Open this publication in new window or tab >>2018 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]
Remanufacturing is a product recovery option in which used products are brought back into useful life. While the remanufacturing industry stretches from heavy machinery to automotive parts, furniture, and IT sectors, it faces challenges. A majority of these challenges originate from the remanufacturing characteristics of having little control over the core (the used product or its part), high product variation, low product volumes, and a high proportion of manual work, when compared to manufacturing. Some remanufacturing challenges appear to be process challenges that prolong process lead time, making remanufacturing process inefficient.
Lean is an improvement strategy with roots in the manufacturing industry. Lean helps to increase customer satisfaction, reduce costs, and improve company’s performance in delivery, quality, inventory, morale, safety, and other areas. Lean encompasses principles, tools and practices to deal with e.g. inefficient processes and long process lead times. Therefore, in this thesis lean has been selected as an improvement strategy to deal with long remanufacturing process lead times.
The objective of this thesis is to expand knowledge on how lean can reduce remanufacturing process lead time. This objective is approached through literature studies and a case study conducted at four remanufacturing companies. There are five challenges that contribute to long process lead time: unpredictable core quality, quantity, and timing; weak collaboration, information exchange, and miscommunication; high inventory levels; unknown number of required operations in process and process sequence; and insufficient employee skills for process and product upgrade. When analysing the case companies’ process lead times it was found that there is a need to reduce waiting times, which account for 95 to 99 per cent of process lead times at three of the four companies.
To improve remanufacturing process efficiency and reduce remanufacturing process lead time six lean practices are suggested: product families; kanban; layout for continuous flow; cross functional teams; standard operating procedures; and supplier partnerships. The suggested lean practices have a key focus on reducing waiting time since it prolongs the process lead time. This thesis contributes to lean remanufacturing research with the case study findings on lean practices to reduce remanufacturing process lead time and increase process efficiency.
Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press, 2018. p. 70
Series
Linköping Studies in Science and Technology. Dissertations, ISSN 0345-7524 ; 1938
Keywords
Circular Economy, Lean Production, Toyota Production System, Value Stream Mapping, Remanufacturing Process Challenges and Improvements, Process Efficiency
National Category
Production Engineering, Human Work Science and Ergonomics Reliability and Maintenance
Identifiers
urn:nbn:se:liu:diva-147875 (URN)10.3384/diss.diva-147875 (DOI)9789176853030 (ISBN)
Public defence
2018-06-14, ACAS, A building, Campus Valla, Linköping, 09:15 (Swedish)
Opponent
Supervisors
2018-05-172018-05-172019-09-30Bibliographically approved