Plastic injection molding is widely used in many industrial applications. Plastic products are mostly used as disposable parts or as portable parts for fast replacements in many devices and machines. However, mass production is always adopted as an ideal method to cover the huge demands and customers’ needs. The problems of warpage due to thermal stresses, non-uniform pressure distribution around cavities, shrinkage, sticking and overall products quality are some of the important challenges. The main objective of this work is to analyze the stress distribution around the cavities during the molding and demolding to avoid their effects on the product quality. Moreover, diagnosing the critical pressure points around and overall the cavity projection area, which is subjected to high pressure will help to determine the optimum pressure distribution and ensure filling all cavities at the same time, which is another significant objective. Computer-aided design (CAD) and CATIA V5R20 are adopted for design and modeling procedures. The computer-aided engineering (CAE) commercial software ABAQUS 6141 has been dedicated as finite element simulation packages for the analysis of this process. Simulation results show that stress distribution over the cavities depends on both pressure and temperature gradient over the contact surfaces and can be considered as the main affecting factor. The acceptable ranges of the cavity stresses were determined according to the following values: the cavity and core region temperature of 55–65 °C, filling time of 10–20 s, ejection pressure 0.85 % of injection pressure, and holding time of 10–15 s. Also, theoretical results reveal that the uniform pressure and temperature distribution can be controlled by adjusting the cavities layout, runner, and gate size. Moreover, the simulation process shows that it is possible to facilitate and identify many difficulties during the process and modify the prototype to evaluate the overall manufacturability before further investing in tooling. Furthermore, it is also concluded that tooling iterations will be minimized according to the design of the selected process

Among many analysis methods, sensitivity analysis is one of a significant method used for many engineering solutions in many applications like the major uncertainties, model validation, model refinement and decisions making. There are different challenges in optimization and improvement of engineering products, like products life, esthetical shape, weight and durability. The main objectives of this work are to optimize the shape geometry and increase the service life of the product by determining and then minimizing the stresses concentration through predicting the influence of any change in geometry to recommend the optimum design. Sensitivities measurement is normally calculated based on computational technique conjunction with direct differentiation method. In this work, Finite element software under ABAQUS/CAE code has been adopted for analysis and simulation. In ABAQUS, and by default; appropriate perturbation can be determine automatically depend on a heuristic algorithm by using central differencing method. In this work; rubber brace are used for analysis, and the main design parameters used to specify the product sensitivity of the final geometry are: product thickness, small fillets and modules of elasticity. A reasonable result has been estimated in terms of stresses and product dimensions. Due to nonlinearity behavior; the reduction in stresses concentration is about 9%, and the product fillet yields to new values with small increment due the variable mass scaling used in boundary conditions. As results of this analysis, the zones of high stress values are specified, and the most effecting parameters on this stresses are determined. It's concluded that this technique is useful for many features like contacts, viscoelasticity and also in nonlinear analyses. Even more, sensitivity analysis can used to develop and improve the design before any further analysis.

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The main objective of this paper is to study the effect of extrusion parameters (extrusion stresses and temperature) and die geometry, i.e. extrusion radius, on the extruded aluminum quality using FEM Simulation Technique. For this purpose, the general FEA Software ABAQUS was used to set up the finite element model of the warm aluminum extrusion in two dimensions (2D). Aluminum alloy Al-2014 was used as billet material, with 40mm diameter and 75mm length. The extrusion process was modeled as isothermal, which means that the billet material was preheated at a specific temperature and then pressured into the circular die, with extrusion ratio 3.3. Optimized algorithms for extrusion parameters were proposed regarding the concluded simulating results. The results showed that small die angles required higher extrusion load than large die angles. In all die geometry used, the deformation of aluminum billet, which is caused by shearing and compression stresses, happened in a small sectional area (bearing area). The results also showed that, the values of these stresses can increase or decrease depending on the die entrance angle and the die bearing length. To avoid the effects of these stresses on die dimensions; the hardness, material selection, and geometry should be well calculated. An axis-symmetrical 2D geometric model of the tooling and billet was constructed for the analysis. Data obtained from the FE model included die-work piece contact pressure, effective stress and strain and material deformation velocity. The correlation between the calculated and FEA data was obtained in this research.

Mechanical pipe sticking is the important reasons which has a direct impact on the drilling process efficiency. The problems of pipe sticking during drilling, and the other problems associated with this case is a crucial task that must be early identified to find the causing factors before any further action. The main objectives of this study are to predict and specify the main causes of these problems through modeling and simulation processes. Consequently, the (ANSYS Workbench/2019 R3) Commercial version has been adopted for this analysis purposes. This analysis have been carried out based on the actual interaction and contact between the active working parts to simulate the actual process. In this simulation process, the non-deformable parts like drill pipe, and wellbore sleeve are considered (Masters), while deformable parts are (slaves). Simulation results approved that the pipe stick happened due to high values of generation stresses. The plot of maximum induced stresses shows that the generated stresses in the interaction zone between the outer surface of the drilling pipe and mud are (15) % more than in the other zones. Also, the probability of sticking during drilling can be predicted according to the relation between the drill depth with time and drag forces. It’s concluded that for freeing the stuck pipe it’s very necessary to predict the problems from the beginning. This type of analysis can assure the percentage accuracy for stuck pipe prediction is more than (70) %.