An Investigation of the Shell Nosing Process by the Finite-Element Method. Part 1: Nosing at Room Temperature (Cold Nosing)

1982 ◽  
Vol 104 (3) ◽  
pp. 305-311 ◽  
Author(s):  
Ming-Ching Tang ◽  
Shiro Kobayashi
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Room Temperature ◽  
Moving Boundary ◽  
Thickness Distribution ◽  
The Finite Element Method ◽  
Forming Process ◽  
Finite Element Program ◽  
Strain Rate Effects ◽  
Element Method

The metal-forming process of shell nosing at room temperature was analyzed by the finite-element method. The strain-rate effects on materials properties were included in the analysis. In cold nosing simulations, the nine-node quadrilateral elements with quadratic velocity distribution were used for the workpiece. The treatment of a moving boundary in the analysis of nosing is discussed and successfully implemented in the finite-element program. FEM simulations of 105-mm dia. shells of AISI 1018 steel and aluminum 2024 were performed and solutions were obtained in terms of load-displacement curves, thickness distribution, elongation, and strain distributions. Comparisons with experimental data show very good agreement.

scholarly journals A numerical method of optimizing the stretch forming process for the production of panels

2019 ◽  
pp. 386-395
Author(s):  
К.С. Бормотин ◽  
А. Вин
Keyword(s):  
Finite Element Method ◽  
Optimal Control ◽  
Finite Element ◽  
Optimal Control Problem ◽  
Control Problem ◽  
Control Program ◽  
The Finite Element Method ◽  
Forming Process ◽  
Residual Deformations ◽  
Element Method

Рассматривается моделирование технологий обтяжки на прессе для изготовления обшивок двойной кривизны. Автоматизированное формообразование деталей требует разработки управляющей программы и электронной модели пуансона. Качество полученной детали будет зависеть от точности вычисленной и изготовленной формы оснастки, задающей упреждающую форму панели, и траектории деформирования листовой заготовки. При условии заданной оснастки ставится задача оптимального управления для поиска наилучшей траектории движения зажимов в оборудовании. Вводятся критерии оптимизации процессов деформирования, которые обеспечивают минимальную поврежденность и максимальные остаточные деформации. Вычисление критериев выполняется с помощью моделирования и анализа нелинейного деформирования панели с контактными ограничениями методом конечных элементов. Формулируется дискретная задача оптимального управления, которая решается методом динамического программирования. Алгоритмы численного метода, реализованные в пакете программ MSC.Marc, позволяют вычислить оптимальные параметры работы обтяжного пресса. Программная реализация алгоритма выполнена в последовательном и параллельном режимах. На основе вычислительных экспериментов показана эффективность параллельного расчета на кластере вычислительных машин. We analyze the stretchforming technology using a press to manufacture the doublecurvature shells. The automated shaping of parts requires the development of a control program and an electronic model of a punch. The quality of the part obtained depends on the accuracy of the calculated and manufactured tools that specify the anticipated shape of the panel and on the deformation path of the sheet. Under the condition of a given tooling, an optimal control problem is formulated to find the best trajectory of movement of the clamps in the equipment. Some criteria for deformation optimization processes are introduced to ensure a minimum damage and maximum residual deformations. The calculation of the criteria is performed with the aid of modeling and analyzing the panel nonlinear deformation with contact constraints by the finite element method. The problems of inelastic deformation are solved by the finite element method. A discrete optimal control problem is formulated and solved by the methods of dynamic programming. The algorithms are implemented using the MSC.Marc package and allow us to calculate the optimal parameters of the stretchforming press in serial and parallel modes. The obtained numerical results show the efficiency of parallel implementations on a cluster of computers.

Improvement of Die-Roll Quality in Compound Fine-Blanking Forming Process

2011 ◽  
Vol 337 ◽  
pp. 236-241 ◽  
Author(s):  
Xin Hua Huang ◽  
Hua Xiang ◽  
Xin Cun Zhuang ◽  
Zhen Zhao
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Material Flow ◽  
The Finite Element Method ◽  
Forming Process ◽  
Fine Blanking ◽  
Die Roll ◽  
The Relationship ◽  
Element Method

Nowadays, the compound fine-blanking forming process is one of the most important processes to produce complicate multifunctional parts without subsequent machining. However, the big die-roll occurs in the sharp area is a common problem in this process. In this paper, the method with negative punch-die clearance was proposed to solve this problem by comparing three feasible plans. In addition, the influence on the process with different value of the negative punch-die clearance was studied by the finite element method (FEM). The results of this study verified that the process with suitable value of the negative punch-die clearance can result in significant decrease of the die-roll size. The relationship between the material flow near the region of die-roll and the punch-die clearance was also clarified.

