This master thesis deals with design of injection moulding technology for plastic holder of carbon brushes made of polycarbonate labelled Lexan 945A. The injection is performed into injection mould with hot runner system. Initially there is general study related to plastics and injection moulding technology. Further the study continues with injection moulds with hot runners and ends with computer analysis of injection moulding process. The designed injection mould for production of plastic holders is three-plate, double cavity mould with four hot nozzles and one parting plane, where one of the plates serves for mounting of the hot runner system inside the mould. This work contains part of the drawing documentation and item list of the injection mould. The selected injection moulding machine is Arburg Allrounder 370 U labelled 700-290 according to EUROMAP.

Diploma thesis is focused on injection molding and welding technology of plastic materials. First, in theoretical part, are commonly described polymer materials, following by description of welding, and multi-injection molding. There are closely described different methods for chosen part. Practical part is about comparison of method according differ criteria and application suitability. At the end of the thesis there is economic estimation of methods.

My thesis presents the process of electromagnet production, including how the process is organised. My goal is to improve these techniques by refining them. To obtain the required data, the company's records were extracted and measurements were taken directly from the manufacturing process. Through examination of the data, any processes which created financial or temporal deficits were identified. Conclusions were then offered to solve these problem areas. These mainly involve alterations to the machinery settings, the delivery of materials and the management of production.

The project elaborated in scope of engineering studies branch 2307. The project is submitting design of production technology of car emblem. Different manufacturing technologies have been compared based on study of technical literature. Most suitable technologies have been chosen such as pressure die casting, especially aluminum alloys and plastic injection molding. Plastic part is metal plated afterwards in order to get desired metal look. Part of this project is injection molding tool design inclusive technical, technological and economic analysis.

This thesis contains of theoretical part which deals with injection molding, properties of some polymer materials are included also. Design of plastic injection mold for cover of electronic device is presented in practical part. Manufacturing parameters and injection machine selection are specified with mold structure consideration. Production costs and the final price of the plastic part are calculated in economical evaluation.

Diploma thesis which is developed for the master’s degree program (M2I – K Mechanical engineering) presents a proposal solution for production technology plastic car headlins parts from polymer material PBT GF30. Literature review summarizes the findings of thermoplastic injection technology and the structural design possibility of injection molds. The paper examined two variants of the running system, which are suitable for production of injection molding components. Finaly, after technical - economic assessment, we came to the conclusion that the better option is to use the hot runner system. In the practical part is the specified product modeled by the help of 3D software and the injection mold was designed. The design was implemented by CATIA V5 R20. For the design and manufacture of injection mold were used normality from MEUSBURGER. For the chosen alternative technology of production were made calculations and was selected injection molding machine Electron 75 – 300 from FERROMATIC.

This master thesis deals with design of injection molding technology for plastic lamp shade made of polycarbonate labelled Lexan 925. The injection is performed into injection mold with hot runner system. Initially there is a general study related to plastic materials and injection molding technology. Further the study continues with technological solution of production of the lamp shade. The designed injection mold is two-plate, double cavity mold with two hot nozzles and is equipped with a thread-unscrewing machine. This thesis contains part of the documentation and item list of the injection mold, along with technical-economical evaluation of the developed solution.

Nowadays, the filling and solidification of macro-scale injection mouldings can be predicted using commercial CAE software. For micro-injection moulding, the conventional tools do not work for all process conditions. The reasons might be the lack of high quality database used in the simulation and the improperly specified boundary conditions which do not reflect the real state in the cavity. Special aspects like surface tension or "size dependent" viscosity might also be responsible for the inaccuracy of the simulations. In this paper, those aspects related to the boundary conditions were taken into consideration, especially the thermal contact behaviour and the melt compression in the barrel which affects not only the temperature of the melt due to the compression heating, but also reduces the actual volume rate in the cavity. It can be shown that the heat transfer coefficient between the melt and the mould wall has a significant influence on the simulation results. In combination with precise material data and considering the reduction of the volume rate due to the melt compression in the barrel, the heat transfer coefficient may be quantified by means of reverse engineering. In general, it decreases when either the cavity thickness or the injection speed increases. It is believed that a pressure dependent model for the heat transfer coefficient would be more suitable to describe the thermal contact behaviour in micro injection moulding. The melt compression in the barrel affects definitely the filling behaviour and subsequently the heat transfer in the cavity as well, which is especially true for micro parts of high aspect ratio.

One portion of this work was concerned with injection molding pregenerated microcomposites composed primarily of poly(ethylene terephthalate) (PET) as the matrix and HX1000 as the thermotropic liquid crystalline polymer (TLCP). Several factors were examined to maximize the mechanical properties of these composites, including injection molding temperature, matrix viscosity, and nozzle tip exit diameter. In addition, concentrated strands of HX1000/PET (50/50 wt%) were diluted using both an injection molding grade of PET and an injection molding grade of PBT. From this work, it was determined that the best mechanical properties were produced when the microcomposites were processed at the lowest injection molding temperatures, diluted with PBT, and injection molded using a large nozzle tip exit diameter. The pregenerated microcomposite properties were compared against theoretical predictions as well as glass-filled PET. It was found that the pregenerated microcomposites had tensile moduli of approximately 70% of theoretical expectations in the machine direction. Additionally, the comparisons against glass-filled PET revealed that at the same weight fraction of reinforcement, the pregenerated microcomposites had lower properties. Still, the composites were found to have smoother surfaces than glass-filled PET and at temperatures up to 150° C the storage and loss moduli of the pregenerated microcomposites were similar to those of glass filled PET. It was concluded that if the theoretically expected levels of reinforcement could be attained, the pregenerated microcomposites processing scheme would be a viable method of producing light weight, wholly thermoplastic composites with smoother surfaces than are obtained with glass reinforcement. An additional focus of this research was to evaluate the ability to modify the crystallization behavior of a high melting TLCP (HX6000, Tm = 332° C) with a lower melting TLCP (HX8000, Tm = 272°C). It was found that it was possible to tailor the crystallization behavior of these TLCP/TLCP blends by varying the weight fraction of each component, as determined by rheological cooling scans and differential scanning calorimetric cooling tests. Based on the analysis of these TLCPs at the maximum injection molding temperature of 360° C, it was speculated that they had reacted with one another. / Ph. D.

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