In flashless precision forging the punch moves in the cavity after die closing. Thus, the material is distributed until complete form filling. Using a new developed forging tool, parts can be pierced within the forging operation. In this tool concept the punch goes through the entire thickness of the part. By the upper punch the excess material is pressed as far down as the workpiece is completely pierced. To test this tool concept on its practicality, forging experiments were carried out on a screw press.
forging, flashless, precision, piercing
The early detection of defects in forged parts offers economical advantages due to the possibility of sorting them out of the process chain. The aim of the presented research project is the development of a forging process monitoring without sensors. In the process electric current is flowing through the forged part. The quality of the forged parts is measured by the electrical signal. Typical defects of forgings like underfilling and wrong temperature of the billet show characteristic signals and therefore can be detected. These parts are sorted out of the process chain. The user of the forging machine is able to adjust the forging process immediately.
forging, process monitoring
The implementation of process monitoring technologies in manufacturing processes allows significant cost and time savings. An online process monitoring of die cavity filling in warm forging processes could not be realized until now. Important process parameters for example billet volume, billet temperature or lubrication could only be observed after forging. This paper describes the implementation of an online process monitoring system based on electricity.
forging, process monitoring
To produce preforms for complex long flat parts with an unsteady mass distribution along the longitudinal axis rolling processes, like cross wedge rolling, can be used. Tools for cross wedge rolling processes can be constructed as roller or flat, both with wedges. In the collaborative research project "SFB 489 - Process chain for the production of precision forged high performance parts" the subproject "Innovative machine and tool technology for precision forging" deals with the development of a flashless forging process for a two cylinder crankshaft with pin and flange. This process is developed by IPH - Institut für Integrierte Produktion Hannover. The first preform of the developed forging sequence is produced by a cross wedge rolling process on the basis of flat with wedges. To consider the mass distribution of the two cylinder crankshaft in the preform for a rolling process four mass concentrations for the crank arms and mass concentrations for pin and flange are needed.
crankshaft, cross wedge rolling (CWR), forging sequence, preform, rolling process
Lightweight design of cars is one way to reduce fuel consumption and increase the range of cars. This is an important factor to attain the EU limit values for CO2 emissions for vehicles and thus to avoid penalties for exceeding these limits as of the year 2012. The growing number of uses for high-strength steels or lightweight structures are adequate means to reduce weight. At IPH - Institut für Integrierte Produktion Hannover gGmbH a method to produce hollow profiles made of aluminum was developed. This method, called hydroforging, combines flashless forging and tube hydroforming. It allows the production of thick-walled hollow aluminum profiles with undercuts without the need for complex tool kinematics. The forging is supported by an active medium. A tool concept has been developed using the drives of a hydraulic press with die cushion. With this tool, various part geometries shall be produced and analyzed. To produce the tools' interior pressure and the forming pressure, liquid tin as an incompressible active medium is used. The forming is initiated by upsetting the aluminum profiles and supported by the active medium, so that the profile is pushed against the cavity of the dies. The process was designed based on simulations and will be verified by practical experiments. This paper describes the development of the forging process with an active medium.
hydroforming, forging, tubes, aluminium, FEA
This paper discusses the influence of circadian performance fluctuations on workers conducting manual assembly tasks under consideration of biorhythm. A data analysis method statistically verifies the correlations between performance fluctuations and investigated biorhythm. Finally, the paper suggests different areas of practical application of the confirmed performance fluctuations (e.g. shift work, cycle time adjustment).
performance efficiency fluctuation, assembly, industrial work system, data analysis method
This paper discusses the different characteristics used to describe XXL-Products and, furthermore represents fundamental aspects concerning the construction (eg. principles, methods) of production systems. A survey of experts at XXL-Producers is used to identify the most commonly used production systems. The article demonstrates the survey results and finally concludes with an outlook on further actions.
lean-production-methods, production system, xxl-products
In order to obtain high logistical performance in a production network at low logistical costs, there has to be a high level of synchronization in the material provision of the final assembly. The level of synchronization can be restrained by dynamic effects in a network. This paper presents an approach for identifying critical material procurement processes that are accountable for an insufficient achievement of logistical goals in the material provision. In addition, the results of a simulation study are explained that analyzes the effects of measurements conducted to increase the synchronization of the material provision by also taking dynamic effects into account.
dynamics, material provision, production networks, production planning and control (ppc)
Many small and medium enterprises (SMEs) miss their logistics objectives. In science and practice there is a growing recognition that the problems of production planning and control (PPC) cannot be solved only by the development and use of software tools. PPC systems usually have limited degrees of freedom for carrying out the tasks given to the employee. Many methods of PPC systems have the potential of influencing the behavior and performance of employees. The development of a logistics-oriented incentive system can support the logistical goal achievement of SME. Aligning incentives on operational logistics objectives anchors the objectives in the employees’ personal consciousness and everyday commitment the employees’ actions to support the logistics performance on the production level.
controlling, logsitic performance indicators, incentive system,
The lecture introduced IPH – Institut für Integrierte Produktion Hannover gGmbH with its three fields of activity: forming technology, logistics and automation technology. Furthermore, research and consulting projects were discussed. In addition, the challenges regarding 8D report-based complaint management were presented as a major focus of current research.
