Influence of geometric shape on the deformation performance of natural jute/epoxy specimens under axial quasi-static compression

The interest in the using of natural composite has been increased significantly in recent years in many application of life due to their distinctive characteristics these like low density, high-energy dissipation ability, and fatigue resistance. Indeed, a seemingly good alternative candidate to metals.This work displays the deformation performance of two different types of geometrical natural composite shapes when subjected to uniaxial quasi-static loading. The purpose is to study the effect of geometrical on the progressive collapse of composite specimens. Two geometrical composite tubes have been fabricated by combination technique of manual lay-up and vacuum bladder moulding. The two types of the proposed tubes, which are the circular and corrugated shape. The experimental work was performed by using bidirectional jute fabric (with 3 layers and 100mm in length) and epoxy resin. Six patterns (three for each one) were tested and evaluated in the same conditions to provide a proper means of comparison between different geometric shapes. The result exhibited both kinds of samples demonstrated stable and progressive deformation with acceptable repeatability during the test process. It also showed the ability to absorb the higher energy of the corrugated samples configuration than the circular samples. Overall, the corrugated pattern configuration can be considered the optimal for crashworthiness structure application compared to a circular composite sample

Tool flow management in batch manufacturing systems for cylindrical components

The objective of the research is to study the design of and operating strategies for advanced tool flow systems in highly automated turning systems. A prototype workstation has been built to aid this process. The thesis consists of three main parts. In the first part the current flexible manufacturing technology is reviewed with emphasis laid on tool flow and production scheduling problems. The 'State-of-the-Art' turning systems are studied, to highlight the requirement of the computer modelling of tool flow systems. In the second part, the design of a computer model using fast modelling algorithms is reported. The model design has concentrated on the tool flow system performance forecasting and improving. Attention has been given to the full representation of highly automatic features evident in turning systems. A number of contemporary production scheduling rules have been incorporated into the computer model structure, with the objectives of providing a frontend to the tool flow model, and to examine the tool flow problems interactively with the production scheduling rules. The user-interface of the model employs conversational type screens for tool flow network specification and data handling, which enhances its user friendliness greatly. An effective, fast, and easy to handle data base management system for tool, part, machine data entries has been· built up to facilitate the model performance. The third part of the thesis is concerned with the validation and application of the model with industry supplied data to examine system performance, and to evaluate alternative strategies. Conclusions drawn from this research and the recommendations for further work are finally indicated

Methodologies for CIM systems integration in small batch manufacturing

This thesis is concerned with identifying the problems and constraints faced by small batch manufacturing companies during the implementation of Computer Integrated Manufacturing (CIM). The main aim of this work is to recommend generic solutions to these problems with particular regard to those constraints arising because of the need for ClM systems integration involving both new and existing systems and procedures. The work has involved the application of modern computer technologies, including suitable hardware and software tools, in an industrial environment. Since the research has been undertaken with particular emphasis on the industrial implementor's viewpoint, it is supported by the results of a two phased implementation of computer based control systems within the machine shop of a manufacturing company. This involved the specific implementation of a Distributed Numerical Control system on a single machine in a group technology cell of machines followed by the evolution of this system into Cell and Machine Management Systems to provide a comprehensive decision support and information distribution facility for the foremen and uperators within the cell. The work also required the integration of these systems with existing Factory level manufacturing control and CADCAM functions. Alternative approaches have been investigated which may have been applicable under differing conditions and the implications that this specific work has for CIM systems integration in small batch manufacturing companies evaluated with regard not only to the users within an industrial company but also the systems suppliers external to the company. The work has resulted in certain generic contributions to knowledge by complementing ClM systems integration research with regard to problems encountered; cost implications; the use of appropriate methodologies including the role of emerging international standard methods, tools and technologies and also the importance of 'human integration' when implementing CIM systems in a real industrial situation

Design and analysis of the internally cooled smart cutting tools with the applications to adaptive machining

