High speed twist drills are probably the most common of all metal cutting tools and also the least efficient. In this study, detailed research was undertaken into aspects of drill performance and ways in which drilling could be improved in short hole depths of up to two diameters. The work included an evaluation of twist drill geometry and grinding parameters. It was established that errors in point grinding lead to increased hole oversize and reduced drill life. A fundamental analysis was made to establish predictive equations for the drill torque and thrust using modified orthogonal cutting equations and empirical data. A good correlation was obtained between actual and predicted results. Two new techniques for extending twist drill life by the use of coolant feeding holes and also the application of titanium nitride coatings were evaluated. Both methods were found to have potential for improving drill performance. A completely new design of carbide tipped drill was designed and developed. The new design was tested and it compared favourably with two commercially available carbide tipped drills. In further work an entirely different type of drill point geometry was developed for the drill screw. A new design was produced which enabled the drilling time to be minimised for the low thrust forces that were likely to be used with hand held power tools.

Much of the geometrical data relating to engineering components and assemblies is stored in the form of orthographic views, either on paper or computer files. For various engineering applications, however, it is necessary to describe objects in formal geometric modelling terms. The work reported in this thesis is concerned with the development and implementation of concepts and algorithms for the automatic interpretation of orthographic views as solid models. The various rules and conventions associated with engineering drawings are reviewed and several geometric modelling representations are briefly examined. A review of existing techniques for the automatic, and semi-automatic, interpretation of engineering drawings as solid models is given. A new theoretical approach is then presented and discussed. The author shows how the implementation of such an approach for uniform thickness objects may be extended to more general objects by introducing the concept of `approximation models'. Means by which the quality of the transformations is monitored, are also described. Detailed descriptions of the interpretation algorithms and the software package that were developed for this project are given. The process is then illustrated by a number of practical examples. Finally, the thesis concludes that, using the techniques developed, a substantial percentage of drawings of engineering components could be converted into geometric models with a specific degree of accuracy. This degree is indicative of the suitability of the model for a particular application. Further work on important details is required before a commercially acceptable package is produced.

No description available.

In industry the colour of a gold alloy electrodeposit is checked by visual comparison with standard panels. The aims of the present work have been to access the application of spectrophotmetric techniques to the measurement of the colour of gold alloy electrodeposits and to examine the factors that influence the colour of thin deposits. The minimum thickness of deposit required to produce its final colour and completely hide the underlying substrate was measured and found to depend on the nature of the substrate, the plating solution and the operating conditions. Bright and matt electrodeposits were studied. The influence of alloying gold by adding copper, silver and indium to the plating solution were investigated. CIE chromaticity coordinates were calculated from spectrophotometric data using a computer programme written for the purpose. The addition of silver to a simple gold bath caused the colour of the deposit to change from yellow through green to near white in a smooth progression as the amount of silver in solid solution steadily increased. The colour of deposits formed when additions of copper were made was complicated by the formation of intermediate phases. À colour in the blue region of the spectrum was obtained in a few experiments investigating the influence of indium additions to the gold bath.

The internationally accepted Wolfson Heat Treatment Centre Engineering Group test was used to evaluate the cooling characteristics of the most popular commercial polymer quenchants: polyalkylene glycols, polyvinylpyrrolidones and polyacrylates. Prototype solutions containing poly(ethyloxazoline) were also examined. Each class of polymer was capable of providing a wide range of cooling rates depending on the product formulation, concentration, temperature, agitation, ageing and contamination. Cooling rates for synthetic quenchants were generally intermediate between those of water and oil. Control techniques, drag-out losses and response to quenching in terms of hardness and residual stress for a plain carbon steel, were also considered. A laboratory scale method for providing a controllable level of forced convection was developed. Test reproducibility was improved by positioning the preheated Wolfson probe 25mm above the geometric centre of a 25mm diameter orifice through which the quenchant was pumped at a velocity of 0.5m/s. On examination, all polymer quenchants were found to operate by the same fundamental mechanism associated with their viscosity and ability to form an insulating polymer-rich-film. The nature of this film, which formed at the vapour/liquid interface during boiling, was dependent on the polymer's solubility characteristics. High molecular weight polymers and high concentration solutions produced thicker, more stable insulating films. Agitation produced thinner more uniform films. Higher molecular weight polymers were more susceptible to degradation, and increased cooling rates, with usage. Polyvinylpyrrolidones can be cross-linked resulting in erratic performance, whilst the anionic character of polyacrylates can lead to control problems. Volatile contaminants tend to decrease the rate of cooling and salts to increase it. Drag-out increases upon raising the molecular weight of the polymer and its solution viscosity. Kinematic viscosity measurements are more effective than refractometer readings for concentration control, although a quench test is the most satisfactory process control method.

