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The present work has arisen from a continuing need to improve the performance of round-steel lifting (hoist) and mining chains, and the hypothesis that this might be done by modification of the link geometry. The finite element (FE) method has been used to analyse the stresses in the chain links. The effects of link length and the bend radius in the crown were considered. The effect of maintaining link length constant and departing from the conventional straight sided (standard) geometry by changing the link shape from eight shape (pinched), through straight sided, to elliptical has been examined. Mining chains made from non-circular section rod have also been investigated. The finite element work has been supported by practical investigations using through-yield strain gauges.

The results of an extensive series of trials on a 100 tonnes per day cement kiln have provided a fundamental insight into the aerodynamics, burning mechanism and heat transfer in the sintering zone of such kilns. Accurate monitoring of the input and output variables has enabled mass and heat balances to be made on the system, and from these results it has been possible to isolate the areas where major fuel savings can be achieved. Slurry moisture, excess air and external heat losses are all variables where improvements and better control would reduce fuel consumption and increase the efficiency of rotary kilns. It has been shown that the external temperature profile of the kiln shell provides a useful indication of the various reaction regions that exist in the process cycle. From calculations of the heat lost from the shell, it has been shown that half the external heat losses occur from the sintering zone of the kiln. Specialized instrumentation has been developed to measure gas temperatures and extract combustion gas samples during the normal range of operation of the kiln. An analysis of these results has led to a formula to predict the length of the flame as influenced by the significant operating parameters. The measured gas concentrations have been used to predict the combustion rate within the flame, and a favourable comparison of this rate has been made with published data. The measurement of flame temperatures in the kiln has shown that the average flame temperature that may be encountered in a cement kiln is approximately 1800°C. Point temperatures of up to 2100°C were measured, and it was observed that increased excess air produced a shorter, hotter flame, but reduced the temperature of the combusted gases, resulting in a poorer quality product. A mathematical model has been developed to predict the gas and refractory temperature and heat flux profiles occurring in a rotary kiln sintering zone. The method is based on that of Hottel and Sarofim, but modified to account for the specialised firing conditions necessary for cement production. The model has been tested against the measured data obtained from the kiln trials, and the degree of agreement found to be encouraging. Use of this model should enable the cement, lime, and refractory industries to comprehend the effect of changes to operational variables, with a resulting improvement in heat utilisation, product quality and plant life.

This thesis relates to the application of Artificial Intelligence to tool wear monitoring. The main objective is to develop an intelligent condition monitoring system able to detect when a cutting tool is worn out. To accomplish this objective it is proposed to use a combined Expert System and Neural Network able to process data coming from external sensors and combine this with information from the knowledge base and thereafter estimate the wear state of the tool. The novelty of this work is mainly associatedw ith the configurationo f the proposeds ystem. With the combination of sensor-baseidn formation and inferencer ules, the result is an on-line system that can learn from experience and can update the knowledge base pertaining to information associated with different cutting conditions. Two neural networks resolve the problem of interpreting the complex sensor inputs while the Expert System, keeping track of previous successe, stimatesw hich of the two neuraln etworks is more reliable. Also, mis-classificationsa re filtered out through the use of a rough but approximate estimator, the Taylor's tool life equation. In this study an on-line tool wear monitoring system for turning processesh as been developed which can reliably estimate the tool wear under common workshop conditions. The system's modular structurem akesi t easyt o updatea s requiredb y different machinesa nd/or processesT. he use of Taylor's tool life equation, although weak as a tool life estimator, proved to be crucial in achieving higher performance levels. The application of the Self Organizing Map to tool wear monitoring is, in itself, new and proved to be slightly more reliable then the Adaptive Resonance Theory neural network.

Over the past twenty years academics, industry commentators and practitioners in the field of physical distribution have been pre-occupied with the computational and technical side of computerised vehicle routing and scheduling (CVRS). Comparatively little research activity has been carried out on the user or management aspects of the technology. The current study aims to make up for this research deficit by investigating the adoption of CVRS technology in the British road freight industry. Moreover, the study evaluates the success of the software used in a strategic, tactical and operational role. The subject of the empirical analyses is the British brewing industry. The findings highlight the fact that CVRS technology is used by only a relatively small number of organisations despite being an effective means to improve the efficiency of transport operations and to provide substantial intangible benefits. The research also develops and empirically validates a model of CVRS in the organisational context. "Organisational context" means that the focus is on the organisational aspects rather than on the technical aspects of the technology. The model investigates relationships between variables and addresses two major research questions: What are the reasons leading to the apparent lack of CVRS system penetration - the "CVRS user-gap"? What are the key factors of successful implementations and subsequent use of the software? To overcome the "CVRS user-gap", the study suggests appropriate measures focusing on individuals' awareness of and attitudes towards the software rather than on improving the quality of the software. To ensure CVRS success, the potential users of CVRS should have a certain level of technological and organisational maturity. Emphasis needs to be placed on adequate system implementation. Special attention should also be given to three critical success factors: the quality of the software; the system operator's ability to use the software; and the drivers willingness and ability to adhere to the computer-generated route proposals.

