Stefan Tönissen

Integrative Production Technology for High-wage Countries

Manufacturing companies in high-wage countries are increasingly set under pressure in international competition due the lower production costs in low-wage countries. In order to counteract this development, many manufacturing companies respond to this issue by relocating their production facilities. Due to industrial production’s high dependence on other sectors such as the services sector, this trend threatens Europe’s medium and long term prosperity since outsourcing generally leads to subsequent relocation of services as well as of research and development activities (Lau 2005). With over 40% of German employees assigned to the manufacturing sector, production plays a key role in the national economy of Germany. Consequently, relocation of production poses huge risks for the country’s future economic development (Statistisches Bundesamt 2010).

Integrative Produktionstechnik für Hochlohnländer

Produzierende Unternehmen in Hochlohnlandern werden im internationalen Verdrangungswettbewerb immer starker durch die augenscheinlich im relativen Vergleich niedrigeren Produktionskosten in Niedriglohnlandern unter Druck gesetzt. Um dem entgegenzuwirken, reagiert eine grose Anzahl produzierender Unternehmen mit einer Verlagerung der Produktionsstatten. Auf Grund der starken Abhangigkeit weiterer Wirtschaftsbereiche (wie beispielsweise der Dienstleistungsbranche) von der industriellen Produktion, gefahrdet dieser Trend mittel- und langfristig den Wohlstand in Europa. (Lau 2005) Produktionsverlagerungen fuhren in der Regel auch zu nachfolgenden Verlagerungen von Dienstleistungs-, aber auch von Forschungs- und Entwicklungstatigkeiten. Da uber 40 % der sozialversicherungspflichtigen Erwerbstatigen in Deutschland dem produzierenden Gewerbe zugerechnet werden, nimmt die Produktion eine Schlusselrolle ein und ihre Abwanderung birgt immense Risiken fur die Entwicklung der Volkswirtschaft des Landes. (Statistisches Bundesamt 2010)

Modeling economic efficiency of multi-technology platforms

It is believed that for complex workpieces and small lot sizes complete machining with multi-technology platforms reduces cycle times compared to multiple stand-alone machines and is economically more efficient. However, so far in literature no mathematical model has been applied to compare these alternatives with respect to cost and productivity. This paper introduces a mathematical model for part costs and productivity and examines conditions under which multi-technology platforms are economically efficient. It is concluded that depending on the reduction of reconfiguration and processing times efficient production with multi-technology platforms is not solely limited to small lot sizes.

Economic efficiency of manufacturing technology integration

Abstract Manufacturing technology integration is an emerging paradigm that focuses on the functional integration of diverse manufacturing technologies into machine tools. This paper describes the application of models of production, cost, and queuing theory to identify conditions under which manufacturing technology integration yields greater productivity, lower cost, and decreased throughput times than a manufacturing system comprising conventional single-technology machine tools. It was found that manufacturing technology integration is particularly cost- efficient for small output quantities. However, although the logistic chain is shortened through manufacturing technology integration, throughput times might increase because of waiting times.

Residual stress prediction in quick point grinding

The paper investigates the dependency of residual stresses on process parameters of grinding in the quick point mode. It is evaluated whether the area-specific grinding power or energy is correlated to the residual stresses in the surface and to the maximum residual stresses in the surface layer. Firstly, the paper derives an analytical model for the area-specific grinding power and energy based on models from literature. Secondly, the residual stress distribution of workpieces machined under varied cutting conditions is depicted for each process point. It is found that the area-specific grinding energy is correlated to residual stresses whereas the area-specific grinding power is an unsuitable residual stress predictor. Due to the limited experimental scope future research should seek to validate the findings with a broader variation of process conditions in quick point grinding.

Modeling the characteristics of multi-technology platforms

Multi-technology platforms are an emerging and promising production technology. However, until now the conditions are unclear under which value creation with multi-technology platforms can be carried out more efficiently than with a system of stand-alone machines. This paper derives characteristic thresholds mathematically that describe points of equal advantageousness of both alternatives in terms of lot size and number of processes required to machine the workpiece. It is found that the progression of the characteristic thresholds is describable by three characteristic figures χ, ρ and ω. The findings emphasize the necessity of a significant reduction of processing times on multi-technology platforms.

Multi-technology Platforms (MTPs)

The growing demand for individualized commodities requires new solutions for a highly flexible yet cost-efficient production. Hence, the research results described in this chapter address the question of how different manufacturing technologies could be combined and employed efficiently in industrial practice. Reaching across the whole field of Multi-Technology Platforms (MTPs) a generalized design methodology was examined. The resulting template-based procedure, combining function structure and technology chains, is introduced in the first section. Consecutively, the next section advances this approach by illustrating the incorporation of metrology into machine tools and MTPs. For technological validation, all newly-developed scientific approaches were successfully integrated into four demonstrator test beds located at the RWTH Aachen University: a Multi-Technology Machining Center, a Hybrid Sheet Metal Processing Center, a Conductive Friction Stir Welding Center and a laser-enhanced hybrid lathe. The economic efficiency of manufacturing technology integration is reviewed before a profitability assessment based on the aforementioned demonstrator test beds is performed. The chapter concludes with an outlook on future research topics.