The recent years, the aerospace industry in particular has embraced and actively pursued the development of stronger high performance materials, namely nickel based superalloys and hardwearing steels. This has resulted in a need for a more efficient method of machining, and this need was answered with the advent of High Efficiency Deep Grinding (HEDG). This relatively new process using Cubic Boron Nitride (CBN) electroplated grinding wheels has been investigated through experimental and theoretical means applied to two widely used materials, M50 bearing steel and IN718 nickel based superalloy. It has been shown that this grinding method using a stiff grinding centre such as the Edgetek 5-axis machine is a viable process. Using a number of experimental designs, produced results which were analysed using a variety of methods including visual assessment, sub-surface microscopy and surface analysis using a Scanning Electron Microscope (SEM), residual stress measurement using X-Ray Diffraction (XRD) techniques, Barkhausen Noise Amplitude (BNA) measurements, surface roughness and Vickers micro-hardness appraisal. It has been shown that the fundamentals of the HEDG process have been understood through experimental as well as theoretical means and that through the various thermal models used, grinding temperatures can be predicted to give more control over this dynamic process. The main contributions to knowledge are made up of a number of elements within the grinding environment, the most important being the demonstration of the HEDG effect, explanation of the phenomenon and the ability to model the process. It has also been shown that grinding is a dynamic process and factors such as wheel wear will result in a continuous change in the optimum grinding conditions for a given material and wheel combination. With the significance of these factors recognised, they can be accounted for within an industrial adaptive control scenario with the process engineer confident of a more efficient use of time and materials to produce a higher quality product at lower cost.

Due to the competitive nature of the global economy, organisations are continuously seeking ways of cutting costs and increasing efficiency to gain a competitive advantage. Field service organisations that offer after sales support seek to gain a competitive advantage through downtime minimisation. Downtime is the time between service requests made by a customer or triggered by equipment failure and the completion of the service to rectify the problem by the field service team. Researchers have identified downtime as one of the key performance indicators for field service organisations. The lack of real-time access to information and inaccuracy of information are factors which contribute to the poor management of downtime. Various technology advancements have been adopted to address some of the challenges faced by field service organisations through automation. The emergence of an Internet of Things (IoT), has brought new enhancement possibilities to various industries, for instance, the manufacturing industry. The main research question that this study aims to address is “How can an Internet of Things be used to optimise field service automation?” The main research objective was to develop and evaluate a model for the optimisation of field services using an IoT’s features and technologies. The model aims at addressing challenges associated with the inaccuracy or/and lack of real-time access to information during downtime. The model developed is the theoretical artefact of the research methodology used in this study which is the Design Science Research Methodology (DSRM). The DSRM activities were adopted to fulfil the research objectives of this research. A literature review in the field services domain was conducted to establish the problems faced by field service organisations. Several interviews were held to verify the problems of FSM identified in literature and some potential solutions. During the design and development activity of the DSRM methodology, an IoT model for FSA was designed. The model consists of:The Four Layered Architecture; The Three Phase Data Flow Process; and Definition and descriptions of IoT-based elements and functions. The model was then used to drive the design, development, and evaluation of “proof of concept” prototype, the KapCha prototype. KapCha enables the optimisation of FSA using IoT techniques and features. The implementation of a sub-component of the KapCha system, in fulfilment of the research. The implementation of KapCha was applied to the context of a smart lighting environment in the case study. A two-phase evaluation was conducted to review both the theoretical model and the KapCha prototype. The model and KapCha prototype were evaluated using the Technical and Risk efficacy evaluation strategy from the Framework for Evaluation of Design Science (FEDS). The Technical Risk and Efficacy strategy made use of formative, artificial-summative and summative-naturalistic methods of evaluation. An artificial-summative evaluation was used to evaluate the design of the model. Iterative formative evaluations were conducted during the development of the KapCha. KapCha was then placed in a real-environment conditions and a summative-naturalistic evaluation was conducted. The summative-naturalistic evaluation was used to determine the performance of KapCha under real-world conditions to evaluate the extent it addresses FSA problems identified such as real-time communication and automated fault detection.

