Defects like folds can arise using forging for the production of long flat pieces made of aluminium. A special defect is the formation of inner folds. These can be seen in the grain flow. Inner folds have a negative effect on the dynamic properties of the forged part. As a production process, forging can be divided into single-directional and multi-directional forging. The formation of inner folds was observed at the single-directional forging. By using the multi-directional forging, a forming operation working from different directions, the forming can be set variably. Thus the development of folds can be prevented. A newly developed method can help in the selection of the forming process and in determining an appropriate tool geometry. Here especially the area is adapted, where the development of inner folds occur. Therefore a calculation model was developed. It integrates a computer-aided identification of the inner folds. Using this model, a correction of the parametrically constructed forging tool is possible.
multidirectional-forging, long flat pieces, aluminium, fibre orientation
Additive manufacturing has established itself in medical technology, where complex and patient-specific products are manufactured. Since additive manufacturing processes are sensitive to changes in process parameters and environmental conditions, quality assurance is a key factor for production. This paper presents the approach for in-situ process monitoring in additive material extrusion.
Additive Manufacturing, 3D printing, Fused Deposition Modeling, quality control, machine learning
Due to the increased integration of functions, many components have to meet high and sometimes contradictory requirements. One way to solve this problem is Tailored Forming. Here, hybrid semi-finished products are manufactured by a joining or cladding process, which are then hot-formed and finished. For the design of hybrid components for a possible later industrial application, knowledge about properties of hybrid components is required. In this paper it is investigated how the respective process steps of the Tailored Forming process chain change the surface and subsurface properties of the applied cladding layer. For this purpose, shafts made of unalloyed steel are provided with a high-alloy austenitic steel X2CrNiMo19-12 cladding by laser hot-wire cladding. Subsequently, hot forming is carried out by cross-wedge rolling and the finishing by turning and deep rolling. After each process step, the subsurface properties of the cladding such as microstructure, hardness and residual stress state are examined. Thus, the influence of different process steps on the subsurface properties in the process chain of manufacturing hybrid shafts can be analyzed. This knowledge is necessary for the specific adjustment of defined properties for a required application behavior.
Cross-Wedge Rolling, Tailored Forming, Hybrid
During the assembly of large-scale products, disruptions often occur. To reduce these disruptions, a straightforward approach to their systematic processing is needed. This should automatically identify similar disruptions and independently suggest sensible corrective measures. For this, the disruptions are first collected and characterized and a model for practical information flows is created. Then, in a multi-stage similarity search, similar disruptions are identified, and suitable corrective measures are derived.
Disruption management, single and small batch assembly, large scale products, similarity search
In this paper, a new solution for the facility layout problem is presented. The approach was integrated into a planning software. The aim of the MeFaP research project was mainly the development of a user-friendly decision support regarding the facility layout problem for small and medium-sized companies. Therefore, a realistic modelling of the planning problem was focused on. Thus, a path planning with area allocation was integrated, for example. The metaheuristic Tabu Search was selected as a solution approach. To ensure an efficient optimisation, the optimisation is performed in two steps, once without and then with route planning. The experiments were performed with the objectives material flow distance, temperature and cleanliness, which are briefly described. The results of the experiments were compared with current solution approaches.
facility layout problem, factory planning, multi-criteria, metaheuristic, tabu search, software
Reducing the planning and development time for efficient staging sequences in closed die forging offers companies in the forging industry a high potential for responding to competitive to respond to competitive challenges and remain competitive.The digitization of development processes opens up innovative support options for companies.
forging sequence desing, forming technology, digitization, process development, CAD
In order to enable even complex processes such as the joining of additively manufactured components by laser in production in a quality-assured way, the existence of specialist knowledge in companies is absolutely essential. To bundle this knowledge for process control and monitoring independently of personnel, an expert system is being developed in the IGF research project of FQS - Forschungsgemeinschaft Qualität e.V. entitled "Quality assurance in laser beam welding of additively manufactured thermoplastic components (QualLa)". By integrating specialist knowledge into the expert system, this knowledge can be secured in companies in the long term and processes can continuously be carried out with high qualitative standards.
additive manufacturing, 3D printing, FDM, laser transmission welding, laser beam welding
In the forging industry, which is dominated by SMEs, the tool life of forging dies is usually determined on the basis of empirical values and subjective decisions. In order to avoid considerable logistical and economic expenses as a result of unplanned downtimes and die failure, the tool life is often set many times lower and a waste of existing residual tool life is caused. One possibility to determine the remaining tool life of forging tools is a combined measuring method, which is to be developed at the Institut für Integrierte Produktion Hannover (IPH) gGmbH.
