TOOLING DESIGN IMPROVEMENT OF MULTISTAGE COLD FORGING OF SPECIALTY SHAPED NUTS USING CAE AND 3D PRINTING

Given its critical role in the fastener industry, cold forging is widely performed in automotive production, manufacturing, aviation, and 3C products. Personnel experience and trying error approaches provide a subjective and unreliable background despite their extensive use in fastener forming and die design owing to the difficulty in controlling the development schedule. This study used DEFORM-3D analysis software to investigate the die service life from producing specialty shaped nuts in a multistage cold forging process. Effective stress, effective strain, velocity field, and other quantitative metrics of dies and work-pieces can be obtained from numerical simulations. Herein, 3D printing technology is also implemented to create cold forging dies and deformed work-pieces for assessing the dimension of tooling assembly. This process allows engineers to gain a better understanding of the tooling design at development phase and derives the parts, which were previously just simulation results from DEFORM-3D forming software. Results can help a multistage processing factory establish a cold forming capacity for the development of new products. Consequently, the ability of self-design and self-manufacture of specialty shaped fasteners in Taiwan could be increased widely to enhance the international competitiveness of domestic industries.

Optimize Design on the Key Parts of Ring Die Fuel Pellet Machine

This paper analyzes the problems existing in the design and operation of ring die fuel pellet machine, and proposed to optimize the key parts. Determine the reasonable number of roller on the theory of fatigue damage after drawing up the related design parameters of ring die and the roller, a three-dimensional model of the link mold pellet machine is established using Pro/E soft-ware, and transferred the model into ADAMS software through Mech/Pro which dedicated interface software, then used ADAMS to make a dynamics simulation. Through calculation, the stress amplitude impact on the ring die and the Energy consumption per unit output are smallest when roller number is four. So, ring die service life and equipment production efficiency can be improved effectively through setting up reasonable roller number. Keywords-fuel pellet machine; roller; ring die; fatigue damage; three-dimensional model; dynamics simulation

Die-Casting Die Design Based on the Application of CAE Simulation

High pressure die casting is a high volume component manufacturing process which is used extensively in many aspects. There are many factors affecting the quality of die-casting die. In this paper, the CAE simulations of filling and solidification processes for die-casting are studied. Numerical analyses are presented for two practical die-casting parts using HZ CAE software. The temperature distributions and filling states in solidification and filling process are presented. Then the deficiencies of the part are predicted. Based on the analyzing results, the structures of the two dies are optimized and longer die service life and high-quality castings are obtained. It is proved that CAE simulation results can offer a helpful reference for die-casting die design.

Prediction of damage zone in hot forging die and suggesting proper heat treatment for improving die service life

In the present research, using MSC Super Forge simulation software and analysis of stress, strain, contact pressure, and temperature distribution in different points of hot forging operation of a work piece and also by considering the interaction between the work piece and die, the zones of die which are prone to early failure and damage have been predicted. The results of simulation have been compared with experimental results of die service. Simulation outputs show a good agreement with practical conditions. In the next step, after studying the effect of heat treatment on the die performance, a proper heat treatment procedure is introduced to improve die service life. Finally, capability of this solution to overcome die damages would be verified with practical behavior of dies.

Study on the Rules and Effects of Wear on Die Service Life in Steel Synchronizer Gear Ring Forging Process

The die accuracy and die service life reduce due to die wear during precision forming processes of steel synchronizer gear ring. The most serious part of wear is the middle between two tooth shapes. The rules of the wear and initial die hardness and frictional coefficient are analyzed based on numerical simulation. It shows that the higher of the initial die hardness, the better antiwear and good lubrication is benefit to reduce wear and prolong the die service life. The effect of the temperature on die life is reflected through hardness. The relationship of die hardness and die temperature, forming time is deduced. The higher of the die temperature and the longer of the forging time, the more serious of die wear. To prolong the die life and improve the quality of forgings, the synthetic forming technology is adopted and the ejection way and control system of the Plate Friction Press are improved. Experiment verification shows that the die service life has been prolonged.

Influence of Billet Quality on Hot Extrusion Die Life and its Relationship with Process Parameters

Apart from other factors such as die design and manufacturing, heat treatment, working conditions etc, performance of hot extrusion die can directly be related to the billet quality used in the extrusion press. The purpose of this paper is to investigate the effect of Al-6063 billet source (primary or secondary) on extrusion die life based on microstructural and statistical analyses. In microstructural investigation, secondary (remelt) billet cast in-house at local extrusion plant is compared with primary (smelter) billet by applying different material characterization techniques including optical microscopy, hardness measurement, X-ray diffraction (XRD) analysis, and energy dispersive spectroscopy (EDS). The statistical study is based on the failure history of some 53 hollow-profile dies in which the effect of billet quality on various measurable process parameters including extrusion ratio, billet temperature, exit temperature and repeated nitriding is analysed and related with useful die service life. Comparatively coarse grain structure, non-homogeneous distribution of secondary phases, and high hardness in the case of secondary billet were found responsible for poor die performance as observed in statistical investigation of failed dies. Two types of regression models are also proposed for prediction of die life in terms of secondary billets’ usage and measurable influencing parameters. Using current results, some suggestions during in-house billet preparation of secondary billets have been devised for improved die life.

Performance of Al-6063 Primary and Secondary Billets Used in Hot Aluminum Extrusion

The service life of tooling plays an important part in the economics of the extrusion process. A number of causes are considered responsible for initiating damage to the dies before its designated life is reached. Apart from other factors such as die design and manufacturing, heat treatment, working conditions, etc, the performance of the die can directly be related to the billet quality used in the extrusion press. The purpose of this paper is to investigate the effect of Al-6063 billet source (primary or secondary) on extrusion die failure, based on microstructural investigation. A secondary (remelt) billet cast in-house at a local extrusion plant is compared with a primary (smelter) billet by applying different material characterization techniques, including optical microscopy, Vickers microhardness measurement, X-ray diffraction (XRD) analysis, and energy dispersive spectroscopy (EDS). It is observed that a secondary billet has a comparatively coarse grain structure, nonhomogeneous distribution of secondary phases, inclusions, and high hardness that can be associated with poor casting and homogenization practice. In view of present results, some suggestions during in-house billet preparation of secondary billets have been formulated for improved die service life.