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Produced by existing size reduction technologies, rubber crumb is the most valuable type of recycled material. However, only a limited amount of untreated crumb can be used in new tyres due to significant property loss. The de-vulcanisation process offers the potential for providing high quality recycled material that can be used as a substitute for virgin rubber. Rubber materials produced during industrial trials that formed the development stages of the novel DeVulCO”2 de-vulcanisation technology, were used in this work. A practical way to characterise de-vulcanised and re-vulcanised waste tyre materials and blends with virgin compound was established. This work showed that simple to obtain and understand parameters, acquired from tests that are commonly used in the rubber industry, such as Mooney viscosity, Mooney relaxation and curing can be successfully used to indicate the efficiency of the de-vulcanisation process and hence, to assist the research and development stages of the de-vulcanisation process and to assure quality control. Good correlation was evident between these parameters and the network characterisation parameter (Vr) obtained from the swelling measurements that are known to be a reliable guide but are more time consuming to perform. In this work, the Mooney relaxation test was successfully extended to characterise some de-vulcanised compounds (automotive weather strip and clothing tape). In addition, the swollen-state 1H-NMR technique was successfully applied to characterise de-vulcanised and subsequently re-vulcanised “closed-loop” tyre materials. A new tool to measure the efficiency of the de-vulcanisation process has been devised, based on a comparison of the peak areas in the olefinic region of rubber extracts analysed by the liquid 1H-NMR technique. This technique is capable of characterising different components of a rubber blend (e.g. NR, BR) and is suitable for carbon black filled compounds. The results of this work have confirmed the potential of the DeVulCO”2 technology and have indicated that up to 20% of de-vulcanisate can be blended with virgin tyre compound without significant deterioration of the key performance properties.

Electrochemical machining (ECM) is a non-conventional machining technique capable of machining any conductive substrate, regardless of its physical properties e.g. hardness. ECM became an attractive method due to its ability to machine substrates without creating a defective surface layer. ECM utilises electrolysis; a small gap is maintained between two electrodes whilst a favourable potential is applied between them to remove material from the workpiece. The parameters are adjusted to obtain the desired machining results i.e. surface finish, machining resolution and machining rate. Much work has been conducted for the anodic dissolution of stainless steels and brass but little work outside of these materials is available. This work demonstrates the applicability of ECM for a new range of materials; superconductors and semiconductors, along with the application of ECM for medical needle production and an alteration to the machine set up to anodically dissolve titanium metal at reduced potentials. Through a series of electrochemical techniques, namely polarisation curves, machining potentials were defined for a cuprate superconductor and a semiconductor. These were then demonstrated as suitable settings by completing tests on an electrochemical machine. Hypodermic needles were created on an electrochemical machine and polarisation curves of titanium with the addition of ultrasonic vibrations were used to demonstrate the anodic dissolution of titanium at much reduced potentials.

Being typical of manufacturing industry currently, "islands of automation" have severely limited further productivity increases. As being gradually realised, CIM (Computer Integrated Manufacturing) can provide opportunities for higher productivity, and CIM systems integration is the major task for achieving CIM. With reference to the background, this research project was mainly concerned with formalising flexible CIM systems integration architectures and evolving generic and flexible integration tools and methods.

This thesis introduces a conceptual multi-layered reference model to deal with representing information in a visual scene and to relate this data to similar data structures used within manufacturing processes. In this model, information is processed by a set of algorithms organised within layers of hierarchy. The bottom layer deals directly with data collected by the sensors and the top-most layer offers an interface to the different related manufacturing processes. The building elements of the model and the functionality of each layer are examined with respect to different potential implementation. Through a study of typical vision problems, the thesis shows how conventional image processing solution can be re-implemented in a compatible way with the reference model with the advantage of making use of standard algorithms and development tools. The thesis also examines the impact of using machine vision, based on layered model with other manufacturing entities, and the resulting consequences on computer-integrated manufacturing strategy.