Today most technical parts and components are made of monolithic materials. Nevertheless, the previously used monolithic materials reach their technological and constructive limits, so that an improvement of the component properties can be realized by hybrid parts. Forging of previously joined semi-finished products to net shape hybrid components is a promising method to produce functional adapted parts in a few process steps. This new process chain offers a number of advantages compared to other manufacturing technologies. Examples are the production of specific load-adapted forging parts with a high level of material utilization, an improvement of the joining zone caused by the followed forming process and an easy to implement joining process because of the simple geometries of the semi-finished products. This paper describes the production process of hybrid steel parts, which are produced by a combination of a deposition welding process with a subsequent hot forging (upsetting) or cross-wedge-rolling. It could be shown that the innovative process chain enables the production of hybrid parts whereby the forging processes lead to an improvement of the mechanical properties of the laser deposited material.
process chain, deposition welding, hot forging, cross-wedge-rolling
The production of large-scaled products is often associated not only with great challenges, but also with enormous costs. The way how the product is designed offers the greatest potential for cost reduction. At the IPH, engineers are currently developing a new modular design for XXL products.
xxl products, modular design
Within the research project "Intelligente Schmiedewerkzeuge zur Fehlerreduktion in der Massivumformung" (AiF 17009 N) intelligent forging tools and a specific software were developed which allow an identification of forged errors and a mold filling monitoring. This article presents the underlying concept and the developed software.
forging, process monitoring
Planning in a multi-site, non-mass production environment is a special challenge because of several sources of uncertainty. Unlike in mass production facilities, in our setting the current state is not easily and exactly known when the case of re-planning occurs. The planning procedure has to contribute to that fact, as well as to further uncertainties concerning the effects of a plan when evaluating the plan. Thus in this work, we apply online simulation as means for re-planning multi-site production in the case of resource failure. This work is a first step where two alternatives are considered when a resource fails: either wait for repair of the resource, or transport another instance of this resource from another site, if there is more than one available. Our study shows that the planning using online simulation is superior to a static strategy such as 'always wait for repair' or 'always import resource' in case of resource failure.
assembly control, simulation, production planning and control, failure management
The energy costs‘s share in the total is increasing in producing companies. Due to variations in the energy consumption over the day, arising power peaks lead to high energy costs. Power peaks could be reduced by load management systems. But these systems could have a negative impact on logistic performance figures. A simultaneous optimization of logistic performance figures and the energy consumption is not available yet. In this article a method for the energy cost-based production scheduling is presented. This method schedules jobs on machines in a way that the energy consumption is equalized and the logistic performance (makespan, stock, job delays, workload) is ensured.
energy costs, power peaks, production scheduling
The energy costs‘s share in the total is increasing in producing companies. Due to variations in the energy consumption over the day, arising power peaks lead to high energy costs. Power peaks could be reduced by load management systems. But these systems could have a negative impact on logistic performance figures. A simultaneous optimization of logistic performance figures and the energy consumption is not available yet. In this article a method for the energy cost-based production scheduling is presented. This method schedules jobs on machines in a way that the energy consumption is equalized and the logistic performance (makespan, stock, job delays, workload) is ensured.
energy costs, power peaks, production scheduling
The energy costs‘s share in the total is increasing in producing companies. Due to variations in the energy consumption over the day, arising power peaks lead to high energy costs. Power peaks could be reduced by load management systems. But these systems could have a negative impact on logistic performance figures. A simultaneous optimization of logistic performance figures and the energy consumption is not available yet. In this article a method for the energy cost-based production scheduling is presented. This method schedules jobs on machines in a way that the energy consumption is equalized and the logistic performance (makespan, stock, job delays, workload) is ensured.
energy costs, power peaks, production scheduling
The usable wind energy increases exponentially by increasing the height of wind turbine generators. The material requirements and the tower weight increases disproportionately high by growing tower height. In current designs, the height of towers is limited. The application of lightweight design concepts in the production of wind turbine tower sections can lead to a reduction in the weight with the same tower stiffness. Therefore lightweight designs have great potential to increase wind turbine efficiency. In this paper, the results of the research for lightweight concepts and their implementation on towers and a guiding systematic approach are presented. As part of the research, design concepts have been developed. These design concepts allow the mass reduction, with constant stiffness, for the wind turbine towers on land (onshore). Several investigation loops of these lightweight designs were run. Different concepts of bionics, aviation, aerospace and automotive have been investigated for their suitability in wind turbine towers. A suitable concept was identified based on trapezoidal sheets. Using these sheets, the weight of towers can be reduced by 20 %.
xxl-product, large-scale, xxl, wind turbine, wind power, lightweight construction, tower constructio
At the Institut für Integrierte Produktion Hannover gGmbH (IPH) a method is currently being developed, that supports the controlling of logistical targets and associated logistics costs in the supply chain for the assembly of wind energy plants. The considered supply chain comprises all steps from the production of the individual components up to the handover to the customer. The method enables continuous prediction whether date variances have a critical monetary and scheduling impact on the project success.
