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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Operating policies for adaptivce quality control and their application to machining processes

Dalal, Jayesh Govindlal. January 1970 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
12

A statistical and economic analysis of the optimum metal-cutting conditions

Ermer, Donald S. January 1966 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1966. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
13

Modeling haptics for virtual cutting embedded in CAD

Kate, Hrishikesh, January 2007 (has links) (PDF)
Thesis (M.S. in mechanical engineering)--Washington State University, December 2007. / Includes bibliographical references (p. 91-94).
14

Laser perforation for computer paper /

Gattuso, Claude F. January 1989 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1989. / Includes bibliographical references.
15

Applied rock cutting : a study of partial face disc cutting with blunt disc cutters /

Schmidt, Stuart. January 2005 (has links) (PDF)
Thesis (Ph.D.) - University of Queensland, 2005. / Includes bibliography.
16

High speed cutting and electric discharge machining as complementary processes in the die and mould industry

Treurnicht, N. F. 04 1900 (has links)
Thesis (MScEng) -- Stellenbosch University, 2003. / ENGLISH ABSTRACT: High Speed Cutting (HSC), specifically milling is a significant contemporary development in machining. The Die and Mould industry is experiencing a difficult business climate. There is competitive pressure for shorter lead times and lower prices. Companies worldwide, are under financial pressure, to meet the challenges of a globalised business environment. The conventional position of milling and Electric Discharge Machining (EDM / Erosion) is discussed with the proposal to use HSC and EDM as complementary processes. Among new developments the progress in computer infrastructure is prominent. There is also a paradigm shift that should be made from experience based process planning to modern, up to date knowledge based process planning. High Speed Cutting is now a mature process capable of acceptable process security. The examples detailed include crankshaft-forging tooling, injection moulding tooling and powder sintering tooling. A process chain is proposed for the complementary HSC / EDM process with estimated illustrative time saving over the conventional EDM dominated process. HSC will be the first process removing the bulk of the material, finishing as far as possible and with EDM finally machining the features that will be difficult or impossible with HSC. To facilitate the use of the complementary processes a decision model to determine the crossover point between HSC and EDM is proposed. The decision model is firstly presented as a flow diagram to determine whether the task is a candidate for HSC only, EDM only, or the complementary HSC / EDM process. The key parameters e.g tool H d ratio are variables. This is in order that the flow diagram may be adapted to a specific machine tool infrastructure and expertise level in a company. The second part is a HSC machining time estimation model. The time is estimated per segment roughed, semi-finished, or finish machined. The model is in an empirical form with constants that can be adapted to the practices of a specific company. It is intended that the constants also be periodically revised to reflect the development in HSC expertise that will occur during the use HSC in the company. The model is practically evaluated with a case study, including the detail steps, not included in the model. Conceptual guidelines are given for software implementation. It is concluded that HSC and EDM are suitable complementary processes. It is a necessary prerequisite to use pallets to avoid multiple set-ups. Complementary HSC and EDM is especially appropriate for the gradual deployment and skill development for HSC. HSC and complementary HSC / EDM is considered the opportunity for companies to make a major breakthrough in lead time and operating expense if the necessary pallet/fixturing equipment, CAx infrastructure and human capability is available. / AFRIKAANSE OPSOMMING: Hoe Spoed Masjinering (HSC), spesifiek frees is ‘n betekenisvolle ontwikkeling in masjinering. Die Gereedskap en Gietvorm bedryf ervaar ‘n moelike besigheidsklimaat. Daar is kompeterende druk vir korter lewertye en laer pryse. Maatskappye wereldwyd is onder finansiele druk om in die geglobaliseerde besigheidsmilieu te presteer. Die posisie van frees en Elektriese Ontladingsmasjinering (EDM / Vonkerosie) word bespreek met die voorstel om HSC en EDM as komplementere prosesse te gebruik. Onder die nuwe ontwikkelings is daar prominente vooruitgang in rekenaarinfrastruktuur. Daar is ook ‘n paradigmaverskuiwing nodig van ondervinding gebaseerde na op datum kennis gebaseerde proses beplanning. HSC is nou ‘n ontwikkelde proses met voldoende prosessekerheid. Die voorbeelde sluit krukas smee gereedskap, inspuitgiet gereedskap, en poeier-sinter persgereedskap in. ‘n Prosesketting word voorgestel vir die komplementere HSC / EDM proses met ‘n beraamde illustratiewe tydbesparing oor die konvensionele EDM gedomineerde proses. HSC sal die eerste proses wees wat die meerderheid van die materiaal verwyder en oppervlaktes so ver as moontlik afwerk, met EDM wat die finale afwerking doen en ook die masjinering wat vir moeilik haalbaar of onmoontlik is vir HSC. Om die gebruik van die komplementere prosesse te fasiliteer, word ‘n beluitnemingsmodel vir die oorgangspunt tussen HSC en EDM voorgestel. Dit word eerstens as vloeidiagram gebruik om die taak te klassifiseer vir HSC alleen, EDM alleen of vir komplementere HSC en EDM. Die sleutelparameters, bv die beitel 116 verhouding, is veranderlikes. Dit is sodat die vloeidiagram aangepas kan word by ‘n spesifieke masjienvermoe en ‘n kundigheidsvlak in ‘n maatskappy. Die tweede deel is ‘n HSC masjineringstyd model. Die tyd word beraam per segment uitgerof, afgewerk, of finaal afgewerk. Die model is in empiriese vorm met konstantes wat kan aangepas word by die praktyke van ‘n firma. Dit is die bedoeling dat die konstantes periodiek aangepas word om die ontwikkeling te weerspieel wat in die maatskappy plaasvind. Die model word prakties evalueer met ‘n gevallestudie, insluitend die detailstappe, wat nie in die modelformulering ingesluit is nie. Konseptuele riglyne word gegee vir programmatuur implementering. Die gevolgtrekking word gemaak dat HSC en EDM geskikte komplementere prosesse is. Dit is ‘n voorvereiste om pallette te gebruik om veelvuldige opstellings te vermy. Komplementere HSC / EDM is veral toepaslik om HSC geleidelik in ‘n firma te ontplooi en kundigheid te bou. Die HSC / EDM kombinasie word ook die geleentheid geag vir firmas om ‘n deurbraak te maak in lewertyd en bedryfsuitgawes as die nodige pallettoerusting, CAx infrastruktuur en menslike vermoe beskikbaar is.
17

