The production ramp-up is often a critical period for manufacturing companies. It is essential to prepare an efficient plan and to monitor consistently the abidance of this plan. With a maturity level model and key figures the quality of a ramp-up can be described. Therefore, the values of the key figures are categorized into maturity levels. By different aggregation levels a target-actual comparison can be made based on one key performance indicator.
production ramp-up, maturity model, aggregation logic, ramp-up management
Elimination of waste is the basis of the Toyota production system as well as any other lean implementation. Visual Management supports the process of waste elimination within the company. It helps to detect deviations from standards that indicate problems which should be solved by the means of continuous improvement processes. The article describes the basics of Visual Management and introduces selected methods such as 5S. In order to show practical implementation aspects a use case of Siemens AG is presented.
visual management, lean production systems, lean management, waste elimination
In multi-site assembly, problems such as defective tools require assembly control to react promptly in order to avoid negative consequences, such as deferred deliveries or additional costs. A method is presented which uses statistical online simulation based on structured assembly plans to quickly identify and evaluate possible options for dealing with a problem. Furthermore, the structure and procedure of a purpose-built simulation system is shown in this article.
assembly control, simulation, production planning and control, failure management
Reducing die wear is an effective way to decrease costs within bulk forming processes. Therefore, specific tool materials and heat treatments as well as special coatings are used to prolong the lifetime of the tools. Diamond-like carbon (DLC) coatings show high hardness and superior frictional behavior. However, these coatings seem to be inappropriate for hot forming due to degradation processes at elevated temperatures. But for warm forming, due to the lower temperature input into the cavity DLC might be an appropriate coating. Friction influences the shear stresses on the cavity surface and is therefore an important factor for reducing die wear. Hence, the frictional behavior of DLC coatings within warm forming will be analyzed within this paper by using the ring compression test. An amorphous hydrogenated carbon coating and six metallic doped amorphous hydrogenated carbon coatings (Cr, V and W each in two variants) are compared to CrN and no coating. Firstly, nomograms are graphed by the use of Finite-Element-Analysis. Thereafter two test series are carried out varying forming temperature and lubrication. The results show that DLC coatings with and without metallic doping are able to reduce friction in warm forming. Within the investigations an amorphous hydrogenated carbon doped with 15 % chromium shows the lowest friction factor and is able to reduce the friction factor compared to no coating by up to 64 % within warm forming.
diamond-like carbon (DLC), friction, warm forming, bulk forming, ring compression test
The challenge in developing a hydroforming process for Tailored Hybrid Tubes is to provide feasible forming conditions for both the steel and the aluminum part of the semi-finished hybrid material. The aim of these investigations is to develop one-stage tube hydroforming processes for steel-aluminum-joints. Therefore, the effects on the materials’ forming behavior, especially the flow stress, of the parameters alloy, thickness, forming rate and seam design are being investigated. Forming tests were carried out on sheet metal specimens of joined steel and aluminum to investigate the impact of the varied parameters and to analyze the joint area’s forming behavior. Based on the results of the forming tests an FEA-simulation will be set up in order to design a hydroforming process for Tailored Hybrid Tubes of laser joined steel and aluminum. Eventually the hydroforming process of Tailored Hybrid Tubes shall be executed for a sample part.
hydroforming, automotive, laser brazing, laser soldering, steel-aluminum, car body, engine downsizin
Hot forging dies are subjected to high mechanical, thermal and chemical loads. These loads can lead to die failure and therefore are one of the main cost factors in forging industry. The billet temperature is the process parameter mainly influencing the loads in forging processes. In warm forging the billet temperature is much lower than in hot forging. Warm forging becomes more and more important due to the advantages against hot and cold forging. This paper describes an analysis of FE-simulations of the change in loads on forging dies and the effect on the die life time by changing from hot to warm forging processes. Furthermore a method is presented which enables a calculation of thermal stresses in forging processes.
warm forging, hot forging, thermal stresses, tool wear
The production ramp-up is often a critical period for manufacturing companies. With a developed method for planning and monitoring of production ramp-ups at new locations this critical period becomes manageable. The method consists of reference processes, key figures and reactions. By different aggregation levels a target-actual comparison can be made to identify appropriate reactions.
production ramp-up, maturity model, aggregation logic, ramp-up management
Using hybrid forging techniques, both bulk or sheet metal can be formed and joined in a single step, rendering subsequent joining processes unnecessary. Moreover, using sheet metal rather than bulk material means that material-savings can be made and/or more economical forming units can be used.
hybrid, forging, sheet metal forming, joining technology, steel, adhesive bond
The production of a flashless crankshaft consists of four steps: cross wedge rolling, lateral extrusion, bi-directional forging and final forming. One improvement is to shorten the process by leaving out the lateral extrusion which leads to different faults as folds and flash. To investigate the influence of the cross wedge rolling on the bi-directional forging serval process parameters as forming angle and offset of the axis were varied. The purpose is to find a parameter field in which to faults occur.
