Process Oriented Production Evaluation

摘要

A company’ production at best is efficient, flexible and lean at the same time. Vice versa, a production is not well prepared for future challenges when changes and turbulences pose a serious danger to the performance of production processes or t here is too much waste instead of value-adding within a process. As lean principles and flexibility are hard to quantify, existing approaches evaluate either the efficiency or the implementation of lean principles, which are aimed at flexibility. However, as efficiency, flexibility and lean principles are partly competing objectives, an approach to evaluate a company’ production has to be focused on their interdependencies.As production not only includes the production processes themselves but also supporting processes, necessary for the production activities but not value-adding (e.g. maintenance, planning and controlling, administration), the consideration of these processes within the evaluation of the production is essential. Activity based costing enables a company to assess processes and calculate the different costs of different product variants within production support operations. The appropriation of production assets to the product variants occurs by the machine-hour rate. These approaches imply a predicted production program and associated costs. If the production program changes – in volume, allocation of volume between different variants and the number of variants itself – costs along the value stream will change. For example, a new production program requires an adjustment of lot sizes, work in process increases and thereby efforts for logistics and changeovers alter. Along the value stream it is also possible, that other bottlenecks anticipate the designated production program and require additional investments to achieve the intended output.This paper describes the principles of an approach evaluating the flexibility of the production processes to produce a changing production program (product variants and production volume) and its impacts on the cost curves of a complete value stream including its support processes with the help of activity based costing. It facilitates the evaluation of production’ efficiency as well as its flexibility to react on changing product variants and production volume. It also locates cost intensive processes that can be eliminated or reduced and shows effects on key performance indicators of lean principles, like throughput time and processing time.