Application of thin film PRTD's for the monitoring of cutting tool temperature during turning

Pifer, Mark T. 18 August 2009 (has links)
A tool condition monitoring system will reduce machine downtime, eliminate tool/workpiece destruction, and maximize tool life. Several of the cutting tool failure modes are cutting temperature-dependent. One of the cutting parameters to be monitored is the cutting temperature. On-line cutting tool temperature monitoring has been addressed with a variety of techniques, from work-tool thermocouples to embedded thermocouples to infrared radiation technology. However, these methods are not durable and robust enough to provide quick, accurate results from a production environment. The objective of this research work was, therefore to investigate the applicability of a thin film Platinum Resistance Temperature Detector (PRTD) sensor in the monitoring of cutting tool temperature for a turning tool. The thin film PRTD offers a small size, industrially durable method of monitoring cutting tool temperature with a quick response time. The sensor is placed under the cutting tool insert near the tool nose and is spring-loaded to ensure intimate contact. The sensor's output was correlated to those of a thermocouple, located at the nose of the insert and compared to estimated cutting temperatures using existing empirical models. Both sensor's were calibrated using a torch as an infinite heat source. Experimental results obtained under different cutting conditions indicate a high potential for the use of the thin film PRTD sensor for on-line cutting temperature monitoring in an industrial setting. / Master of Science
18

Low order autoregressive-moving average stochastic models and their use for the characterization of abrasive cutting tools

Stralkowski, Casimir Michael, January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1968. / Typescript. Vita. Description based on print version record. Includes bibliographical references (leaves 253-255).
19

A finite element analysis of pinion shaped spur gear teeth

Rhomberg, Edward W. January 1984 (has links)
An analysis of the effects of gear shaping with a pinion cutter upon the geometry and root stresses in external spur gears using the finite element method is given. The models analyzed have the shape of a ring with three teeth. The middle tooth is loaded and load sharing has been assumed. Thirty-five finite element models were used for the computation of stress concentration factors in pinion shaped gear teeth. The results for pinion shaped teeth are compared to those results obtained when shaping with a hob. The Dolan and Broghamer stress concentration factor was also calculated for comparison with the results from finite element analysis. The difference in the two was not more than 8%. The results from finite element analysis have been condensed into an empirical expression which gives the stress concentration factor as a function of the dedendum of the pinion, the numbers of teeth on the pinion and cutter, and the number of teeth on the mating gear. A comparison of the bending stress in the root of a tooth shaped by standard pinion and hob cutters indicated no appreciable differences in strength. / M.S.
20