quality management, complaint management, 8d report, data mining, text mining
The lecture introduced IPH – Institut für Integrierte Produktion Hannover gGmbH with its three fields of activity: forming technology, logistics and automation technology. Furthermore, research and consulting projects were discussed. In addition, the challenges regarding the implementation of lean production were presented as a major focus of current research.
production system, lean production, expert system, knowledge management, data mining
To meet the growing demand for energy, further developments are necessary in the field of renewable energies. In two research projects, engineers of IPH - Institut für Integrierte Produktion Hannover have investigated how to increase the efficiency of wind turbines.
xxl products, large-scale products, wind turbines, data mining
The performance in logistics is vitally important for Companies. However the achievement of logistics objectives is deflating in practice. A possible reason are divergent employee and company interests, which constrict an efficient order processing. Once more employees are in focus in research and practice. How to resolve these differences in employee and company interests to enhance logistics? The Incentive System which is developed by IFA and IPH in Hannover provides solutions for an effective support of logistic objectives.
incentive system, logistics, divergent employee and company interests
Warm forged parts have advantages in comparison to conventional hot forged parts: Closer tolerance, reduced surface roughness, no scale and reduced decarburization. However, the geometrical spectrum of warm forged parts is restricted by high flow stress. To overcome this geometrical limitation, new rolling and forging processes have been developed in the Seventh framework programme EU in research project “DeVaPro – Development of a Variable Warm Forging Process Chain”. In the focus is layout of warm preforming operation by cross wedge rolling followed by an intermediate heating and warm final forming in conventional dies. In this paper results of initial experimental tests and results of application of warm cross wedge rolling are shown.
shrinkage compensation, fem
The aim is the development of a function-based method to support the planning of offerings in injection molding. It is assumed that tools and shapes are unique items, but the tools’ functions are recurrent. Possible post-calculations are captured and can be used better for the calculation of offerings via the function-based calculation. Methods of similarity search assist in prediction and precise determination of manufacturing expense of a tool. In order of the validation of the concept by real data the software-demonstrator is linked to existent post-calculation tools and transferred conceptually to further unique products.
function-based method, tender preparation, injection molding
Thin diamond cutting discs help to increase efficiency in the production of slabs and tiles out of natural stone. The reduced stiffness of the discs, however, may lead to higher tool deflection and reduced cutting quality. This can be compensated by using higher cutting speeds. So far, such an intervention needs to be supervised by an operator. For ergonomic and economic reasons this is not an option for the industry. Up to now, no system able to monitor the tool vibrations near the source during the cutting process exists. On this account, such a system has been developed. Due to the integration of piezoelectric elements in the grinding tool, the vibrations can be measured right at the source. This ensures the high accuracy of the measuring process. The measured data will be transmitted wirelessly to a computer evaluating the results. Cutting tests show that the sensor integrated tool is able to monitor the tool vibration during the grinding process. This paper describes the sensorintegrated grinding tool and shows the results of cutting tests.
cutting disc, monitoring, grinding, granite
To produce slabs and tiles out of natural stone abrasive cutting with circular tools is of primary importance compared to gang or rope saws. To improve the economy and ecology of abrasive cutting processes various approaches exist, such as the reduction of the tool width or the increase of the material removal rate via creep-feed grinding. Those approaches reach their limits due to tool deflection. Knowledge of the tool behavior within the process can improve the profitability of the grinding process. This information can be gained with the help of a tool monitoring system. The paper describes an approach to monitor the axial tool vibrations throughout the grinding process.
grinding process, abrasive cutting, processing quality, grinding-performance, material removal
Against the background of growing dynamics in the economic environment, new approaches to analyze and influence the dynamic behavior in production networks need to be found. The analysis of nonlinear dynamics can help to differentiate causes of the formation dynamics. A significant cause is the different logistic reactivity of the supply chain partners.
dynamic, production network, supply chain, supply chain management
Sheet metal parts often have to be connected by fasteners. Fasteners like bolts are mostly welded individually after the forming process and outside the working tool. This spatial separation of production steps requires complex handling operations and has negative impact upon the positioning accuracy of the fasteners. Every executable manufacturing step inside the sheet metal working tool shortens the process chain significantly. Furthermore, using a combined process the precision of position and orientation of fasteners improves. The challenges of integrating the welding process into the sheet metal working tool are handling the emissions and associated pollutions of the tool as well as creating a reliable monitoring-system for the welding-process. Within the scope of a research project, a reliable technology for the integration of condenser discharge stud welding with tip ignition was developed and tested. It complements existing solutions for integrated resistance welding processes.
sheet metal, capacitor discharge arc stud welding, cd arc stud welding, tip ignition, follow-on tool
Many forged parts include piercings e.g. as bearings. The web of the forged pieces has to be pierced in an additional manufacturing step. By integrating this so far separately performed operation into the final forging step the process chain can be shortened. However, up to date there is no information available on how the process parameters influence quality relevant factors. Therefore, a combined forging-/piercing process is designed and performed. The results of previous research projects showed that the variation of the inserted mass and the forging temperature have a distinct effect on the dimensional and form accuracy of the work pieces. In this project different punch and work piece geometries and the influence of a different forming sequence on tool stress and the material flow was investigated. The punch and work piece geometry show no effect on form accuracy of the piercing while an inappropriate forming sequence leads to failure of the tool.
forging, flashless, precision, piercing
