scholarly journals Application of the Method of Coordinate Grids for Experimental Study of Pipe Extrusion Process With Lateral Metal Flow

2018 ◽  
Vol 7 (3) ◽  
pp. 49
Author(s):  
Kosmatskiy Yaroslav Igorevich ◽  
Al-Jumaili Mohammed Jasim Mohammed ◽  
Al-Khuzaie Ahmed Saleem Oleiwi

The paper presents the results of an experimental study of pipe extrusion process with lateral flow using the method of coordinate grids. The calculation of the forming operation is made for extrusion process stages.

2018 ◽  
Vol 7 (3) ◽  
pp. 58
Author(s):  
Kosmatskiy Yaroslav Igorevich ◽  
Al-Khuzaie Ahmed Saleem Oleiwi ◽  
Al-Jumaili Mohammed Jasim Mohammed

The paper presents the results of an experimental study of the pipe extrusion process using the method of coordinate grids. The estimation of influence of separate conditions of friction on the contact surfaces of the deformable material and the pressing tool on metal flow pattern. The calculation of the forming operation is made for extrusion process stages.


2000 ◽  
Vol 6 (S2) ◽  
pp. 954-955
Author(s):  
Steven R. Claves ◽  
Wojciech Z. Misiolek ◽  
William H. Van Geertruyden ◽  
David B. Williams

Electron Backscattering Diffraction (EBSD) is an important tool for analyzing the crystal grain orientation of a microstructure and can be used to formulate conclusions about microtexture, texture determined from individual grains. This technique has been used to study a 6xxx series aluminum alloy's response to the deformation of the extrusion process. Extrusion is the process by which a billet of material is forced, under high pressure, through a die. The material undergoes a significant decrease in cross sectional area, and is formed into a shape equivalent to the geometry of the die orifice. Different bearing lands are shown in shown in Figure 1. These surfaces form the part, and are designed to control the metal flow making it uniform through the die, thus yielding good mechanical properties. This research was focused on the resultant microstructure. The shaded regions of Figure 2 show the two surface regions where EBSD measurements were taken.


2007 ◽  
Vol 344 ◽  
pp. 947-953 ◽  
Author(s):  
K. Kawai ◽  
H. Koyama ◽  
T. Kamei ◽  
W. Kim

Boss forming, which is sometimes called hub forming, has attracted its attention as an environment-friendly rotary forming process to form a circular plate with a hole into a boss shape. An experimental study was conducted to survey the technological possibility of boss forming. Boss forming of A1050-O commercially pure aluminum plate of 10 mm thickness was carried out at room temperature under various working conditions. The effects of the working conditions on the metal flow in boss forming were clarified experimentally.


2010 ◽  
Vol 148-149 ◽  
pp. 1684-1688 ◽  
Author(s):  
Hao Chen ◽  
Guo Qun Zhao ◽  
Cun Sheng Zhang ◽  
Jiang Wei Liu

The extrusion die is of great importance in the quality control of profile production. Yet in practice, the design of extrusion die is mainly dependent on the experience and intuition of die designers, which is difficult to guarantee product quality and productivity. In this paper, a numerical model was developed based on HyperXtrude with an attempt to investigate the effects of the shape of the welding chamber on metal flow and weld quality. The porthole dies with different steps of welding chamber were designed and applied to extrude an identical profile. Numerical results showed that with an increasing step of welding chamber, more uniform velocity and temperature distributions in the cross-section of the extrudate were observed. In addition, the weld quality was improved owing to increasing welding pressure, when adopting the multi-step welding chamber.


2011 ◽  
Vol 491 ◽  
pp. 105-112 ◽  
Author(s):  
Yawar Abbas Khan ◽  
Henry Sigvart Valberg

Hollow and semi-hollow profiles are commonly produced by extrusion using porthole dies. The main characteristics of such dies are the presence of a mandrel (core) to shape the inner contour of hollow profile and bridges or legs to carry the mandrel. The bridges split the billet material into multiple metal streams that flow through the porthole channels and meet in the welding chamber behind the bridge where they are joined by pressure welding. When hollow profiles with different wall thickness are made the size of two adjacent portholes may be different. The material then flows through the two portholes with different flow velocity so that there is more feed through the bigger porthole into the weld chamber behind the bridge. Experiments have been performed and are reported here in which a grid pattern technique was used to characterize the metal flow through a 2D-die with porthole channels of unequal size. The design of the laboratory die has been modified in relation to the symmetric case to get different sizes of the two portholes. Since the metal flow through such a die is asymmetric the grid pattern technique was also modified to characterize the experimental flow. The results of an experimental metal flow study performed for a short billet was presented in a previous article [1]. Corresponding experiments performed with longer billets are now reported; so that two stages of the extrusion process is analysed here. The grid pattern technique has successfully mapped the non-symmetric material flow as in industrial extrusion when using different wall thickness over the section. The lateral movement of metal during extrusion is obtained from one set of experiments; the vertical movement from the other set. Finite element analysis of the extrusion process has been performed using Deform 3D. The encountering of the two metal streams behind the die bridge and the deformation characteristics within the welding chamber has been studied this way. Extrusion weld formation and deformations around the die bridge are considered here with the help of experimental results and simulation models. The nature of the metal flow achieved from the FE-model is compared with the experimental results. As regards the short billet some results are presented in [1], however improvement to the previous model gives a more perfect match. The model also provides information about the boundary conditions in real extrusion.


2011 ◽  
Vol 491 ◽  
pp. 241-247 ◽  
Author(s):  
Pouria Homayoun ◽  
Mostafa Ketabchi

Extrusion is a deformation process used in metal sections fabrication. Metal flow pattern during extrusion process is of great importance. How circular initial section of billet changes to final section provides more details of extrusion process, and plays an important role in optimizing the extrusion energy. Extrusion in flat-faced die, without intermediate section, needs much more energy than is required for die having intermediate section. The aim of this study was to investigate the effect of strain rate on metal flow pattern in T-section extrusion process. Four different ram speeds were applied to realize how the shape and position of intermediate section would be affected. Flat-faced die with “T” final section was designed and manufactured. Straight layout of metal was of top concern in die design. Commercial purity aluminum, Al 99.5, was extruded in flat-faced die in hot condition. Graphite was used as lubricant in deformation process. After partial extrusion of billets, the residual part of billets pounced out of container and then mounted for metallographic tests. This part of billets consisted of dead-metal zone and deformation zone. Then, step-by-step decreasing of specimen height followed by macro-etching of metal surface paved the way for determining the metal flow pattern. An egg-shaped intermediate section appeared between initial round section and final “T” section. The size and position of the intermediate section changed by varying the strain rate of extrusion process; It was also revealed that as the strain rate of extrusion process is increased, the dead-metal zones become narrower and the dead-metal zone semi angle increases.


2009 ◽  
Vol 424 ◽  
pp. 145-152 ◽  
Author(s):  
Henry Sigvart Valberg

The mechanics of metal flow through long choked die channels have been investigated in unlubricated hot aluminum extrusion. Experiments were performed in a laboratory press at an earlier occasion by letting a grid pattern introduced into the billet flow down into the choked die channel to appear adjacent to the channel wall. The grid pattern was then revealed to characterize the metal flow in the channel. A 2D-model of the extrusion process was made. The model was applied to study the conditions in the extrusion experiments and in this model good similarity was obtained with the experiment. New knowledge regarding the metal flow through a choked die channel have been obtained this way, such as; contact conditions, presence of sticking and sliding zones, friction conditions in the sliding contact zone and the velocity profile over the cross-section of the channel.


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