Modeling and Simulation of Vibration-Assisted Extrusion Tapping of Internal Thread with Finite Element Method (FEM)

2012 ◽  
Vol 498 ◽  
pp. 183-188 ◽  
Author(s):  
Yong Yi Li ◽  
Sheng Dun Zhao
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Material Flow ◽  
Internal Thread ◽  
The Finite Element Method ◽  
Forming Process ◽  
Effect Mechanism ◽  
Vibration Parameters ◽  
Selection Of ◽  
Element Method

This paper firstly introduces the principle and characteristic of traditional extrusion tapping of internal thread, elaborates the material flow law during tapping process. Then puts forward a novel process of vibration-assisted extrusion tapping of internal thread, explains the effect mechanism of vibration during extrusion tapping of internal thread. Finally, with the finite element method (FEM), the simplified model of extrusion tapping are built, and the simulation of thread forming process of traditional extrusion tapping of internal thread are conducted, furthermore, the characteristic and influencing law of different vibration parameters (include vibration frequency, amplitude and direction) of vibration-assisted extrusion tapping of internal thread are studied, and some practical results are obtained. The simulation results show that applying vibration to extrusion tapping of internal thread can reduce tapping torque and improve thread forming quality, the reasonable selection of vibration parameters are very crucial to this novel process.

Position and the Size of Drawbeads for Sheet Metal Forming with the Finite Element Method

2014 ◽  
Vol 607 ◽  
pp. 112-117
Author(s):  
Khemajit Sena ◽  
Surasith Piyasin
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Drawing Process ◽  
The Finite Element Method ◽  
Forming Process ◽  
Deep Drawing Process ◽  
Metal Forming Process ◽  
Element Method

This study aims to find a solution to improve the formability in a deep drawing process. For this purpose drawbeads were used to avoid wrinkles and ruptures. The finite element method was applied to simulate the 3D metal forming process using a die and drawbead. The drawbead amount, position, size and form were studied for their affects on the formability. 3 drawbead patterns with 3 different heights were examined. The simulation was performed for each drawbead pattern and each drawbead geometrical parameter and the failure elements were counted. The best pattern chosen was the pattern that resulted in the least failure elements.

Study on Hydraulic Deep Drawing of Square Cups

2014 ◽  
Vol 626 ◽  
pp. 334-339
Author(s):  
Te Fu Huang ◽  
Hsin Yi Hsien ◽  
Yan Jia Chen
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Deep Drawing ◽  
Thickness Distribution ◽  
The Finite Element Method ◽  
Experimental Apparatus ◽  
Punch Load ◽  
Simulation Results ◽  
Good Agreement ◽  
Element Method

The friction holding effect and the friction reducing effect occurring during Hydraulic Deep Drawing and the pre-bulging resulting in more plastic deformation on products are applied on sheet hydro-forming. For Hydraulic Deep Drawing of a square cup, the thickness distribution and the relation between the height and the pressure of pre-bulging are simulated with SPCC steels as the specimen by the finite element method. An experimental apparatus of sheet hydro-forming has been constructed to carry out the hydraulic deep drawing experiments of square cups. Experimental thickness distribution and punch load are compared with simulation results. Good agreement was found. The flow patterns of the circular and square blanks with the condition of being firmly pressed against the punch observed from the experiments are in agreement with the predicted results.Keywords:Hydraulic Deep Drawing, sheet hydro-forming, finite element method

Further Developments in Applying the Finite Element Method to the Calculation of Temperature Distributions in Machining and Comparisons With Experiment

1983 ◽  
Vol 105 (3) ◽  
pp. 149-154 ◽  
Author(s):  
M. G. Stevenson ◽  
P. K. Wright ◽  
J. G. Chow
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Temperature Fields ◽  
The Finite Element Method ◽  
Finite Element Program ◽  
Temperature Distributions ◽  
Wide Range ◽  
Metal Machining ◽  
Element Program ◽  
Element Method

The finite element program developed in previous work [1] for calculating the temperature distributions in the chip and tool in metal machining has been extended in its range of application. Specifically, the program no longer needs a flow field as input and it can accommodate a wide range of shear angle and contact lengths. An important feature of this paper is that temperature fields from the finite element method have been compared with temperatures obtained with a previously described metallographic method [7]. This is the first time these two techniques have been used for the same machining conditions and the comparisons are very good.

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