The influence of cutting tool geometry upon aspects of chip flow and tool wear:a theoretical, three dimensional examination of the cutting geometry and the shape of the twist drill

This work is undertaken in the attempt to understand the processes at work at the cutting edge of the twist drill. Extensive drill life testing performed by the University has reinforced a survey of previously published information. This work demonstrated that there are two specific aspects of drilling which have not previously been explained comprehensively. The first concerns the interrelating of process data between differing drilling situations, There is no method currently available which allows the cutting geometry of drilling to be defined numerically so that such comparisons, where made, are purely subjective. Section one examines this problem by taking as an example a 4.5mm drill suitable for use with aluminium. This drill is examined using a prototype solid modelling program to explore how the required numerical information may be generated. The second aspect is the analysis of drill stiffness. What aspects of drill stiffness provide the very great difference in performance between short flute length, medium flute length and long flute length drills? These differences exist between drills of identical point geometry and the practical superiority of short drills has been known to shop floor drilling operatives since drilling was first introduced. This problem has been dismissed repeatedly as over complicated but section two provides a first approximation and shows that at least for smaller drills of 4. 5mm the effects are highly significant. Once the cutting action of the twist drill is defined geometrically there is a huge body of machinability data that becomes applicable to the drilling process. Work remains to interpret the very high inclination angles of the drill cutting process in terms of cutting forces and tool wear but aspects of drill design may already be looked at in new ways with the prospect of a more analytical approach rather than the present mix of experience and trial and error. Other problems are specific to the twist drill, such as the behaviour of the chips in the flute. It is now possible to predict the initial direction of chip flow leaving the drill cutting edge. For the future the parameters of further chip behaviour may also be explored within this geometric model.

Adoption of electronic commerce tools in business procurement:enhanced buying center structure and processes

Modern procurement is being shifted from paper-based, people-intensive buying systems toward electronic-based purchase procedures that rely on Internet communications and Web-enhanced buying tools. Develops a typology of e-commerce tools that have come to characterize cutting-edge industrial procurement. E-commerce aspects of purchasing are organized into communication and transaction tools that encompass both internal and external buying activities. Further, a model of the impact of e-commerce on the structure and processes of an organization's buying center is developed. The impact of the changing buying center on procurement outcomes in terms of efficiency and effectiveness is also analyzed. Finally, implications for business-to-business marketers and researchers are discussed.

e-Business technological innovations

Modern distribution is being shifted from paper-based, people-intensive marketing systems toward electronic-based procedures that rely on Internet communications and web-enhanced software tools. This article develops a typology of e-business technological innovations that have come to characterize cutting-edge distribution management. e-Business tools relevant to marketing channels are organized by the channel process flows that yield communication and transaction enhancements to distribution systems. Further, a model of the impact of e-business on channel performance is developed. The mediating role of channel structure on technology's impact on channel outcomes in terms of efficiency and effectiveness is also analyzed. Finally, implications of the e-business revolution for managers and researchers are discussed.

Society

What is the nature of our current societies? Do we see a clash of civilizations, or the end of history? The advent of globalization, or the birth of the network society? Are we witnessing the emergence of a risk society, or the advent of the knowledge society? More fundamentally, is ‘society’ an ideological construct that should be abandoned? Coming into English from the Latin term ‘societas’ via Old French ‘société’, the etymology of ‘society,’ in the sense of a system adopted by a group of co-existing individuals for mutually beneficial purposes, can be traced back at least to the mid-sixteenth century. By the Age of Enlightenment, ‘society’ was increasingly used in intellectual discourse to characterize human relations, often in contrast to notions of ‘the state’. During the nineteenth century, the concept was subject to highly elaborate treatment in various intellectual fields, such as political economy, philosophy, and legal thought; and ‘society’ continues to be a central conceptual tool, not only for sociology, but also for many other social-science disciplines, such as anthropology, economics, political sciences, and law. The notion resonates beyond the social sciences into the humanities; it is a fundamental concept, like nature, the universe, or the economy. Moreover, ‘society’ remains a highly contested concept, as was demonstrated, for example, by the controversy surrounding the former British prime minister Margaret Thatcher’s pithy assertion of the neoliberal economic wisdom that ‘there is no such thing as society’ (Woman’s Own, 31 October 1987); and by the term’s rehabilitation at the turn of the twenty-first century, not least with the ascendancy of the notion of ‘civil society’. This four-volume collection, a new title in the Routledge Critical Concepts in Sociology series, brings together both canonical and the best cutting-edge research to document the intellectual origins and development of what remains a key framework within which contemporary work in the social sciences in general, and sociology in particular, proceeds. Edited by Reiner Grundmann and Nico Stehr, two leading scholars in the field, this Routledge Major Work makes available the most useful, important and representative treatments of the subject matter, and helps to make sense of the great variety of perspectives and approaches in which social scientists and other thinkers have understood, and continue to understand, society. Fully indexed and with a comprehensive introduction newly written by the editors, which places the collected material in its historical and intellectual context, Society is an essential reference work, destined to be valued by scholars and students as a vital research resource.

