Improving engineering change processes by using lean principles
The purpose of this research was to test the usefulness of the 13 lean principles for product development by Morgan & Liker when improving an engineering change (EC) process.
The EC-process was studied at four firms. The firms were active in three different industrial branches. Two of the firms are situated in Sweden and two in Finland. First an exploratory single case study was carried out at one of the Swedish firms. This study was later merged into a multiple case study involving three more firms. The single case study included a thorough investigation on lead times in three explicit EC cases. The problems found in the EC processes in the multiple case studies were compared with the lean principles. If the problem caused a violation of one or several of the principles a solution to the problem was sought in line with the principle. From the results of the studies a synthesis was done to develop a lean Information Model to be used as a framework when improving information management aspects of engineering processes. The work was done in cooperation between Swerea IVF and Aalto University School of Science (previously Helsinki University of Technology).
Also a two case study was carried out involving one of the Swedish firms from the previous work and one other firm not involved in the previous work, both from the automotive industry. The purpose with this study was to study the transformation process to lean product development. The study was done in cooperation between Swerea IVF AB and Chalmers university of Technology. The result from this study was later compared with the lean principles of Morgan & Liker. The results from these studies are published in four papers and further developed in this thesis.
The results show that the lean principles can be used as a means to analyze and improve an engineering change process.
The conclusions are:
- There is a good match between the problems connected to ECs at the studied firms and the lean principles.
- Lean principles can be used as guidance when improving an EC process in the industrial context of this research.
- There were no contradictions found between improvements of an EC process and the lean principles.
- Lean principle one, six, eleven, twelve and thirteen explicitly and principle seven implicitly support transformation to Lean Product Development at a supplier of mechanical and electromechanical products in the vehicle industry.
- A better overview of ECs and a reduction of the time for information transfer are achieved when an EC process is designed according to the lean principles.