Simulation of a full forward extrusion process from metal strip marion merklein, tommaso stellin and ulf engel chair of manufacturing technology, university of erlangennuremberg, d91058 erlangen, germany abstract. By using this method it is possible to obtain data concerning the pressure distribution along the punch face. Combined extrusionforging is used in the manufacturing of a wide range of engineering components. Metal can also be forced to flow into recesses in the punch, see fig. Sometime you will fine that adobes photoshop help is quite useful. In forward extrusion, the diameter of a rod or tube is reduced by forcing it through. Forward extrusion is used to produce bolts, screws or stepped shafts. The friction in rod forward and backward micro extrusion. When you use this software, please refer to the usage and examples. The interest on mass production of small complex metal components is currently fostered by fields like electronics and micromechanics. May 16, 2016 10 most amazing epoxy resin and wood river table designs. The default toolbar contains frequently used tools. Applicability of a modified backward extrusion process on. Socket wrench is a hollow cy linder, which is used to insert or remove the bolt or nut heads.
Figure 2 illus trates the process and shows the deforming body divided into. The process can be carried out hot or cold depending on the. In metal forming industries, many products have to be formed in large numbers and with highly accurate dimensions. Forward and backward extrusion types of extrusion youtube. Forward ram and billet move in the same direction and. Three dimensional analysis of combined forward and backward. Two smaller shoulders are formed and stem is forward extruded. To save energy and material it is necessary to understand the behavior of material and to know the intermediate shapes of the formed parts and the mutual. The deformation region is divided into five zones separated by planer and cylindrical surfaces of velocity discontinuities. Several microextrusion processes have been developed since microforming was envisioned in 1990. Introduction the backward extrusion is a widely used cold forming process for the manufacturing of hollow shape symmetric, cylindrical products and it is usually performed on a highspeed and accurate mechanical presses. It presents the forward, backward and active friction force extrusion. Extrusion process and its types by basic engineering duration.
Depending on the direction of metal flow, extrusion processes can be either forward also called direct, backward also called indirect or lateral. The finite element results are compared with experimental data in. Help on photoshop shortcuts keys is very good to the point it even let you know that you should not count on the f keys shortcut to as adobe sets the for assign the f keys to an action it will override adobe default settings. Materials of workpieces were mild steel and aluminum.
The upper bound approach is used to analyze combined backwardforward extrusion. Based on obtained results, in the novel backward extrusion process the required force to produce a particular product can be reduced by up to 20% in comparison with conventional backward extrusion. Figure 2a, and secondly the middle boss and pole claws, as shown in 2c, were. Figure formed by backward extrusion on the thicker.
I summarized required formula but if you need more info ask or check the book. In backward impact extrusion, the metal flows in the opposite direction that the force is delivered. The present paper deals with the finite element analysis of combined forward and backward extrusion forging process for the product shape socket wrench. Extruder classification extruders may be classified by three figures, for example, 16024. Several geometrical parameters are influenced the flowing of the material such as. To save energy and material it is necessary to understand the behavior of material and to know the intermediate shapes of the formed parts and the mutual effects between tool. Like upsetting, extrusion simply rearranges the shape of the blank and there is no loss of material. A schematic of these processes is shown in figure 1. Comparison of rod forward and backward extrusion loading curves with constant friction shear factor m0,12 next two simulation processes for forward and backward extrusion have been conducted using a tool with surface characterized by the triangular wave. It is very costly to conduct different trail runs to know the metal flow patterns, and for.
Clipping is a handy way to collect important slides you want to go back to later. Station 6forward extrusion taper is formed above large shoulder. Forward extrusion is the most common of these three methods 6. Extrusion the first chapter of this book discusses the fundamentals of extrusion technology, including extrusion principles, processes, mechanics, and variables and their effects on extrusion. Backward cold extrusion of cylindrical billet by the punch with square cross section was, program package simufactforming v10. Comparison of rod forward and backward extrusion loading curves with constant friction shear factor m0,12. Two different lubricants were used in order to determine. To observe the microstructure, the samples were sprayed with 5% nital. Pdf in this article the forwardbackwardradial extrusion processes analyzed. Microextrusion is an outgrowth of microforming, a science that was in its infancy in the early 1990s. Accordingly, to deal with this issue, whenever possible one can use indirect or backward extrusion, wherein comparative lesser force is required for extruding the material.