Forming technology, tool life, process monitoring
The manual handling of forged parts is physically demanding for forging employees. These physical stresses are reflected in damage to the hand-arm system and back and lead to forging employee absenteeism. In order to protect the health of forging employees, the aim is to reduce the basic stress caused by the dead weight of the forging tongs by using lightweight forging tongs.
forging tongs, ergonomics, lightweight design
Flat die rolling is a solid forming operation, in which two engraved tool plates run past each other and thereby form a cylindrical semi-finished product. The non-circular rolling can be used as a preform optimising process, where it should be possible to form local non-circular sections, for example ellipses or eccentrics, into a cylindrical semi-finished product. The material flow should be exclusively in radial direction. Initial simulations show that the requirements can be met.
non-circular rolling, cross wedge rolling, flat dies, preforms and intermediate forms, FEM
The development of a method for the optimal planning of the relocation of factory objects is being addressed by the IPH - Institut für Integrierte Produktion Hannover gGmbH within the framework of a research project. The design of a relocation plan, taking into account temporal and spatial restrictions, represents a complex planning problem. The method to be developed enables a comprehensive evaluation of a relocation plan with regard to different target criteria. The mathematical optimisation model is to be implemented with the help of a heuristic solution procedure. The intuitive implementation within a software environment further supports the easy applicability.
Factory Planning, Relocation, Project Scheduling, Preparation for Realisation, Operations Research
Since free?aces for new buildings are limited or not available at all, redensification is a promising approach to generate new living space. This can be both the extension of existing buildings by further storeys and the vertical extension or change of use of other building structures. Modular house construction takes this objective into account because a large part of the added value is generated before construction begins. Its advantages are now set against the logistical challenges of post-densification.
Modular house construction, post-densification, construction sites, production planning and control
On inner-city construction sites, there is usually only a limited amount of space available. This increases the complexity in the implementation of corresponding construction projects and at the same time the risk of postponements. Both the composition of the demand for specific types of space and the development of demand during the construction period should be taken into account in the course of scheduling. One way of assessing the demand for space is to introduce the potential for conversion as an indicator of the property of a specific space to be able to adapt flexibly in the event of possible short-term changes in the construction project. This can be used to create an evaluation basis that initially provides decision support for project planners and can subsequently be integrated into optimising procedures for scheduling. This will have a positive influence on the quality of a schedule in connection with its robustness.
Scheduling, construction management, project planning, production planning, construction sites
Multi-stage forging process chains are often used for the efficient production of complex geometries. Typically, these consist of homogeneous heating, one or more preform stages, and the final forging step. By inhomogeneously heated billets, the process chains can be simplified or shortened. This shall be achieved by setting various temperature fields within a billet, resulting in different yield stresses. These can influence the material flow, leading to easier production of complex parts. In this study, the influence of inhomogeneously heated billets on the forming process is investigated by means of FEA. For this purpose, two process chains including inhomogeneous heating and three homogeneously heated reference process chains are developed and compared. Each process chain is optimized until form filling and no defects occur. Target figures for the assessment are necessary forming force, the amount of material necessary to achieve form filling and die abrasion wear. For process chains with inhomogeneously heated billets, the results showed a small time window of about 5 s for a successful forming in terms of form filling. Forming forces and die abrasion wear increase for inhomogeneously heated billets due to higher initial flow stresses. However, the flash ratio decreases when billets are heated inhomogeneously. Depending on their size, inhomogeneously heated billets show up to 11.8% less flash than homogeneously heated billets. This shows a potential for the use of inhomogeneous heating to make forging processes more efficient. Subsequently, experimental tests will be carried out to verify the results of the simulations.