Thesis (Ph.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / The present work involves the study of a simplified atomic system to gain better understanding of controlling and manipulating Rydberg-like systems. Detailed simulations of the classical hydrogen atom have been carried out using, first, the nonrelativistic Lorentz-Dirac classical equation of motion for a charged point particle under the action of a Coulombic binding force, plus applied radiation, then progressing to include the effects of the classical electromagnetic zero-point (ZP) radiation spectrum. This work has been carried out under the guide of the theory called stochastic electrodynamics (SED). Many applications involving atoms in excited Rydberg states can be developed, based on the work described here, to aid in carefully controlled thin film deposition, ion implantation, etching, and sputtering in micro and nanoelectronics, as well as optical instrumentation related applications, via applied electromagnetic fields. The improved simulation code for the long-term numerical integration of non-linear differential equations for tracking particles, should be helpful for a number of other closely related areas. Specifically, investigations into astronomy, including the Kepler problem treated in satellite and planetary orbit simulations in celestial mechanics, as well as problems in such areas as atomic and molecular dynamic studies, may well find benefit from the investigations here. As shown in the present study, very nonlinear behavior occurs for such Rydberg-like system, making a numerical study of the system nearly essential. Little of this work has been explored before in the literature. Resonances, rapid transitions, very long decay times, all influenced by applied radiation, are described and analyzed in detail here. Such results are expected to have significant bearing on recent experiments reported in the literature on "kicked Rydberg" atoms. Moreover, as reported here, the ZP field was included in very lengthy numerical simulations, resulting in a very close comparison with the ground state of hydrogen as predicted by Schrodinger's wave equation. This last result helps to support SED in general, although certainly considerable more work needs to be done for a full confirmation, but in the process this result greatly aids simulating situations where SED is expected to hold very well. / 2031-01-01

<p>Manufacturing today is increasingly competitive and every organization around the world is looking to decrease costs. Maintenance costs generated an average of 28 percent of total manufacturing cost at the Fiat Chrysler Indiana Transmission Plant One in 2018, states Rex White, Head Maintenance Planner at Fiat Chrysler (2018). Maintenance is a supportive expense that does not generate a profit, which makes maintenance an attractive expense to decrease. The cost for components and skilled labor are expensive; however, the downtime is exponentially a larger threat to production cost. One most feared scenarios within a manufacturing facility is that one machine takes down several as it backs up the entire production process.</p><p>The three major types of maintenance are reactive, preventive, and predictive. The research project focused on applying the principles of predictive maintenance to the Fiat Chrysler facilities in Indiana. The report explains the techniques and principles of applying the technology currently available to reduce downtime and maintenance cost. The predictive maintenance procedures and saving are compared with reactive and preventive methods to determine a value of return. The report will examine the benefits of using the Internet of Things technology to create autonomous self-diagnosing smart machines. The predictive maintenance plan in this research illustration will introduce health check equipment used to implement longer lasting machine components. In conclusion, the project developed out an entire predictive maintenance plan to reduce downtime and maintenance costs.<br></p><p></p><br>

No description available.