The influence of tool geometry on the performance of drilling tools

The main objective of the work presented in this thesis is to investigate the two sides of the flute, the face and the heel of a twist drill. The flute face was designed to yield straight diametral lips which could be extended to eliminate the chisel edge, and consequently a single cutting edge will be obtained. Since drill rigidity and space for chip conveyance have to be a compromise a theoretical expression is deduced which enables optimum chip disposal capacity to be described in terms of drill parameters. This expression is used to describe the flute heel side. Another main objective is to study the effect on drill performance of changing the conventional drill flute. Drills were manufactured according to the new flute design. Tests were run in order to compare the performance of a conventional flute drill and non conventional design put forward. The results showed that 50% reduction in thrust force and approximately 18% reduction in torque were attained for the new design. The flank wear was measured at the outer corner and found to be less for the new design drill than for the conventional one in the majority of cases. Hole quality, roundness, size and roughness were also considered as a further aspect of drill performance. Improvement in hole quality is shown to arise under certain cutting conditions. Accordingly it might be possible to use a hole which is produced in one pass of the new drill which previously would have required a drilled and reamed hole. A subsidiary objective is to design the form milling cutter that should be employed for milling the foregoing special flute from drill blank allowing for the interference effect. A mathematical analysis in conjunction with computing technique and computers is used. To control the grinding parameter, a prototype drill grinder was designed and built upon the framework of an existing cincinnati cutter grinder. The design and build of the new grinder is based on a computer aided drill point geometry analysis. In addition to the conical grinding concept, the new grinder is also used to produce spherical point utilizing a computer aided drill point geometry analysis.

The psychology of work and organizations

From the challenges of sustainability to disruptive technology, work environments face unprecedented change and this major new textbook provides a cutting-edge introduction to how psychology and the world of work interact. Leading international academics, Steve Woods and Mike West, combine the latest research with truly global perspectives to leave students with a fully-rounded understanding of work psychology. Developed from wide-ranging lecturer feedback, three key themes of Ethics and Social Responsibility, Globalization and Cross-cultural Issues, and Environment and Sustainability are threaded throughout every chapter, while an attractive full-colour design and engaging pedagogical devices stimulate student interaction on this rapidly growing course. A full set of lecturer resources including Instructors Manual, PowerPoint Slides and Test Bank make this the complete resource for modern work psychology courses.

The role of the English language in the context of national development vision 2025 with specific reference to agriculture in Tanzania