This work concentrates on the newly growing science of managing tooling in conventional manufacturing. Various Tool Management (TM) problems and the approaches suggested by other researchers to solve these problems are given. This work establishes the basic structure of TM applicable to a conventional manufacturing. Systems Analysis and Design Methodology (SSADM) is used to study the information needs of a typical TM System. It is stressed that the majority of TM problems are due to unavailability of correct information. Success of any TM system depends upon having a good Information System. This work focuses on the tool planning problems in batch manufacturing. The causes of tool planning problems are discussed. The research aims to develop a generic methodology for planning the tools. The information required to carry out the primary functions of any Tool Planning System (TPS) is identified. The fundamental characteristics of different tools from the planning perspective are studied in detail. The principles on which a generic TPS could be designed are laid out. The mechanism of a Tool Planning System is developed. The TPS model is implemented using Foxpro, a DBMS. This model illustrates the concepts of planning tools with the information that can be obtained from other functions of manufacturing. The effectiveness of the developed TPS model is investigated using simulation. The impact of the TPS on the performance of a typical Job Shop Environment is studied and compared with other models with traditional stock control approaches. A suitable statistical method is used for analysing and comparing the simulation results. The advantages and the limitations of the TPS are discussed. Some of the potential benefits include, very low tool shortages, minimum number of purchase requirements and better estimation of tool inventory levels. Furthermore, the TPS acts as a firm guideline for planning the tools in time buckets.

Manufacturing industries rely on automated manufacturing systems to improve the efficiency, quality and flexibility of production. Such systems typically consist of a variety of manufacturing machinery and control hardware, e.g. CNC machine tools, robots, PCs, Programmable Logic Controllers (PLCs) etc., which operate concurrently. The cost of developing and implementing an automated manufacturing system is high, and is particularly so if the control system is found to be unreliable or unsafe during operation. Distributed Control Systems are generally used to control complex concurrent systems,At present the methods used to develop DCSs tend to follow a sequence of steps, viz. a statement of the requirements of the DCS, a functional specification of the DCS, the design of the DCS, generation of the software code for the DCS, implementation of the software. This step approach is inadequate because of the dissimilarity of techniques used to represent each step, which leads to difficulties in ensuring equivalence between the final implementation of the DCS and the initial requirements, which in turn leads to errors in the final software. To overcome this, work has been conducted to unify the specification, design, and software coding phases of the DCS development procedure by ensuring formal equivalencies between them. One particular outcome of such previous work is a tool named Petri Net - Occam Methodology, developed by Dr. P. Gray, which produces dependable Occam code for DCSs. Gray's methodology produces readable designs, directly from the specification of systems, in a graphical but formal way, and results in a Petri Net graph which is equivalent to the final Occam code. However, his methodology is not for a complete DCS but only for one containing Transputers. The PLC is widely used in industry and an integral part of DCSs for Automated Manufacture. This research has developed a methodology, named PNPLC, which produces dependable PLC control programs, in a graphical but formal way, directly from a system's specification. It uses the same tool, Petri Nets, for both designing and simulating the control system, and specifies rules which ensure the correct design, simulation and encoding of PLC programs. The PN designs are a one-to-one equivalent to PLC code and can be directly translated into Ladder Diagrams. Therefore if the simulation shows the design to be correct, the final software will be correct. PNPLC works as a stand alone tool for developing dependable PLC control programs, and also unifies with Gray's methodology to produce a complete tool for developing a resilient DCS containing Transputers and PLCs. The unification of the two methodologies is also reported in this thesis. The research work presented in this thesis contributes to knowledge in the field of DCS development. Recommendations for further work regarding the applicability of the unified methodology on a wide scale industrial basis are also given.

Global competition in industry demands that organisations take steps to improve or even redesign their manufacturing systems in order to remain competitive. Such improvements invariably require considerable investment and risk. The use of computer simulation allows managers to understand the underlying dynamics of complex manufacturing systems in order to identify problem areas. The models can also be used to evaluate re-design strategies and options for improvement, thereby reducing the potential risk and increasing the likelihood of a positive return on investment However, developing a valid simulation model that represents the system to a sufficient scope and level of detail to allow confident decision making is a difficult task. The research explores the application of a novel methodology consisting of a questionnaire survey, case studies with expert model builders and action research with a steel manufacturing company. Using these research techniques, this study focuses on the crucial early phases of the simulation model development process. The research demonstrates that the combination and application of the research techniques has proved to be a powerful methodology to explore the dynamic interactions of the early stages of the simulation life cycle. The findings conclude that the simulation life cycle is highly iterative process where it is difficult to identify clear steps between the different stages of a simulation project. The model builders engage in a number of cyclic activities where there is significant interaction with the client stakeholders to ensure that the model is a valid representation of the problem. The increased use of Visual Interactive Simulation Software (VISS) has had a major impact on the life cycle by allowing dynamic models to be created at a very early stage which facilitates the interaction between model builder and client.