The mechanical grinding processes is the most popular way to fabricate the end face of optical fibers, although there are some other methods like chemical etching and leaser machining. In cases of fabricate the wedge type and wedge-cone type optical fiber end faces, the mechanical grinding is the typical way. Professor Y. C. Tsai¡¦s research group has successfully fabricated the optical fiber with elliptical-cone-type end-face in a single grinding process by adopting a mechanism with eccentric mass on the commercial optical fiber grinding machine. In this study, a torque motor is equipped on the commercial optical fiber grinding machine for controlling the normal pressure between the optical fiber and the grinding film during the grinding process. While the optical fiber rotating, the normal pressure, as well as the material removed rate and the final shape of the optical fiber, can be controlled in different periodical mode shapes by applying different voltages with different periodical mode shapes. The merit of this system is its capability of fabricating fiber with elliptical-cone-shape and polygon-cone-shape (polyhedron-tip) end faces in a single grinding process that will increase the efficiency and the accuracy of grinding. It is believed the grinding machine system developed in this study can be successfully applied for fabricating the optical fiber lenses as well as different types of micro probes for other applications.

No description available.

In this study, the new predictive model for the micro-grinding process was developed by consolidating mechanical and thermal effects within the single grit interaction model at microscale material removal. The size effect of micro-machining was also included in the proposed model. In order to assess thermal effects, the heat partition ratio was experimentally calibrated and compared with the prediction of the Hahn model. Then, on the basis of this predictive model, a comparison between experimental data and analytical predictions was conducted in view of the overall micro-grinding forces in the x and y directions. Although there are deviations in the predicted micro-grinding forces at low depths of cut, these differences are reduced as the depth of cut increases. On the other hand, the optimization of micro machine tools was performed on the basis of the proposed design strategy. Individual mathematical modeling of key parameters such as volumetric error, machine working space, and static, thermal, and dynamic stiffness were conducted and supplemented with experimental analysis using a hammer impact test. These computations yield the optimal size of miniaturized machine tools with the technical information of other parameters.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1968. / Typescript. Vita. Description based on print version record. Includes bibliographical references (leaves 253-255).

As moagens autógena (AG) e semiautógena (SAG) mostram-se como opções cada vez mais consideradas na seleção de novos circuitos de cominuição. A flexibilidade de operação, assim como a combinação de grandes capacidades de processamento e altas relações de redução obtidas, são algumas das vantagens destes circuitos. Este trabalho procurou descrever o método utilizado na condução de ensaios de moagem semiautógena em escala piloto e de caracterização tecnológica, empregando o minério de ouro da Rio Paracatu Mineração S/A (RPM). A moagem semiautógena foi investigada considerando diferentes condições de operação e às especificidades do minério da RPM. Foram conduzidos 69 ensaios em planta piloto que permitiram o estudo do efeito das variáveis de operação sobre parâmetros de moagem SAG, como taxa de processamento, consumo energético específico, qualidade do produto, entre outros. As informações obtidas na campanha de ensaios em planta piloto e nos trabalhos de caracterização das amostras mostraram-se consistentes e fundamentaram o dimensionamento e projeto do circuito de Expansão da RPM, com capacidade de processamento adicional de 41 Mtpa. / The autogenous (AG) and semi-autogenous (SAG) mills have increasingly been considered options in the selection of new comminution circuits. The flexibility of the operation, as well as the combination of high processing capacity and high reduction rates obtained, are some of the advantages of these circuits. This study sought to describe the method used in conducting semi-autogenous grinding pilot plant and technological characterization, using the gold ore from the Rio Paracatu Mineração S/A (RPM) mine. The semi-autogenous grinding was investigated considering different operating conditions and specific characteristics of the ore from the Rio Paracatu Mineração mine. Were conducted 69 tests in a pilot plant that enabled the study of the effects of the operating variables of the SAG grinding parameters such as processing rates, specific energy consumption, product quality, among others. Information obtained in the test campaign of the pilot plant and the characterization work of the samples were consistent and supported the design and project of the circuit of the expansion of the Rio Paracatu Mineração mine, with additional processing capacity of 41 Mtpy.

Grinding aids are surface active substances, wich separate particles of milled substance and prevent their reaglomeration.

This work deals with the thermal load during cut-off grinding of high-strength bearing rings. Linear cut-off operations lead to a high rise in temperature over the cutting process. These leads, together with the limited material volume, in a heat build-up and the resulting grinding burn. The aim of this work was to prevent this head build-up by using two-axis cut-off operations. Therefore, known methods were theoretically considered and from this, alternative two-axis strategies were determined. For testing, experiments were carried out on a test set-up developed in this work. The tests showed that the two-axis strategies lead to significantly reduced temperatures, as well as non-grinding burn and partially burr-free cutting surfaces. However, the two-axis methods lead to increased process times, which is why approaches for their optimization have been discussed.

My diploma thesis solves project of grinding angle box unit for vertical boring and turning machine which extends technological possibilities of vertical lathe SKD 40/47D. The submitter ČKD Blansko Holding, a.s. demanded to work out assembly drawing, 3 construction drawings and necessary calculations. Spindle drive of grinding unit is implemeted by the aid of engine which is deposit in the sliding machine. Chucking equipment is realised with standart system which is used by ČKD Blansko.

This diploma thesis solves grinding box unit for vertical boring and turning machine for ČKD Blansko. For fixing is used standard fixing system used in ČKD Blansko. Spindle is drived by engine placed in slide ram. Engine can be also used for milling box unit. Grinding box unit must stand operating load. Using of automatic balancing system is also solved in this project.

The aim of the diploma thesis was to analyze qualitative outages in the production of gears for a gear pump and to minimize them. The largest amount of outages was caused by the burning of the surface during face grinding. After analyzing the current state of production there were created some suggestions to avoid this issue. Also there was found some space to speed up the whole process. Suggestions to eliminate burning have been tested with minimal impact on production. The reduction of outages for burned surface was achieved and also the cycle time was shortened. Those suggestions will be implemented in serial production.