showed that in flashless forging of connecting rods one could use preforms obtained via powder metallurgy. investigated the formation of Al-Si alloy tie-rod ends for the steering systems for automobiles, finding that preforms could be produced by casting. The best results were obtained using friction-welded preforms. investigated whether preforms welded by different methods, made of either the same or two different materials, could be used in the forging process. The other group of research works relates to the development of new methods for preform production. The first one concerns the use of new methods for preform shape design, such as evolutionary structural optimization, electric field theory and genetic algorithms. These studies can be divided into two groups. Shanghai Jiao Tong University, Korea Advanced Institute of Science and Technology, Institut für Integrierte Produktion Hannover, and University of Ulsan) are conducting studies on preforms. optimized preform shape in the forging process of an airfoil blade, which made it possible to reduce flash volume (by 51%) and strain non-uniformity (by 42%). , who focussed on preventing defects in a half axle flange. Another objective function for preform optimization was employed by Sun et al. used the same computer programme to optimize preform shape and thus minimize differences in strain distribution. For example, Vasquez and Altan proposed a preform design method based on numerical simulations using DEFORM-3D, in which a connecting rod was produced by flashless forging. Both numerical modelling and the use of optimization techniques play an important role in the design of forging processes. The proper design of preform shape is necessary to implement the more and more popular precision forging method that allows significant reduction in material consumption. Tadeusz Rut’s method ), longitudinal rolling, and cross rolling. Numerous methods for forming preforms are used in industrial practice, including open-die forging, rotary swaging, electrical upsetting, machine forging, forging with the use of special devices (e.g. Individual cross-sections of a preform are equal to respective cross-sections of a forging increased by flash allowance. A preform is an axisymmetric solid with its shape being as close as possible to that of a forging, especially in terms of its profile in the parting plane. Experimental results demonstrated that the rolled parts had no internal defects (cracks) and were characterized by high dimensional accuracy.ĭie forging processes for elongated forged parts of complex shapes are performed using billet material in the form of preforms. Following the numerical analysis, experiments were performed in which the preforms were rolled under laboratory conditions (in a scale of 1:2). Numerical simulations of the forging process showed that all forged parts had the required shape, which indicates that the preforms were designed correctly. It was found that the forming process of preforms performed in a CNC skew rolling mill was characterized by relatively low force parameters in relation to the dimensions of formed parts. Loads and torques in the rolling process were measured. Distributions of temperature, effective strain and damage function were determined for rolled preforms. The shapes and dimensions of preforms were designed, and rolling and closed-died forging processes for producing these parts were simulated numerically. First, a numerical analysis was performed to investigate forming processes for three different parts: a scraper, a connecting rod, and a hook. Notes: The current error page you are seeing can be replaced by a custom error page by modifying the "defaultRedirect" attribute of the application's configuration tag to point to a custom error page URL.This paper relates to a study on the formation of elongated preforms in a CNC skew rolling mill. This tag should then have its "mode" attribute set to "Off". It could, however, be viewed by browsers running on the local server machine.ĭetails: To enable the details of this specific error message to be viewable on remote machines, please create a tag within a "web.config" configuration file located in the root directory of the current web application. The current custom error settings for this application prevent the details of the application error from being viewed remotely (for security reasons). Runtime Error Description: An application error occurred on the server. Runtime Error Server Error in '/' Application.
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