Papers by Keyword: Tooling

Abstract: This paper explores the possibility of using different 3d printing methods and materials in the production of polymer molds for injection molding applications. A mold producing a cube was designed using a commercial software. Following the standard 3d printing process, injection molds which could produce a cube were printed using different 3d printing materials and 3d printing technologies. The 3d printing technologies used were Stereolithography (SLA), Polyjet and Fused Filament Fabrication (FFF). A bench-top injection molding machine was used to inject polylactic acid (PLA) in these molds. The quality of the injected parts in terms of dimensional accuracy has been investigated. In some cases, the damage mechanism of the polymer molds has also been observed.

Abstract: In the article the results of the finite element modeling of cold extrusion of carbon steel, the stress-strain state of massive dies at high cyclic stresses characteristic of the cold extrusion of steel are presented. The possibility of significant amplification of dies in their working area by creating a variable external pressure from the rims of a special design is shown. Dies banding with variable external pressure, proportional to the internal pressure in the die, is aimed at increasing the technical resource of the tool.

Abstract: Nowadays, globalisation enables a rapid uptake of the classical manufacturing technologies. In order to remain competitive and fulfil the global trend of reduction of emissions, innovative production processes that reduce the energy and raw material consumption should arise. Semisolid forging (SSF) is one of those techniques with great potential to fulfil those requirements maintaining the high quality of the components. Thus, the objective of this work is twofold: to produce a complex geometry part saving material and energy using the off-the-shelf S48C steel grade, and to demonstrate the capability of the process to produce a pre-series of 250 components without excessive tooling damage.

Abstract: In multiple stages forging, an appropriate pre-form has reduced production cost, loss of material, and forging load, and it has also improved die life. However, it is difficult for beginner to make the process design of the pre-form because they have poor technical information. For example, experts have experimental knowledge how to form an oval cylinder by upsetting of a right cylinder with a mild-wedged die. This oval upsetting needs no container with oval hole. This paper investigates the oval upsetting with the relationship between the nose angle of the mild-wedged die and the shape of the product for assistance of the process design in forging. As the results, when the mild-wedged die having an appropriate angle and nose radius was applied to the upsetting, the oval cross-sectional ratio of the major axis to the minor axis achieved 1.45.

Abstract: According to the characteristics of exhaust pipe, a radial crushing system was designed in this paper, and the focus was laid on the design and analysis of the bulging tooling and hydraulic system. Moreover, overflow pressure was calculated in detailed, and the joint strength between mandrel and hydraulic pipe was checked. The results show that the radial crushing system has the advantages of simple structure, rational design, reliable work and adaptable.

Abstract: In this paper a new variable forming tool concept and associated numerical methods for calculating optimal actuator layout and estimating CFRP part quality are presented. The concept of the tool features a modular design and active control of the forming process to achieve the desired geometry. Initially the laminate is placed on the flat top layer of the forming tool. There it is fixed and compacted using vacuum bagging. After compacting, it is heated up to increase the performance of the forming process using water based tempering of the forming tools top layer. The heated laminate is then formed, pulling the tools top layer into the desired geometry using the actuators. Finally, the formed laminate is cooled and transferred into a mold for curing. The position of the forming tools actuators on the base plates is variable. Numerical optimization in combination with finite element (FE) technologies is utilized, to approximate the tool surface within given error margins, with as few actuators as possible. In addition, results of a numerical method for part quality estimation are shown. The influence of the forming process on mechanical properties due to fiber waviness is taking into account using a self-developed method that includes manufacturing characteristics in FE modeling of the part. The method is based on mathematical descriptions of fiber waviness, which are implemented into a FE model. Therefore a structure discretization assuming perfect fiber orientations is realized and the expected fiber waviness induced by the forming process is applied element-wise.

Abstract: The automotive sector is one of the largest energy consumers in Germany. Requests from politics and industry to significantly reduce emissions require new developments during utilization as well as during production phase. In line with the framework concept "InnoCaT", where more than 60 companies and research facilities from Germany take part, possibilities for producing companies are developed and analyzed to reduce the resource and energy consumption and by this reducing costs along the entire process chain of car body manufacturing. One approach to design car bodies lighter and more efficiently is to use aluminium and high strength steels. By this means weight and sheet thickness are reduced. However higher strengths of the steels and the adhesion affinity of aluminium significantly increase the requirements regarding the used tool steel. Thus grooves or galling appear more frequent at highly stressed surfaces. To assure high lifetimes and by this increase especially the resource efficiency concerning use of material and setting-up times within the press plant, a local optimization at the highly stressed surfaces is necessary. For this a FEM/BEM-tool for a time efficient and exact calculation of the occurring tool loads for complex die profiles is developed. Based on this development of load calculation a shape-optimization is performed at the corresponding areas. After the geometric optimization of the tool a local laser surface treatment for further wear protection is carried out using laser cladding or laser alloying/ -dispersing. By combining the technologies a highly wear resistant surface is achievable, which increases the tool's lifetime as well as the reproducibility within production.

Abstract: If the gap between the curved plate and throw cut tobacco roller of the throwing tobacco agency in PROTOS cigarette machine is improperly adjusted, easily lead to the curved plate wear faster, tobacco-made pieces increases, short cigarettes increased. However, there is no a adjust tooling for the curved plate. To solve this problem, a new type of curved plate adjust tooling is designed. The three movable reference wheels used to test and adjust the gap instead of the reference plane. The application results show that the new tooling is an effective solution to solve the installation and adjustment problems of the curved plate. The installation and adjustment of working hours decreased from 2.5 hours to 1.5 hours. It also ensures the curved plate mounting quality and precision requirements and reduces tobacco-made pieces rate and cigarettes short rate.

Abstract: It is difficult to disassembly and time-consuming when the turnover drum need to repair or maintenance due to the turnover drum is a complex structure and high precision parts in PROTOS cigarette machine and the original special tooling has some limitations. To solve this problem, a new type of turnover drum tooling is designed. The application results show that the new tooling is an effective solution to solve the turnover drum maintenance difficulties, disassembly time-consuming problem. The maintenance lead time reduce from 12 hours to 4 hours. It also ensures accuracy of parts after the dismantling of the turnover drum and eliminates the security risks that exist in the repair process.

Abstract: A simple and practical hydraulic deep drawing test tooling is developed to investigate metal sheets formability. It is composed of two parts including the forming die and hydraulic control system. Experiments with varied material and dimensional sheets of hydraulic deep drawing and mechanical deep drawing can be fulfilled by the tooling on a Single-Action Press without complicate external hydraulic system, blank holder system and oriented system for punch, respectively. The tooling is testified to be simply, facile and reliable, which can perfectly perform the sheets forming in hydraulic deep drawing, and the formability of sheets was improved effectively with hydraulic deep drawing.