Разработка методов повышения точности преобразователей вращательного движения в поступательное для систем отсчета перемещений рабочих органов станков с ЧПУ : магистерская диссертация / Development of methods for precision improvement of rotary motion converters into translational motion of reference systems for the movement of movable operating element of CNC machines

Тулепова, К. В., Tulepova, K. V. January 2022 (has links)
В данной магистерской диссертации представлены результаты разработки методов повышения точности преобразователей вращательного движения в поступательное для систем отсчета перемещения рабочих органов станков с ЧПУ, что и является целью выпускной квалификационной работы. Актуальность темы обусловлена тем, что точность машин и механизмов является основной характеристикой их качества. Традиционные механические передачи (зубчатые, реечные и др.) имеют широкое применение во всех отраслях машиностроения. Требования к точности изготавливаемых деталей существенно ужесточаются, поэтому необходимо непрерывно совершенствовать методы повышения точности передач. Научная новизна обусловлена разработкой новых методов повышения точности систем отсчета перемещений путем уменьшения или ликвидирования кинематических погрешностей и погрешностей от износа преобразователей вращательного движения в поступательное. Рассмотрены элементы, применяемые при построении современных систем отсчета перемещений и возникающие в них погрешности. Проведен анализ существующих методов уменьшения кинематических погрешностей и погрешностей от износа преобразователей вращательного движения в поступательное. На его основе разработаны: метод отсчета перемещений рабочего органа станка с компенсацией погрешностей ходового винта; метод снижения износа передачи винт-гайка скольжения; метод снижения износа передачи винт-гайка качения; метод отсчета перемещений рабочего органа станка с коррекцией кинематических погрешностей рейки; метод снижения износа зубчато-реечной передачи; насос, предназначенный для использования при реализации перечисленных методов. В ходе работы над магистерской диссертацией было подано шесть заявок на изобретения. В результате было получено пять патентов: патент на изобретение №2750575 «Насос шестеренный реверсивный», патент на изобретение №2756797 «Передача винт-гайка качения», патент на изобретение №2764105 «Зубчато-реечный привод подачи металлорежущего станка с ЧПУ», патент на изобретение №2768807 «Устройство отсчета перемещений рабочего органа машины с ходовым винтом» и патент на изобретение №2767381 «Передача винт гайка скольжения». На рассмотрении в ФИПС находится заявка на изобретение №2021114570 «Зубчато-реечный привод подачи рабочего органа тяжелого крупногабаритного металлорежущего станка». / This master's thesis presents the results of the development of methods for precision improvement of reference systems for the movement of movable operating element of CNC machines, which is the purpose of the final qualifying work. The relevance of the topic is due to the fact that the precision of machines and mechanisms is the main characteristic of their quality. Traditional mechanical gears (gear, rack and pinion, etc.) are widely used in all branches of mechanical engineering. The requirements for the precision of manufactured parts are significantly tightened, so it is necessary to continuously improve methods for improving the precision of transmissions. The scientific novelty is due to the development of new methods for improving the precision of displacement reference systems by reducing or eliminating kinematic errors and errors from wear of rotary motion converters to translational. The elements used in the construction of modern displacement reference systems and the errors arising in them are considered. The analysis of existing methods for reducing kinematic errors and errors from wear of rotary motion converters to translational motion is carried out. Based on it, the following methods have been developed: the method of counting the movements of the movement of movable operating element of the machine with compensation of errors of the lead screw; the method of reducing the wear of the transmission screw-nut sliding; the method of reducing the wear of the rolling screw-nut transmission; the method of counting the movements of the movement of movable operating element of the machine with correction of kinematic errors of the rail; the method of reducing the wear of rack and pinion transmission; the pump, designed for use in the implementation of the above-mentioned methods. During the work on the master's thesis, six applications for inventions were submitted. As a result, five patents were obtained: patent for invention No. 2750575 "Reversible gear pump", patent for invention No. 2756797 "Rolling screw-nut transmission", patent for invention No. 2764105 "Rack-and-pinion feeding drive of CNC metal cutting machine", patent for invention No. 2768807 "Device for counting the movements of the operating member of a machine with a drive screw" and patent for invention No. 2767381 "Sliding screw-nut gearing". The application for invention No. 2021114570 "Rack-and-pinion feeding drive of the operating member of a heavy large-sized metal-cutting machine" is under consideration in the federal institute of industrial property.

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