paper describes an industrial methodology based on the experience of those analyses. The aim of the methodology is to provide, at early design stage, information on the product formability with a workload and lead time adapted to the design delays. Concurrently 2D analyses, critical zones studies and coarse mesh global investigations can be used, with a flexible number of iterations, prior to full refined analyses of the forming process. The application of the methodology on several industrial examples is discussed.

Details

Engineering Computations, vol. 10 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

Open Access
Article
Publication date: 13 September 2022

Oliver Disney, Mattias Roupé, Mikael Johansson and Alessio Domenico Leto

Building information modeling (BIM) is mostly limited to the design phase where two parallel processes exist, i.e. creating 2D-drawings and BIM. Towards the end of the design…

4131

Abstract

Purpose

Building information modeling (BIM) is mostly limited to the design phase where two parallel processes exist, i.e. creating 2D-drawings and BIM. Towards the end of the design process, BIM becomes obsolete as focus shifts to producing static 2D-drawings, which leads to a lack of trust in BIM. In Scandinavia, a concept known as Total BIM has emerged, which is a novel “all-in” approach where BIM is the single source of information throughout the project. This paper's purpose is to investigate the overall concept and holistic approach of a Total BIM project to support implementation and strategy work connected to BIM.

Design/methodology/approach

Qualitative data were collected through eight semi-structured interviews with digitalization leaders from the case study project. Findings were analyzed using a holistic framework to BIM implementation.

Findings

The Total BIM concept was contingent on the strong interdependences between commonly found isolated BIM uses. Four main success factors were identified, production-oriented BIM as the main contractual and legally binding construction document, cloud-based model management, user-friendly on-site mobile BIM software and strong leadership.

Originality/value

A unique case is studied where BIM is used throughout all project phases as a single source of information and communication platform. No 2D paper drawings were used on-site and the Total BIM case study highlights the importance of a new digitalized construction process.

Details

Smart and Sustainable Built Environment, vol. 13 no. 3
Type: Research Article
ISSN: 2046-6099

Keywords

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