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Adaptive machining with internally cooled smart cutting tools is a smart solution for industrial applications, which have stringent manufacturing requirements such as contamination free machining (CFM), high material removal rate, low tool wear and better surface integrity. The absence of cutting fluid in CFM causes the cutting tool and the workpiece subject to great thermal loads owing to higher friction and adhesion, and as a result may increase the levels of tool wear drastically. The increase in cutting temperature may influence the chip morphology which in return producing metal chips in unfavourable ribbon or snarl forms. CFM is difficult to be realized as contaminants can be in various forms in the machining operation and to avoid them totally requires a very tight controlled condition. However, the ecological, economical and technological demands compel the manufacturing practitioners to implement environmentally clean machining process (ECMP). Machining with innovative cooling techniques such as heat pipe, single-phase microduct, cryogenic or minimum quantity lubrication (MQL) has been intensely researched in recent years in order to reduce the cutting temperature in ECMP, thus enabling the part quality, the tool life and the material removal rate achieved in ECMP at least equate or surpass those obtained in conventional machining. On the other hand, the reduction of cutting temperature by using these techniques is often superfluous and is adverse to the produced surface roughness as the work material tends to inherent brittle and hard property at low temperature. Open cooling system means the machining requires a constant cooling supply and it does not provide a solution for process condition feedback as well.This Ph.D. project aims to investigate the design and analysis of internally cooled cutting tools and their implementation and application perspectives for smart adaptive machining in particular. Circulating the water based cooling fluid in a closed loop circuit contributes to sustainable manufacturing. The advantage of reducing cutting temperature from localized heat at the tool tip of an internally cooled cutting tool is enhanced with the smart features of the tool, which is trained by real experimental data, to cognitively vary the coolant flow rate, cutting feed rate or/and cutting speed to control the critical machining temperature as well as optimum machining conditions. Environmental friendly internal micro-cooling can avoid contamination of generated swarf which can also reduce the cutting temperature and thus reduce tool wear, increase machining accuracy and optimize machining economics. Design of the smart cutting tool with internal micro-cooling not only takes into account of the environmental aspects but also justifies with its ability to reduce the machining cost. Reduction of production cost can be achieved with the lower consumption of cooling fluid and improved machining resources/ energy efficiency. The models of structural, heat transfer, computational fluid dynamics (CFD) and tool life provide useful insight of the performance of the internally cooled smart cutting tool. Experimental validation using the smart cutting tool to machine titanium, steel and aluminium, indicates that the application of internally cooled smart cutting tools in adaptive machining can improve machining performance such as cutting temperature, cutting forces and surface quality generated. The useful tool life span is also extended significantly with internally cooled smart cutting tools in comparison to the tool life in conventional machining. The internally cooled smart cutting tool has important implications in the application to ECMP particularly by overcoming the stigma of high uncontrollable cutting temperature with the absence of cooling fluid.Brunel Universit

An investigation on micro cutting mechanics: Modelling, simulations and experimental case studies

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University London.Micro cutting is becoming increasingly important since miniature and micro components/products have become more and more demanded in precision engineering applications and consumer goods in a daily life. Meanwhile, it has not been thoroughly investigated yet. Scientific understanding of the fundamentals in micro cutting mechanics and physics is vital for micro manufacturing of micro or miniature components and products. Consequently, the scientific investigation on micro cutting mechanics is critically needed, particularly on its key fundamental aspects on which a systematic approach and key enabling technologies are developed for micro manufacturing. Therefore, three key fundamental aspects of micro cutting mechanics have been identified for this PhD project and a comprehensive systematic research has been performed through both theoretical and experiment-based investigations. The three aspects of micro cutting mechanics mainly include dynamic stiffness investigation, innovative micro cutting force modelling, and the study on micro cutting heat, temperature and their partitioned distribution. All experiment-based investigations are undertaken on a diamond turning machine test rig supported with a fast tool servo (FTS) using different reconfigured experimental setups. The finite element (FE)-based analysis is conducted to further support the in-depth analysis on the micro cutting phenomena especially the modelling and simulation of micro cutting force and temperature. Accordingly, both micro cutting force modelling and micro cutting temperature are investigated using modelling and simulation supported by well-designed experimental cutting trials and validations.The investigation on dynamic stiffness in the micro cutting system is focused on its effects on the micro cutting process and its control strategies. The burrs formation and machining accuracy are explored in relation with control of the dynamic stiffness. Furthermore, the control algorithm for dynamic stiffness is developed accordingly in order to minimise burrs formation and stabilize the micro cutting accuracy.The micro cutting force modelling is performed based on specific cutting force, i.e. modelling the cutting force at the unit cutting length or area as coined as the amplitude aspect of the proposed cutting force modelling. The cutting force against a dynamically varied cutting time interval is proposed as the spatial aspect of the cutting force formulation. The amplitude aspect can provide the insight into the micro cutting phenomena particularly in relation with the chip formation and size-effects. The spatial aspect, using a on the wavelet transform (WT) technique and standard deviation analysis can render the dynamic behaviour of the micro cutting force, particularly representing the dynamic effects of the cutting process and its correlation with tool wear.The micro cutting temperature is investigated to formulate the scientific understanding of cutting temperature, heat and their partitioned distribution particularly at the tool-workpiece-chip interface zone in ultraprecision and micro cutting using a diamond cutting tool. The contribution to knowledge at this aspect is to represent the partitioned cutting heat in the micro cutting process and their different behaviours compared to the conventional metal cutting. The scientific approach to modelling micro cutting application (MMCA), i.e. based on modelling-simulation combined with experimental validation, is further evaluated and validated to illustrate the overall benefits of this research investigation through micro cutting of single crystal silicon (for ultraprecision machining of large-sized infrared devices). This approach is established in light of combining all the three aspects of the above investigation on micro cutting mechanics. The research results show the approach can lead to industrial scale advantages for ultraprecision and micro cutting but driven by the scientific understanding of micro manufacturing technology. The systematic investigation on dynamic stiffness control, micro cutting force modelling, micro cutting heat and temperature and their integrated approach can contribute well to the future micro cutting applications

