الفهرس 
CHAPTER (1) Introduction and Literature ReviewOnly 14 pages are availabe for public view
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Abstract
The Egyptian production of machine tools is neglected for decades, this instigated a stagnation and a great lag between the Egyptian machine tools and those in the developed countries. This study introduces an integral strategy for the modification of milling machine. Finite Element Method (FEM) is introduced as an alternative tool for studying the model using ANSYS and SOLIDWORKS software instead of experimental testing which demands time, costs and efforts.
Most developed countries compete industrially for the production of high-precision products, which necessitates the improvement of the required machine tools. In this regard, the products should be produced with high precision and acceptable surface finish to avoid post-treatments and additional costs. Thus, machine tools have been considerably developed in modern countries over the last decades.
Conventional machine tools can be improved for producing accurate products associated with high economic productivity. This improvement can be achieved via machine structure design enhancement dealing with its static and dynamic performance requirements. The milling machine is selected for this study as it is one of the most important machine tools.
Many of the economic and technical problems of machining processes are caused directly or indirectly by the power consumed in metal cutting which is largely transformed into heat near the cutting edge of the tool. This study handles calculating the middle chip thickness, the power and cutting force acting on the tool of the milling process. The machine tool operator should select the appropriate required parameters for the cutting process such as middle chip thickness, power and cutting force to avoid the poor quality of the machining products and the undesired excessive heat and vibration. The required power and force for the cutting process in the milling machine can be calculated manually from the theoretical equations or the nomogram associated with each milling process. In this regard, effective and fast software is developed for quickly assisting the milling machine operators to select the
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appropriate milling parameters such as (feed, speed, depth of cut, etc.) which can be used for a certain power and cutting force.
The study aims to outline the proposed procedures and trends of machine tools modeling for predicting its efficient performance. For improving the milling machine performance, four different suggested modifications of the milling machine structure were presented in this thesis. These modifications concerned with reducing the machine base thickness. The reduced weight of its base was replaced with additional ribs to reinforce the machine column to resist the vibration problems. Dynamic, and static analysis of the structure were performed to evaluate the dynamic characteristics. The suggested modifications’ natural frequencies are higher than those of the original structure of the machine. Hence, these modified designs have higher mitigation to vibration.
An effective and fast software was created to design a multi-stage main gearbox of (12) output speeds. The mentioned software includes gears design, speeds chart, theoretical speeds, actual speeds, and errors between theoretical and actual speeds. The first step involved a complex manual calculation of main and feed gearboxes design. Furthermore, SOLIDWORKS and ANSYS software are employed for modeling and evaluating the dynamic characteristics of the milling machine’s main and feed gearboxes using its designed dimensions. Besides, the natural frequencies and mode shapes of the gearbox are presented.