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A majority of plastic items are produced by injection moulding process. Experiments are conducted to find out the residual stresses developed in mould due to cooling and voids created in the mould cavity due to improper filling of plastic (polymer), therefore producing a weak and objectionable component. There are numerous methods to find voids in the end product, one of them is measuring void rates using optical microscope. Another way of identifying the residual stress is by simulating specimen part in analysis software and studying flow pattern of heat from runner point to end part of component. Also, when the mould is set for cooling procedures, the simulation of cooling from its highest temperature to room temperature could be simulated in a computer to study the cooling pattern. The volume in part where cooling happens fastest relative to other surrounding parts may result in stresses, called residual stress. This phenomenon also leads to redundant results such as warpage, sink marks and weld lines which are extremely costly problems to fix once the mould is in production environment. / Plastic parts that require tight tolerance may warp out of tolerance even if made by the most experienced mould makers. New companies may not have the expertise to start making moulds correctly for even the simplest parts. A lot of capital is invested in moulds and in cost of making parts, and much of the money spent on making moulds goes into reworking them. In order to avoid the huge cost spent on reworks, the mould can be made right the first time. / This objective could be achieved, by the use of Finite Element Analysis (FEA), and advantage of software simulation to study the thermal flow patterns, from this shrinkage due to rapid cooling of plastic injected parts can be predicted. Use of ANSYS to model, mesh and analyse simple plastic components is the aim of this project. / Thesis (MEngineering)--University of South Australia, 2005.

Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains xiii, 101 p. : ill. (some col.). Includes two zip files of TIF images. Includes abstract. Includes bibliographical references (p. 93-94).

Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references. Also available via the Internet.

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 136-139).

Thesis, PlanB (M.S.)--University of Wisconsin--Stout, 2006. / Includes bibliographical references.

Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references (leaves 82-85). Also available in electronic version.

Thesis (MTech (Mechanical Engineering))--Peninsula Technikon, 1999 / Since 1996, a team at the Centre for Research in Applied Technology (CRATECH) at Peninsula Technikon, under NRF sponsorship and with industrial co-operation, has been involved in the simulation of Non-Newtonian flow behaviour in industrial processes, in particular, injection moulding of polymers. This study is an attempt to deal with some current issues of Non-Newtonian flow, in small areas, from the viewpoint of computational mechanics. It is concerned with the numerical simulation of Non-Newtonian fluid flows in mould cavities with re-entrant corners. The major complication that exists in this numerical simulation is the singularity of the stresses at the entry of the corner, which is responsible for nonintegrable stresses and the propagation of solution errors. First, the study focuses on the derivation of the equations of motion of the flow which leads to Navier- Stokes equations. Thereafter, the occurrence of singularities in the numerical solution of these equations is investigated. Singularities require special attention no matter what numerical method is used. In finite element analysis, local refinement around the singular point is often employed in order to improve the accuracy. However, the accuracy and the rate of convergence are not, in general, satisfactory. Incorporating the nature of singularity, obtained by an asymptotic analysis in the numerical solution, has proven to be a very effective way to improve the accuracy in the neighborhood of the singularity and, to speed up the rate of convergence. This idea has been successfully adopted in solving mainly fracture mechanics problems by a variety of methods: finite difference, finite elements, boundary and global elements, and spectral methods. In this thesis, the singular finite elements method (SFEM), similar in principle to the crack tip element used in fracture mechanics, is proposed to improve the solution accuracy in the vicinity of the singular point and to speed up the rate of convergence. This method requires minor modifications to standard finite element schemes. Unfortunately, this method could not be implemented in this study due to the difficulty in generating the mesh for the singular element. Only the standard finite element method with mesh refinement has been used. The results obtained are in accordance with what was expected.

This thesis deals with the optimization of the production technology of the cap tube made by injection molding. Series production is set at 5 000 000 units per year; the minimum time of the production is 5 years. A literary study is developed, focusing on the technology of injection molding in molds including the possibilities of the optimization of the production by changing the structure of the mold. The practical part of the thesis is devoted to the optimization of existing mold with cold runner system for the production of the cap tube, using the hot runner system supplied by Synventive. The change of the structure of the mold involves changing the three plate mold to a two plate mold. It is about changing the fixed part of the mold in which the hot runner system is placed; it is composed of standards parts of the company HASCO. Based on the technological parameters the injection machine Krauss Maffei KM 80-380 CX is chosen. There is a technical-economical evaluation of the optimization of the production by using the hot runner system at the end of the thesis.

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