After thirty years of vacillation, the Tanzanian government has made a firm decision to Swahilize its secondary education system. It has also embarked on an ambitious economic and social development programme (Vision 2025) to transform its peasant society into a modern agricultural community. However, there is a faction in Tanzania opposed to Kiswahili as the medium of education. Already many members of the middle and upper class their children to English medium primary schools to avoid the Kiswahili medium public schools and to prepare their children for the English medium secondary system presently in place. Within the education system, particularly at university level, there is a desire to maintain English as the medium of education. English is seen to provide access to the international scientific community, to cutting edge technology and to the global economy. My interest in this conflict of interests stems from several years' experience teaching English to students at Sokoine University of Agriculture. Students specialise in agriculture and are expected to work with the peasant population on graduation. The students experience difficulties studying in English and then find their Kiswahili skills insufficient to explain to farmers the new techniques and technologies that they have studied in English. They are hampered by a complex triglossic situation in which they use their mother tongue with family and friends, Kiswahili, the national language for early education and most public communication within Tanzania, and English for advanced studies. My aim in this thesis was - to study the language policy in Tanzania and see how it is understood and implemented; - to examine the attitudes towards the various languages and their various roles; - to investigate actual language behaviour in Tanzanian higher education. My conclusion is that the dysfunctionality of the present study has to be addressed. Diglossic public life in Tanzania has to be accommodated. The only solution appears to be a compromise, namely a bilingual education system which supports from all cases of society by using Kiswahili, together with an early introduction of English and its promotion as a privileged foreign language, so that Tanzania can continue to develop internally through Kiswahili and at the same time retain access to the globalising world through the medium of English.

Language and identity in englishes

Key features include: • Discussion of language in relation to various aspects of identity, such as those connected with nation and region, as well as in relation to social aspects such as social class and race. • A chapter on undertaking research that will equip students with appropriate research methods for their own projects. • An analysis of language and identity within the context of written as well as spoken texts. Language and Identity in Englishes examines the core issues and debates surrounding the relationship between English, language and identity. Drawing on a range of international examples from the UK, US, China and India, Clark uses both cutting-edge fieldwork and her own original research to give a comprehensive account of the study of language and identity. With its accessible structure, international scope and the inclusion of leading research in the area, this book is ideal for any student taking modules in language and identity or sociolinguistics.

Sustainable development

The United Nations has pithily defined sustainable development as progress that ‘meets the needs of the present without compromising the ability of future generations to meet their own needs’. But sustainable development remains highly contested and is subject to a wide variety of interpretations, applications, and criticisms. Moreover, those seeking fully to understand this critical concept are confronted with a (sometimes dispiritingly) voluminous body of scholarly, polemical, and journalistic writing. Edited by the acclaimed author of Understanding Sustainable Development (Earthscan, 2008), this new title from Routledge’s Critical Concepts in the Environment series answers the need for an authoritative reference work to make sense of the vast literature on sustainable development, and the continuing explosion in research output. Drawing on a wide variety of sources that take full cognizance of the rich background and necessary adaptability of the concept to the imperatives of time, place, and culture, and which emphasize its connected and transdisciplinary nature, the editor has brought together in four volumes the canonical and the best cutting-edge work to produce an indispensable ‘mini library’. The collection covers the history, mediation, application, and likely future orientations of sustainable development, both conceptually and as a continually emerging practice. Sustainable Development is fully indexed and includes comprehensive introductions, newly written by the editor, which place the collected materials in their historical and intellectual context. It is an essential reference collection and is certain to be valued by scholars and students—as well as serious policy-makers and practitioners—as a vital one-stop research and pedagogic resource.

Innovativeness of Indian firms - catalysts and deterrents

Innovation is the driving force that is crucial for firms to sustain their competitive advantage and for economies and industries in general to surge forward. In comparison to developing economies, developed economies have always maintained greater focus on national innovation systems while the firms from these economies have been investing considerable effort on promoting organisational innovation. As firms became increasingly global, consumers across the world, especially from the emerging economies, are getting a taste of more sophisticated products and services. There was also an infusion of knowledge pertaining to cutting-edge technologies, innovation, processes and management systems into this part of the world. However, studies on organisational innovation have largely been confined to firms from developed economies in order to understand the effects of its determinants (Anderson et al., 2004; Choi and Williams, 2014; Li et al., 2013). Given the differences in the socio-cultural milieu between the developed and emerging economies, more nuanced understanding of the factors affecting and the processes associated with innovation in emerging markets is required.

