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This investigation is in two parts, theory and experimental verification. (1) Theoretical Study In this study it is, for obvious reasons, necessary to analyse the concept of formability first. For the purpose of the present investigation it is sufficient to define the four aspects of formability as follows: (a) the formability of the material at a critical section, (b) the formability of the material in general, (c) process efficiency, (d) proportional increase in surface area. A method of quantitative assessment is proposed for each of the four aspects of formability. The theoretical study also includes the distinction between coaxial and non-coaxial strains which occur, respectively, in axisymmetrical and unsymmetrical forming processes and the inadequacy of the circular grid system for the assessment of formability is explained in the light of this distinction. (2) Experimental Study As one of the bases of the experimental work, the determination of the end point of a forming process, which sets the limit to the formability of the work material, is discussed. The effects of three process parameters on draw-in are shown graphically. Then the delay of fracture in sheet metal forming resulting from draw-in is analysed in kinematical terms, namely, through the radial displacements, the radial and the circumferential strains, and the projected thickness of the workpiece. Through the equilibrium equation of the membrane stresses, the effect on the shape of the unsupported region of the workpiece, and hence the position of the critical section is explained. Then, the effect of draw-in on the four aspects of formability is discussed throughout this investigation. The triangular coordinate system is used to present and analyse the triaxial strains involved. This coordinate system has the advantage of showing all the three principal strains in a material simultaneously, as well as representing clearly the many types of strains involved in sheet metal work.

No description available.

No description available.

No description available.

Industrial development has had a major role in creating the situation where bio-diverse materials and services essential for sustaining business are under threat. A key contributory factor to biodiversity decline comes from the cumulative impacts of extended supply chain business operations. In order to contribute to stopping this decline, the industrial world needs to form a better understanding of the way it utilizes the business and biodiversity agenda in its wider operations. This thesis investigates the perceptions and attitudes to biodiversity from government, society and a wide cross-section of industry. The research includes the extent of corporate attention to and use of environmental business tools and guidelines in reporting on biodiversity issues. A case study of three companies from different industrial sectors is undertaken to observe procurement and related environmental management of their supply chains. The use of accredited and non-accredited environmental management systems (EMS) are analysed as frameworks for introducing biodiversity aspects into supply chain management. The outcome is a methodology, which can be used either as a bespoke in-house biodiversity management system or within an accredited ISO 14001 EMS, for incorporating the assessment and management of the potential risks and opportunities involving environmental impacts on biodiversity of supply chain companies.

This thesis describes the procedures developed to control the quality of centred boiled sweet production at the TREBOR factory at Chesterfield. The current Quality Control theory and documentation of existing sweet process lines is examined and used as a basis to assess the problems and possibilities of implementing techniques in this application. Initial statistical analyses of the range of centres produced and common defects are shown. From these analyses came a confirmation that the Quality Control organisation was essentially limited by the low level of process knowledge and technology and the high level of skill required to operate the current process. Based on this analysis of the problem areas the major necessary improvements were then investigated and corrections implemented. These were the design of the rope sizing equipment, and the establishing of control and monitoring functions within the process. A mechanism for rope sizing was then built, a larger and improved centre pipe was designed and installed, and these together with a photodiode camera system to monitor rope size and reject waste has resolved the problems not resolved by the original quality control system. The results have been, a greater understanding of the way in which Quality Control organisations work in practice, and ways in which a high speed continuous and multivariable process can be altered to facilitate more effective control to enhance the product. TREBOR have gained a manufacturing process line which is improved because of a clear increase in the understanding of the old process, and the modifications necessary to include features for the maintenance of better quality during production. Some of the operators' high skill requirement has been replaced with better designed equipment and in-process monitoring.