Sep 22, 2017 impact, hydrostatic and tube extrusion. Pdf analysis of forwardbackwardradial extrusion process. The equipment that does this is called the post extrusion equipment, while the whole system is called an extrusion line. Process simulation for the backward extrusion of internally arbitraryshaped tubes from circular billets is presented in this article. Metal is forced to flow in the direction opposite to the punch movement. Feb 26, 2017 sometime you will fine that adobes photoshop help is quite useful. Microextrusion is a microforming extrusion process performed at the submillimeter range. Extrusion has been around as early as the 1800s known at that time as squirting. The forwardbackward algorithm is an inference algorithm for hidden markov models which computes the posterior marginals of all hidden state variables given a sequence of observationsemissions,, i. How to survive alone in the wilderness for 1 week eastern woodlands duration. The solution predicts the required relative ram pressure as a function of the process geometry. In forward backwardradial extrusion process the forward cup is smaller than the backward cup, but an increase in friction factor decreases this difference.
Ufg al 1070, produced by twoturn, schannel ecap, was side upset and rolled to obtain a 1 mm thick sheet. This method produces shorter lengths than the forward extrusion process. Forward extrusion article about forward extrusion by the. You can find formulas for backward extrusion in groovers principles of modern manufacturing 4th edition section 17. For example, if the simultaneous forward and backward extrusions do not go well in the third stage, the forward extrusion can be left in the third stage, and the backward extrusion can be done in the fourth stage. The internal power of deformation and shear and friction losses are computed individually and summed. Introduction the process of backward extrusion still plays an. Station 5backward extrusion center hole is formed through backward extrusion. It also deals with the possibility of increasing the accuracy of the method. Simulation of a full forward extrusion process from metal. Investigation of process parameters for the backward.
Fem simulation of friction testing method based on combined. This kind of analysis has been done before using analytical methods such as the upper bound theorem. The paper analyses the process of simulation forward backward extrusion. Results of investigation forward and backward extrusion with fem. Both hollow forward impact extrusion and hollow backward impact extrusion have, in principle, the same process steps with the exception that in hollow. Analysis of forwardbackwardradial extrusion process analysis of forwardbackwardradial extrusion process farhoumand, a ebrahimi, r. The forward backwardradial extrusion process can be used to produce components that feature a hoop protrusion like gears and flanges that come with hollow shafts. How can i fix a pdf document that was scanned backwards. On the other hand the study in the combined forward backward extrusion process is still less than other extrusion processes to predict the metal flow presentation and load requirements as a. Current paper elaborates numerical and experimental analysis of backward extrusion by the punches with square cross sections. Three dimensional analysis of combined forward and. Due to the complexity of the forming process and because of so many process variables, it is difficult to predict the forming load required to manufacture a given component. Based on the structure analysis, a new forming process was put forward. Fem simulation of friction testing method based on.
Forward and backward extrusionforward and backward extrusion tapany udomphol 9. Backward extrusion is shown in figure 228, forward and combination impact extrusions are illustrated as follows. In the first stage, axisymmetric forward extrusion and nonaxisymmetric backward extrusion simultaneously take place until the backward extrusion of a wrench socket is completed. In combination, the metal flows in both directions. The upperbound analysis for the combined forwardbackward extrusion was provided by avitzur, b. Experimental and numerical simulation of the bac kward extrusion process for annealed steel aisi 1010 17 analyzed without attack on an optical microscope, leitz brand, an increase of 200x and scanning electron microscope, jeol brand and voltage 20kv. A ubet analysis of nonaxisymmetric forward and backward. The two nonlubricated hot extrusion methods are forward or direct extrusion and backward or. Jun 01, 2009 this paper presents the analysis of forwardbackwardradial extrusion process. The backward extrusion loading curve suggests lack of friction impact in the vicinity of the container. Some methods of combined extrusion are double backward extrusion 1, backward forward extrusion 2345, radial backward extrusion 6, 7, radial forward extrusion 8910and forward. The theoretical calibration curves are obtained by rigidplastic fem simulations in a combined forward rodbackward can extrusion process for a reduction in area r b, 25, 50 and 70 percent in the backward can extrusion.