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Nos últimos anos, os processos de manufatura têm sido desenvolvidos assumindo-se uma faixa mais ampla de aplicações e capacidades. Devido a isto, a seleção destes processos está se tornando uma tarefa mais complexa. Ela inclui a análise de aspectos monetários e tecnológicos. Atualmente, a maioria das indústrias de manufatura tem que decidir sobre os investimentos na produção dentro de uma vasta gama de possibilidades. Portanto, uma metodologia inovadora é necessária para suprir os elementos necessários para o processo de decisão aplicado a investimentos nos sistemas de manufatura. Este trabalho propõe uma nova metodologia que estabelece passos com o objetivo de se obter as informações essenciais para a comparação entre sistemas de manufatura. Esta metodologia considera aspectos ao longo do tempo de uma forma integrada. O método proposto é aplicado a um estudo de caso onde o processo de retificação é comparado à uma operação de torneamento na produção de eixos de transmissão para a indústria automotiva. A aplicação do método ilustra o poder de sua aplicação no ambiente industrial. / The manufacturing processes have been developed in the last years assuming a wider range of applications and capabilities. Due to that, the selection of theses processes is usually getting a more complex task. It includes the analysis of technological and monetary aspects. Nowadays, most of manufacturing industries have to decide the investments in manufacturing within a wide range of possibilities. Therefore an innovative methodology is required to provide the necessary elements for a decision process applied to investments in manufacturing systems. This work proposes a new methodology that provides steps in order to obtain the main information for the comparison between manufacturing systems. It considers technological and financial aspects along the time in an integrated way. The proposed method is applied to a case study where the grinding process is compared to a turning operation in the production of transmission shafts for automotive industry. The application of the method illustrates the power of its application in industrial environments.

In the light of the requirement for a controllable and reliable extrusion plant for preforming various types of inorganic pigment into spaghetti shape onto a convective band dryer to facilitate drying, a study of the preforming method currently in use by the sponsors has revealed that the screw extruder being used cannot perform this function satisfactorily. The main reason being the thixotropic nature of the pigments. They do not readily tolerate mixing or working, which is inherent in the screw extruder. This necessitated a study of other preforming methods. The thesis reviews the available methods of preforming, existing theories on extrusion of material, and various extruder concepts generated during the initial stages of the project. The concept chosen is discussed. A mathematical model based on test results carried out on a Laboratory model of the chosen extruder concept and tile complete design of the full scale extrusion machine, together with its charging units and the plants' control system is presented. An analysis of the performance tests carried out on the new plant is discussed. The thesis concludes with a comparison between the new plant and the screw extruder in current use regarding their performances and product qualities. Proposals for further work and test are also made.

The butt fusion process is extensively used in the joining of polyethylene (PE) pipes by the water and gas industries. This welding process although deceptively simple, is rather poorly understood, with much of the initial developments being of a rather empirical nature. The Water Research centre (WRc) have funded the present research in an attempt to optimise the welding of high pressure pipeline (PE100) systems. The main aims of this research were to investigate the effect of different welding conditions on the physical and mechanical properties of the joints produced and to investigate these effects on the micro- and macro-structures of the joints produced. A series of welds were made using Eltex Tub 124 and Rigidex 002-50 pipes of 180mm diameter. The fusion pressure and heatsoak times were varied. A milling machine witha twin cutter arrangement was used to obtain the test specimens from around the circumference of the pipes. Differential scanning calorimetry was used to study the effect of sample preparation methodology on the thermo-oxidative stability. Polarised light microscopy and image analysis were used to study the macro- and micro-structural developments in the weld joint. Joint strength was evaluated via standard and non-standard tensile test methods. Milling the samples to produce the test specimens was found to decrease significantly the thermo-oxidative resistance of the polymer. Reasons for this behaviour have been proposed. In order to achieve high quality thin films from microtomy, custom-made blades were used. This programme also developed the optimum polishing method for the microtomed blades. The macro-structure of the bead: its shape and dimensions were found to be a function of temperature and pressure. Correlation was found between the bead geometry and the position around the circumference of the pipe. The macrostructures within the weld zone also showed this dependence on the position along the circumference of the pipe. An examination of the microstructures of each weld had shown the presence of five different zones. The feasibility of using microtomed thin sections in a tensile test was demonstrated. The test method provides a means to study failure initiation and propagation in the tensile test specimen. Initial deformation was found to occur in the centre of the melt-affected zone (MAZ) and the final failure occurs at the junction of the weld bead and the bulk polymer. Tests on films without the weld bead showed that maximum deformation occurred at the centre of the sample within the MAZ. The presence of the bead and the asymmetry in the test specimens caused by the welding process were found to have a significant influence on the failure mode and the failure strain. The strain rate was also found to play a significant role in both beaded and debeaded samples. The failure was initiated from the pseudo notches in the beaded samples. In the debeaded sample the failure was within the MAZ.

The economic aspects of the design of fabricated components have been analysed and clarified. The parameters affecting fabrication economy have been discussed based on the information available to a designer. The approach to the most effective design parameters has been studied and specified.

The present research has arisen from a continuation of the WRAPS (Welding Robotic Adaptive Programming and Simulation) project at Loughborough University, and its development as the supervisory controller of a flexible welding system. A knowledge based expert system (PIKBES) has been developed for on-line expert modification of pre-programmed welding procedures during fabrication of batches in a flexible adaptive robotic welding environment.