This study was carried out in order to investigate the effect of cutting parameters on the conventional hobbing process in which the response is analysed and practically tested. The investigation is n six sections: (i) Assessment of cutting torques and power consumed during hobbing. (ii) The study of the variation of gear teeth surface roughness (iii) Investigation of generated vibrations during hobbing (iv) Analysis of the mechanics of uncut-chip (v) The study of tool wear and tool life (vi) A general viewpoint of the economic problem in hobbing. In section (i) tests were conducted in order to assess readily a method of determining cutting torque encountered by hob shaft. Power consumed during hobbing was also measured by changing various cutting parameters. Observations were taken when hobbing spur and helical gears. Unlike others, the effect of cutting speed was shown to have a significant effect both upon cutting torques and power consumed. In section (ii) the nature of gear teeth surface was discussed. Axial feed, hob speed and hob D.P. were seen to have a highly significant influence on surface roughness. In section (iii) investigation was carried out into the effect of cutting parameters upon the machine tool vibration. Stability was shown to depend strongly upon speed, feed and hob D.P. In section (iv) a practical method to calculate volume of metal removed during hobbing is presented and a theoretical analysis of uncut-chip thickness and width is attempted. In section (v) the wear mechanism in hobbing is discussed, "rake face" wear proved to oe a suitable tool-life criterion when cutting materials less than (20 HB) under normal cutting consitions. Cutting speed was seen to have the highest significant influence on tool life, while axial feed was not significant. Section (vi) combines all the previous effects of cutting parameters to give a general viewpoint of the economic problem in hobbing, where power, surface roughness and tangential cutting force were the only constraints restricting the operability region for the given machining conditions.

Manufacturing companies must consider the environmental and social aspects of their business in order to meet the requirements of sustainable manufacturing (SM). In this context, traditional manufacturing management techniques are being challenged because they do not address environmental concerns. Therefore, to meet the commitment to sustainability, a new manufacturing paradigm is needed to improve these techniques in order to assist practitioners and researchers in overcoming this new challenge. This study addresses Lean Six Sigma (LSS) and Life Cycle Assessment (LCA) as important live manufacturing improvement techniques that are currently handled independently, but there could be value in bringing them together. Researching the integration of LSS and LCA is expected to reveal improvement opportunities that would enhance the financial and environmental performance of SM. The main objective of this research has been therefore to design a framework to integrate LSS and LCA so as to yield an outcome better than that obtained if the two methods are applied in isolation. The thesis explores SM through an extensive literature review and then proceeds with data collection using a mixed-methods approach. Analysis of the knowledge and data acquired reveals that communication, environmental strategy and the market are important factors in integrating LSS and LCA. The data is also used to examine the current state of sustainability in a sample of companies by examining the recommendations put forward by other researchers for the transition to SM. The results show that most companies struggle in SM because these recommendations are not adopted. The findings of the study lead to the development of a framework that can be used to support decision making in sustainable manufacturing and to guide environmental improvement projects. The framework illustrates how conducting a LCA study provides the information to formulate an environmental strategy, and how to undertake a LSS project to make improvements. The framework highlights the importance of upgrading standard LSS tools to include environmental measures. Finally, thought experiments are conducted to demonstrate the usefulness of the framework.

The work reported here reflects the fundamental research undertaken by the author into the technologies of Rapid Prototyping, Rapid Manufacturing and Rapid Tooling. This research was undertaken over 4 years, in a period when these technologies were experiencing huge change, through innovation and development, to produce viable and reliable industrial processes. The research presented here deals with the two low cost, high speed Rapid Prototyping manufacturing processes. The first technology produces concept models for verifying design intent in the early stages of the product development cycle — referred to as the Z-Corps 3D Printing, 3DP process. The second technology investigated was the EnvisionTec 3D Digital Light Manufacturing, DLM process. This is machine capable of producing final parts in real engineering materials. In both cases the default manufacturing settings and materials were evaluated for accuracy, finish and material properties and an experimental test methodology was developed. Each process was then optimised utilising Taguchi techniques and applied to industrial projects. Finite Element Analysis (FEA), has been used to predict best build orientation for these non-isotropic materials. This work investigating the Z-Corps 3D printing process has improved the accuracy by 2%, part strength by 25% using new infiltrates and has been applied to both production of polymer injection mould tool inserts and electrode manufacture. The EnvisionTec Digital Light Manufacturing build parameters have been optimised and characterised for accuracy, hardness, part strength, surface finish. The application of FEA analysis using Non-isotropic properties has been shown to improve product performance by 14% and the optimised process has been applied to Rapid Tooling applications. In all twelve case studies are presented here, several of which have been turned into successful commercial products, and for one case over 1 million products have been sold.