Publications

In the automotive and mechanical engineering industries, forged parts are used in many applications. The dies for the forged parts are subject to high wear during forging due to high forming forces and temperatures. In order to enable economical production operation, methods to reduce the wear in warm forging have been investigated. One promising method is the use of Diamondlike-Carbon (DLC) wear-resistant coatings.

Warm Forging, Coating, DLC, Wear

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

What factors influence the running behavior of idlers? How do they behave in heat and cold; how resistant are they to water and dust? All this can be investigated with the new test rigs at IPH. Even motor-driven idlers are tested there.

idlers, rollers, test rig, belt conveyor system, bulk material handling, energy efficiency

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 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

Planning a factory is a major challenge, especially for small and medium-sized manufacturing companies that have little experience. We explain how factory planning projects work and which digital tools simplify and accelerate planning.

factory planning, analysis, structural planning, dimensioning, warehouse planning, layout evaluation

IPH has made it its business to integrate the core idea of sustainability into its mission statement – in research, but also in its daily work. 

In numerous research projects, the scientists are working on recycling plastics, reducing the energy requirements of vehicles, developing lightweight construction concepts, reducing waste in components produced by forming technology and intelligently integrating renewable energies into production – and for example they are also shedding light on questions relating to the environmentally compatible dismantling, repowering and new construction of wind turbines.

In addition, IPH and an interdisciplinary team of employees are committed to making the entire company more sustainable as part of the "ÖKOPROFIT" program.

sustainability, resources, environmental protection, economic efficiency

In Germany, demand for commercial drones is forecast to increase by 200% by 2025. As the use of drones increases, so does the danger they pose. This article describes a research project that aims to develop an acoustic operational monitoring system to improve the safety of critical components.

UAS, drones, operational 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

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

In the production of stock goods, manufacturing companies are faced with uncertain customer demand. In order to counter uncertainties, an increased inventory is necessary in order to be able to meet customer demand. The costs incurred are influenced by the ordering behaviour given the forecast uncertainty. Ordering behaviour is largely determined by the ordering policy. Therefore, the influence of forecast uncertainty and ordering policy on the resulting storage costs was investigated by means of sensitivity analyses. Accordingly, forecast uncertainties require larger inventories under the (t, S) policy than under the (s, q) policy.

stock planning, ordering policy, forecasting

Unmanned aerial systems have changed the industry dramatically. The rapidly advancing technological development of so-called Unmanned Aircraft Systems (UAS) makes it necessary to address the design of future operational scenarios at an early stage.

UAS, Drones, Navigation

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

Your contact person