Study on Gun Drilling Technology in CNC Machining

This document is the internship report of the Master in Product Design Engineering carried out at Tecnimoplás Lda. The company Tecnimoplás Lda is dedicated to manufacture of molds. They have an ability to make a small, medium and large size molds. Tecnimoplás is a company started in 1971 based in Marinha Grande, specialized in the service of mold. With this internship it was possible to get the industrial immersion that was the one of the objectives of the student for this stage. In the company after an initial inclosing, it was possible to develop work in the different equipment’s with different materials for mold in the company machines. This statement is a detailed description and analytical analysis with various processes to make a mold. In this process one of the main process is Deep Hole Drilling. It is also talking about the various types of tools used in deep hole drilling machines and also discuss about the various types of fixing system in deep hole drilling machines. This deep hole drilling is mainly used for Water and Oil circuit in the mold. This report also comprises of case study of Deep hole drilling process and the void formation in the parts of Deep hole drilling machines. This work also concluded that it is fundamental that the tools used in Deep Hole drilling, are used within the ranges of operation recommended by the tool’s manufacturers

Chip-controlled 3-D complex cutting tool insert design and virtual manufacturing simulation

Designing suitable tools for the turning operation is of vital interest to manufacturers. The tool inserts used nowadays adopt complex geometric shapes. A question facing many manufacturers is how to effectively design complex shaped tool inserts and how to prove the validity of such design. One of the important criteria for selecting inserts is the ability to control chip formation and chip breaking;The research work described in this dissertation attempted to bring innovation into the cutting tool insert design process by using feature-based modeling and by proposing a predictive chip model and integrating it into the design process. Such model integration makes the tool insert design a much more effective process and also enhances the decision-making required in insert design;A new 3-D kinematic chip model was developed to depict chip behavior in a complex groove insert. The model derived showed the analytical relationships between chip shape parameters and chip motion parameters. This dissertation explained how the kinematic model could be modified to take into account all possible 3-D complex groove shapes. A mathematical model was also developed from experimental data to serve the current need for cutting tool design;Other research work presented in this dissertation is the simulation of the machining process in a virtual environment. The virtual machining simulation can be of great benefit for researchers in manufacturing to use the platform as a testbed for product development and testing

Intelligent Systems

This book is dedicated to intelligent systems of broad-spectrum application, such as personal and social biosafety or use of intelligent sensory micro-nanosystems such as "e-nose", "e-tongue" and "e-eye". In addition to that, effective acquiring information, knowledge management and improved knowledge transfer in any media, as well as modeling its information content using meta-and hyper heuristics and semantic reasoning all benefit from the systems covered in this book. Intelligent systems can also be applied in education and generating the intelligent distributed eLearning architecture, as well as in a large number of technical fields, such as industrial design, manufacturing and utilization, e.g., in precision agriculture, cartography, electric power distribution systems, intelligent building management systems, drilling operations etc. Furthermore, decision making using fuzzy logic models, computational recognition of comprehension uncertainty and the joint synthesis of goals and means of intelligent behavior biosystems, as well as diagnostic and human support in the healthcare environment have also been made easier

Manufacturing code generation for rotational parts in a feature based product modelling environment

An important element for the integration of CAD/CAM is the representation and handling of data used during the design and manufacturing activities. The use of features and product modelling techniques bring a better handling of this data and provide CAD/CAM with an excellent platform for integration. The thesis explores the use of a predefined set of features in a product modelling environment for the design and machining of rotational components. Theword features in this research implies a set of functional, geometrical and technological information with a unique form. Those features are pre-defined and comprise of a limited number of elements which carry the information related to design and manufacturing activities. The thesis is divided into three main parts. The first part contains a review of topics related to the research e. g. group technology, component features, CAD/CAM and also contains a literature survey of related research works. In the second part the "features" are defined and presented. Also the product modelling environment is explained and the basic rule based procedures which are used to automatize the operation planning activities are presented. In the last part a description of the case-studies used for automatic NC code generation is presented followed by a discussion of the results. Lastly, the conclusions are drawn and ideas for further work presented