cross wedge rolling, multi-directional forging, crankshaft forging without flash
There is a high potential for optimization in positioning a forging company’s tool supply between logistic costs and performance. Based on a model, which was developed for the improvement of the internal tool supply in the transfer project T13 of the CRC 489, a controlling instrument has been deduced to relate the weighted service level and the stock of the tool supply cycle.
production planning and -steering, production management, tool inventory reduction, servicelevel, fo
Designing a road layout for automated guided vehicles (AGV) can be a very laborious process that is based in big parts upon the knowledge of experienced system planers. Up until now, it isn’t possible to save that knowledge in a form that makes it usable in an automated layout process for AGV- roadmaps. The research project aims to integrate the knowledge of the system planers in an artificial intelligence, so that in the future an automated process of designing AGV roadmaps is achievable. The knowledge is implemented within a fuzzy-logic and can be used as a controller for the planning process.
automated guided vehicles, expert system, fuzzy logic, fuzzy logic controller
Intensive research work on flashless precision forging of steel materials has been made at the IPH in the past. In aluminum forging processes a thin flash often occurs in the gap areas between the forming elements. This thin flash adversely affects the component quality. For this reason flashless aluminum forging previously could not be realized. In this publication, the approach for the investigation of the thin flash formation is explained. A FEM model of a one-stage upsetting process in a closed die has been created. With this model the influence of the parameters workpiece temperature, forming velocity, the wideness of the flash gap and the pressing forces on the thin flash formation can be examined. Owing to these research activities a possibility for aluminum forging without flash and thin flash shall be provided.
flashless, forging, thin flash, aluminum, FEA
Rising costs for electricity endanger the competitiveness of the German industry. If the volatility of electricity prices and fluctuating energy consumptions are used purposefully by the manufacturing control, a reduction of energy costs without capital-intensive investments is possible. In this context the following article describes the development of a sequencing method considering work order-specific energy costs.
time variable electricity prices, fluctuating energy consumptions, manufacturing control, sequencing
The first challenge in the planning process of production systems is the creation of a rough draft of the system with minimal time and cost. From this an offer for the customer is then derived. This article describes a model-based approach for rough planning and its demonstrative implementation. The approach allows modeling at a high abstraction level. This reduces the modeling effort, the possible modeling errors and the documentation effort considerably.
production system, operations planning, performance prediction, simulation, variant documentation
The complaint handling suffers from defective 8D-reports. Hence the costumer supplier relationship is also affected. A system for the formal and substantive evaluation of 8D-reports will be developed in a research project. The aim is to improve the complaint processing due to high quality 8D-reports.
8d-method, 8d-report, claims management, complaint, quality management
Preforming is an essential step in flashless forging processes. This paper describes the development of a four stage process chain for flashless forging of a crankshaft with pin and flange. The process consists of cross wedge rolling, lateral extrusion, bi-directional forging and final forming. The finite-element-analysis (FEA) performed with the software Forge 3 and experimental tests are executed with different process parameters, like billet and tool temperature, rolling velocity and steel. To reduce process steps, like lateral extrusion, a direct combination of cross wedge rolling and bidirectional forging is analysed with FEA-software Forge 3 for a one cylinder crankshaft without pin and flange. The results of the FEA give suitable forming angles alpha for cross wedge rolling and several geometric parameters for a modification of the bi-directional tool.
cross wedge rolling, bi-directional forging, crankshaft forging without flash, preforming
By leveraging the production factor "human" it is possible by taking into account human performance fluctuations during the day to reduce product-related defect costs and increase quality. To this end, the integration of human performance variations in methods of production planning and control must be carried out. This article introduces a method by which a quality-oriented job shop schedule can be created, taking into account human performance fluctuations.
produktion planning, job shop scheduling, human performance fluctuation, optimization problem
Will the freight depot still be large enough in ten years – or is it necessary to built new rails? An austrian company wanted an answer to this question – and IPH was able to help with a detailed material flow simulation.
material flow simulation, railway traffic
An analysis of lifecycle data offers the potential to identify product weaknesses and starting points for product innovations. The paper describes a concept to analyze lifecycle data using predefined analyses and interactive searches. Moreover, a concept to integrate the results of the data analysis into an existing software environment is presented.
data-mining, life-cycle-data, data analysis, knowledge akquisition
While definitions already exist for smaller scale device structures e. g. nanotechnology, the conceptual distinction between standard large products and large scale or XXL products is currently insufficient. This study presents a basic definition of large scale products. At first hypotheses are being derived and examined at an empirical study of three sample products threaded nuts, screw presses and passenger aircrafts. It will be shown that the transition from conventional products to XXL large scale products is characterized by a disproportionate increase in the ratio of product costs to the augmentation of a characteristic product’s feature. Based on the results a definition for the characterization of large scale products is established referring to the technical, organizational and economical restraints and to the available processes and tools.
xxl-product, large-scale, xxl, definition