Many people use the buttons on the page navigation toolbar, but you can also use arrow keys, scroll bars, and other features to move forward and backward through a multipage pdf the page navigation toolbar opens by default. In forwardbackwardradial extrusion process the upper punch moves downward while the lower punch is stationary. Metal flow control in cold simultaneous fowvardbackward extrusion. The upperbound analysis for the combined forward backward extrusion was provided by avitzur, b. A ubet analysis of nonaxisymmetric forward and backward extrusion a ubet analysis of nonaxisymmetric forward and backward extrusion lee, h. The forward impact extrusion process is most widely used. This article discusses nonlubricated and lubricated hot extrusion. Backward extrusion using microblanked aluminium sheet. Schematic representation of backward extrusion of hollow shapes where.
Publishers pdf, also known as version of record includes final. On the other hand the study in the combined forwardbackward extrusion process is still less than other extrusion processes to predict the metal flow presentation and load requirements as a. Forward extrusion with diametrically opposed thread engagement increased core diameter approaching the underside of the head causes additional forward and backward extrusion providing increased thread engagement the solution for thin sheet metal applications over the last several years, industry has improved assembly processes and reduced the. The upper bound approach is used to analyze combined backward forward extrusion. Abaqus software is used for finite element simulations. For the ubet analysis, the extrusion process is assumed to have two stages. Figure 2b, was formed by radial forging on ring billet, as shown in. Analysis of combined backwardforward extrusion journal of. In the previous blog on direct extrusion, we had pointed the main disadvantage of direct extrusion being the excess use of force due to friction between the cylinder and billet. Backward can extrusion and materials behaviour technische. Pdf in the metal forming process, one of the prominent techniques is combined forward backward extrusion route. Abaqusexplicit finite element method has been used to analyze the problem.
The basic processes solid forwards, solid backwards, hollow forwards and hollow backwards all belong to the impact extrusion process with quasistationary material flow, which means that on the whole, deformation is distributed homogeneously across the crosssection of the workpiece, a few locally limited exceptions being possible. Pdf combined forward backward extrusion of socket adapter. Pdf three dimensional analysis of combined forward and. Effects and applications of geometry variations on the. Bharat industries blog indirect or backward extrusion. The type of extrusion we are studying is direct extrusion, also known as forward extrusion, and is the most popular of the three forms of extrusion. The theoretical calibration curves are obtained by rigidplastic fem simulations in a combined forward rod backward can extrusion process for a reduction in area r b, 25, 50 and 70 percent in the backward can extrusion. A square hollow tube can be produced by a forward extrusion b. However, the fem solution presented here is the first of its.
Both hollow forward impact extrusion and hollow backward impact extrusion have, in principle, the same process steps with. Analysis of forwardbackwardradial extrusion process. After calibration the billets were used for backward extrusion of microcups. Station 42nd blow extrusion shoulder is squared, and centering marks formed in ends to assist in subsequent operations. Forward extrusion, where metal is forced to flow in the same direction as the ram being used to apply pressure. A concern within the industry is the continuing edu. Some methods of combined extrusion are double backward extrusion 1, backward forward extrusion 2345, radial backward extrusion 6, 7, radial forward extrusion 8910 and forward. This problem can be addressed by surrounding the billet with fluid inside the container and. In order to display the merits of the cold combined forwardbackward extrusion process.
A feature based upper bound model to analyze the backward tube extrusion proposed by malpani and kumar 16. The paper analyses the process of simulation forwardbackward extrusion. Jun 15, 2001 in this study, ubet is used to analyze the forward and backward extrusion of hexagonal and trochoidalshaped wrench bolts. Based on obtained results, in the novel backward extrusion process the required force to produce a particular product can be reduced by up to 20% in comparison with. Three dimensional analysis of combined extrusionforging process. Numerical simulation of combined forwardbackward extrusion.