Inhomogeneous heating, Forging, FEA, Resource efficiency, Preform operation
To increase the economic efficiency in the production of geometrically complicated forgings, material efficiency is a determining factor. In this study, a method is being validated to automatically design a multi-staged forging sequence initially based on the CAD file of the forging. The method is intended to generate material-efficient forging sequences and reduce development time and dependence on reference processes in the design of forging sequences. Artificial neural networks are used to analyze the geometry of the forging and classify it into a shape class. Result of the analysis is information on component characteristics, such as bending and holes. From this, special operations such as a bending process in the forging sequence can be derived. A slicer algorithm is used to divide the CAD file of the forging into cutting planes and calculate the mass distribution around the center of gravity line of the forging. An algorithm approaches the mass distribution and cross-sectional contour step by step from the forging to the semi-finished product. Each intermediate form is exported as a CAD file. The algorithm takes less than 10 min to design a four-stage forging sequence. The designed forging sequences are checked by FE simulations. Quality criteria that are evaluated and investigated are form filling and folds. First FE simulations show that the automatically generated forging sequences allow the production of different forgings. In an iterative adaptation process, the results of the FE simulations are used to adjust the method to ensure material-efficient and process-reliable forging sequences.
Automatic process design, Forging, FEA, Resource efficiency, CAD
A method is presented that enables the complexity of a forging to be determined automatically on the basis of the CAD file of the forging. An automated evaluation of the forging complexity is necessary for a digitized and automated design of stage sequences in order to be able to determine important design parameters such as the flash ratio or the number of stages.
CAD, forming technology, algorithms
The compilation of information for the processing of internal production tasks is often based on less-questioned route sheet templates. The selection of the optimal amount and depth of information requires a positioning in an area of conflict between the amount of work in the planning process and the benefit in the execution. Therefore, a method to quantify and evaluate the level of detail of different information individually is presented. Thus a basis is created to determine the optimal level of detail in route sheets.
route sheets, work preparation, level of detail, provision of information, MES-implementation
Qualitative uncertainties are a key challenge for the further industrialization of additive manufacturing. To solve this challenge, methods for measuring the process states and properties of parts during additive manufacturing are essential. The subject of this review is in-situ process monitoring for material extrusion additive manufacturing. The objectives are, first, to quantify the research activity on this topic, second, to analyze the utilized technologies, and finally, to identify research gaps. Various databases were systematically searched for relevant publications and a total of 221 publications were analyzed in detail. The study demonstrated that the research activity in this field has been gaining importance. Numerous sensor technologies and analysis algorithms have been identified. Nonetheless, research gaps exist in topics such as optimized monitoring systems for industrial material extrusion facilities, inspection capabilities for additional quality characteristics, and standardization aspects. This literature review is the first to address process monitoring for material extrusion using a systematic and comprehensive approach.
Material extrusion, Fused deposition modeling, Process monitoring, Sensor technology, Research gaps
Software for an Automated Multidimensional Factory Layout Optimisation: Layout planning is a complex planning task in the context of factory planning, which up to now has usually needed to be carried out manually. Although many optimisation methods for the underlying problem have been developed in the past, they were only applicable to a small group of experts, mostly from universities. Therefore, an easy-touse software for layout planning was developed in a research project to provide companies with access to these optimisation methods.
Factory planning, facility layout planning, optimization, operations research, software
The machine learning based method for layout optimization of smallscale modular conveyor systems, which is developed within a research project at IPH – Institut für Integrierte Produktion Hannover gGmbH, provides SMEs a decision support, which enables them to execute complex layout planning independently. In addition, the machine learning method is intended to reduce the cost and time required for planning and to improve the quality of the solution compared to manual layout design.
Small-scale modular conveyors, conveyor systems, machine learning, artificial intelligence
Maturity-based Evaluation of Requirements for a Successful MES Implementation. The use of a Manufacturing Execution System (MES) can offer many advantages for companies, but the implementation often poses a great challenge. The determination of necessary requirements, their fulfilment by the company and their consideration in the implementation process are decisive for a successful implementation. In the following article, the development of a maturity-based method for the evaluation and improvement of the companyspecific fulfilment of the requirements of an MES implementation is presented.
Manufacturing Execution System, Maturity Model, Digitalization