Empirical expression of tool wear when face milling 416 SS

During a machining process, cutting parameters must be taken into account, since depending on them the cutting edge starts to wear out to the point that tool can fail and needs to be change, which increases the cost and time of production. Since wear is a negative phenomenon on the cutting tool, due to the fact that tool life is reduced, it is important to optimize the cutting variables to be used during the machining process, in order to increase tool life. This research is focused on the influence of cutting parameters such as cutting speed, feed per tooth and axial depth of cut on tool wear during a face milling operation. The Taguchi method is applied in this study, since it uses a special design of orthogonal array to study the entire parameters space, with only few numbers of experiments. Also a relationship between tool wear and the cutting parameters is presented. For the studies, a martensitic 416 stainless steel was selected, due to the importance of this material in the machining of valve parts and pump shafts. Copyright © 2009 by ASME.

The cutting performance of sialon ceramic tools

The thesis deals with a research programme in which the cutting performance of a new generation of ceramic cutting tool material is evaluated using the turning process. In part one, the performance of commercial Kyon 2000 sialon ceramic inserts is studied when machining a hardened alloy steel under a wide range of cutting conditions. The aim is to formulate a pattern of machining behaviour in which tool wear is related to a theoretical interpretation of the temperatures and stresses generated by the chip-tool interaction. The work involves a correlation of wear measurement and metallographic examination of the wear area with the measurable cutting data. Four main tool failure modes are recognised: (a) flank and crater wear (b) grooving wear (c) deformation wear and (d) brittle failure Results indicate catastrophic edge breakdown under certain conditions. Accordingly in part two, the edge geometry is modified to give a double rake tool; a negative/positive combination. The results are reported for a range of workpiece materials under orthogonal cutting conditions. Significant improvements in the cutting performance are achieved. The improvements are explained by a study of process parameters; cutting forces, chip thickness ratio, chip contact length, temperature distribution, stress distribution and chip formation. In part three, improvements in tool performance are shown to arise when the edge chamfer on a single rake tool is modified. Under optimum edge chamfer conditions a substantial increase in tool life is obtained compared with the commercial cutting geometry.

Modelling the dynamics of cutting during turning

This thesis presents an approach to cutting dynamics during turning based upon the mechanism of deformation of work material around the tool nose known as "ploughing". Starting from the shearing process in the cutting zone and accounting for "ploughing", new mathematical models relating turning force components to cutting conditions, tool geometry and tool vibration are developed. These models are developed separately for steady state and for oscillatory turning with new and worn tools. Experimental results are used to determine mathematical functions expressing the parameters introduced by the steady state model in the case of a new tool. The form of these functions are of general validity though their coefficients are dependent on work and tool materials. Good agreement is achieved between experimental and predicted forces. The model is extended on one hand to include different work material by introducing a hardness factor. The model provides good predictions when predicted forces are compared to present and published experimental results. On the other hand, the extension of the ploughing model to taming with a worn edge showed the ability of the model in predicting machining forces during steady state turning with the worn flank of the tool. In the development of the dynamic models, the dynamic turning force equations define the cutting process as being a system for which vibration of the tool tip in the feed direction is the input and measured forces are the output The model takes into account the shear plane oscillation and the cutting configuration variation in response to tool motion. Theoretical expressions of the turning forces are obtained for new and worn cutting edges. The dynamic analysis revealed the interaction between the cutting mechanism and the machine tool structure. The effect of the machine tool and tool post is accounted for by using experimental data of the transfer function of the tool post system. Steady state coefficients are corrected to include the changes in the cutting configuration with tool vibration and are used in the dynamic model. A series of oscillatory cutting tests at various conditions and various tool flank wear levels are carried out and experimental results are compared with model—predicted forces. Good agreement between predictions and experiments were achieved over a wide range of cutting conditions. This research bridges the gap between the analysis of vibration and turning forces in turning. It offers an explicit expression of the dynamic turning force generated during machining and highlights the relationships between tool wear, tool vibration and turning force. Spectral analysis of tool acceleration and turning force components led to define an "Inertance Power Ratio" as a flank wear monitoring factor. A formulation of an on—line flank wear monitoring methodology is presented and shows how the results of the present model can be applied to practical in—process tool wear monitoring in • turning operations.