This thesis comprises of studies based on the broad field of forensic analysis and the development of methods which can be applied to different matrices. The initial studies focus on the forensic determination of psychoactive drugs in hair matrix using newly deve1oped gas chromatography-mass spectrometry analytical methods. The second study focuses on the discrimination and matching of skid marks and rubber tyre analysis by using novel chemical analysis methods. This thesis reports the deve1opment and application of a series of innovative analytical methods: gas chromatography-mass spectrometry, inductively coupled plasma mass spectrometry, pyrolysis-gas chromatography-mass spectrometry and attenuated total reflection Fourier transform infrared spectroscopy. Gas Chromatography-Mass Spectrometric (GC-MS) methods for drug analysis routinely employ derivatising reagents. The aim of the first study was to develop a method for the analysis of two recreational drugs, delta-9-tetrahydrocannabinol (delta-9- THC) and cocaine in hair samples using GC-MS, without prior derivatisation, thus allowing the sample to be analysed in its original form. Ten hair samples, that were positive to ELISA analysis for either delta 9-THC and/or cocaine, were enzymatically digested, extracted and then analysed by gas chromatography-mass spectrometry. All samples measured contained delta 9-THC and one sample contained cocaine. The limits of detection (LOD) and quantification (LOQ) were 0.02 ng/mg & 0.05 rig/mg, respectively for cocaine and 0.015 ng/mg & 0.02 ng/mg, respectively for A9-THC. The wide detection window, ease of direct analysis by GC-MS, lower detection limits of un-derivatised samples and the stability of drugs using this technique offers an improved method of analysis. This experiment has been designed to develop an immunological screening test followed by a GC-MS confirmation method for the simultaneous analysis of delta 9- THC, THC-COOH, , OH-THC, cocaine, Benzoylecgonine (BZ), amphetamine (AP), methamphetamine (MA), in human hair, thus avoiding the significant factors responsible for drug degradation by acid and alkali hydrolysis and to obtain optimal recovery conditions. Enzymatic hair digestion was used to hydrolyse 18 Turkish samples using Proteinase K, Dithiothreitol and Tris HCl buffer. At the beginning, all 18 samples tested screened positive on ELISA, though analysis by GC-MS indicated that only 2 samples were positive for delta 9-THC and THC-COOH. Cross reaction lead to false positive results in the pre-screening step as a result of the degradation of the antibodies in the pre-coated ELISA microplate. Tyre rubber analysis Owing to an increase in the number of hit and run accidents, it is quite common for rubber traces to be left at the crime scene. The Forensic Scientist will have the task of analysing the tyre striation traces in order to identify the type of tyre involved in the accident. However, the tyre striations alone do not provide enough detail to show a high level of discrimination between different tyre manufacturers and individual models. In this study, Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FI‘IR) and pyrolysis GC-MS methods were developed to enable greater discrimination between different tyre rubber samples. Seventy elements were screened for each sample by ICP-MS in both collision cell mode and reaction cell mode. ATR-FTIR analysis indicated a low intra-variability (analysis of similar tyres) which demonstrated high precision of the technique, and also showed a large inter-variability between different manufacturers and models, which supports their high potential as indicators to be used for discrimination between different tyres manufacturers and models. Principal Component Analysis (PCA) was utilised to distinguish between the different tyres.

<p>The E-department at GETRAG All Wheel Drive in Köping have problems with the efficiency on parts of their production equipment. The equipment with the most significant efficiency problems are four automated multifunctional production cells that produces housing for rear drive units. The major part of the problem is the large amount of small stops that causes the low efficiency.</p><p>The department already worked with logging of interruptions and efficiency calculations before this project started. However this work was not done to the extent considered necessary for a systematic follow-up of the interruptions.</p><p>The aim of this paper is to point out a more effective and systematic way to work with logging of interruptions and the follow-up. In addition the equipment were studied with a method for efficiency calculation that – if used properly- is a more powerful and a visually better method than the one used by the company today.</p><p>As the initial current state analysis of the equipment was made a lack of documented knowledge about the equipment was discovered. In addition the efficiency appeared to be lower than the companies previously presented figures.</p><p>With the help of new methods for logging of interruptions and a deeper failure analysis the production equipment were studied for ten weeks. These studies showed that the department have big opportunities to a more effective and more profitable production. This can be done by reducing the chronicle interruptions through a more systematic work with continuous improvements.</p><p>On the basis of the performed studies and the theoretical references a new working method that is based on the commitment of all employees is presented. This method can be used by the E-department to work with continuous improvements in a more systematic way than today.</p> / <p>E-verkstaden på GETRAG All Wheel Drive i Köping har effektivitetsproblem i delar av sin utrustning. Störst problem har avdelningen med fyra automatiserade fleroperationsceller som bearbetar ämnen till slutväxelhus. Till största del är det den stora mängden småstopp som ligger till grund för den låga effektiviteten.</p><p>Avdelningen arbetade redan vid starten av detta examensarbete i viss mån med störningsloggning och effektivitetsberäkningar. Dock utfördes inte detta arbete i den utsträckning och med det djup som krävs för en systematisk uppföljning av störningar.</p><p>Syftet med detta arbete var att visa på ett effektivare och mer systematiskt sätt att arbeta med störningsloggning och uppföljningsarbete. Dessutom granskades utrustningen med en effektivitetsmätningsmetod som om den används rätt är en mer kraftfull och visuellt bättre metod än den som används av företaget idag.</p><p>Då en inledande nulägesanalys utfördes på den berörda produktionsutrustningen upptäcktes brister i avdelningens dokumenterade kunskaper kring utrustningen. Dessutom visade sig effektiviteten vara betydligt lägre än de tidigare redovisade resultaten.</p><p>Med hjälp av nya metoder för störningsloggning och en mer ingående uppföljning av felorsakerna studerades den valda utrustningen i tio veckor. Studierna påvisade att det finns stora möjligheter till effektivare och mer vinstgivande produktion genom att systematiskt arbeta bort de kroniska störningar som finns i produktionsutrustningen.</p><p>Utifrån studierna som utförts och de teoretiska referenserna presenteras ett arbetssätt baserat på allas delaktighet, som kan användas av E-verkstaden för att på ett systematiskt sätt arbeta med ständiga förbättringar i produktionen.</p>