material provisioning, site assembly, cost controlling, schedule deviation, early warning system, fo
Indoor positioning is the backbone of many advanced intra-logistic applications. As opposed to unified outdoor satellite positioning systems, there are many different technical approaches to indoor positioning. Depending on the application, there are different trade-offs between accuracy, range, and costs. In this paper we present a new concept for a 4-degree-of-freedom (4-DOF) positioning system to be used for vehicle tracing in a logistic facility. The system employs optical data transmission between active infrastructure and receiver devices. Compared to existing systems, these optical technologies promise to achieve better accuracy at lower costs. We will introduce the positioning algorithm and an experimental setup of the system.
optical indoor positioning, data transmission, signal processing, image processing, flexible warehou
In multi-site assembly, problems such as defective tools often cause delays. In order to avoid deferred deliveries and increased costs, assembly control is required to promptly determine a new assembly plan. A research project aims to develop a software support system which assists assembly control in the replanning process by applying online simulation to quickly identify possible plan alterations and evaluate their expected impact on logistical key figures.
assembly control, simulation, production planning and control, failure management
In this paper the development of the new production technology hybrid forging is described. Hybrid forging combines forming of bulk and sheet metal-elements including joining. Using three model experiments the joining by material bond and by form closure is analyzed. The form closure works like a riveting and the experiments showed good results. But not in every area of the specimen a material bond was present.
hybrid, forging, sheet metal forming, joining technology, steel, adhesive bond
The strength/density ratio of aluminium can be increased significantly by the integration of ceramic particles in the metal matrix, so called Aluminum MMC. Because machining of MMCs is very expensive due to the high hardness of the ceramic particles precision forging of Aluminum MMCs allows the high quantity production of near net shape components with a strength/density ration. The paper describes the development of a precision forging sequence for a demonstration made of Aluminum MMC.
aluminium metal matrix composites, flashless forging, FEA
In a research project by the Institut für Integrierte Produktion Hannover (IPH) and the Institute of Metal Forming Siegen the basics for hydroforming titanium tubes were investigated. The aim of this research project was to develop a multi-stage process chain for hydroformed parts made of titanium. First the method-specific material properties as well as the tribological system were examined. The results were combined in a simulation model which enabled the process development. Finally, the developed process chain was successfully tested using a real component and the trials were compared with the simulation results.
hydroforming, FEA, titanium
Due to high mechanical loads the die cavity shows high wear in warm forging processes. Within this paper the ability of a hydrogenated amorphous carbon doped by 40 % chromium as wear protective coating for bulk forming processes will be analysed. Therefore billets with temperatures between 650 and 1200 °C have been forged on this layer. Thereafter the layers are analysed and the wear behaviour is evaluated.
coating, forging, forming
The early detection of defects in forged parts offers economical advantages due to the possibility of sorting them out of the process chain. The detection of defects during the forging process is not state of the art. Due to the rough conditions in forging (e. g. high temperatures and forces) the integration of sensors monitoring the forging process is hardly viable. Usually defects of forged parts – which are not obvious and can therefore hardly be identified by the press user – are detected by measurements after cooling or later by the customer. In both variants costs occur. Within the presented research project an in-situ forging process monitoring is developed which works without sensors and shows results directly after forging.
metal, steel, metal processing, forging, quality
The early detection of defects in forging processes offers economic benefits. For example, workpieces that are forged incorrectly can be discharged from the process chain immediately and thus do not cause additional process costs, i. e. in a subsequent heat treatment. The development of a novel process monitoring using electrical current allows the identification of forging defects and underfillings.
forging, process monitoring
The higher mechanical loads in warm forming processes lead to increased mechanical wear of the dies. Using hard Diamond-like Carbon (DLC)-coatings can reduce this main disadvantage of warm forging. By an adequate doping of DLC with elements the temperature stability of these coating can be increased. Especially in areas with high relative movement the analysed coatings show advantageous behaviour compared to not coated dies.
diamond-like carbon (DLC), warm forming, bulk forming, wear
Forged parts have geometrical fluctuations for example caused by die wear. The investigation of a controlled, movable flash gap by FEA for compensation purpose showed how far the material flow can be varied during the forming operation. A potential to improve forging results is derived.
forging, die design, material flow, FEA, flash land
Hydroforming is often used to conduct forming of thin-walled hollow parts made of tubes. In order to form thick-walled hollow parts made of Aluminum a process has been developed, to form such parts. These parts are in a heated state. The forming has been made by help of an active fluid medium on a hydraulic deep-drawing press. For investigation purpose an example process has been designed for a trial part. This process has been analyzed by FEA and verified by laboratory tests.
hydroforming, forging, tubes, aluminium, FEA
