Evaluating suppliers - A case study of plastic component suppliers at ABB Electrification Sweden AB

Sammanfattning: Choosing the right supplier is essential. Hence, supplier evaluation is of great importance for companies. However, it is associated with a high degree of complexity and is under-researched for plastic component suppliers. Therefore, this thesis studies supplier evaluation in the context of plastic component suppliers. Consequently, suitable elements (i.e., criteria) that can be used to evaluate suppliers, a scale that creates comparability by assessing the suppliers’ performances and weights that reflect the elements’ importance are identified. For the conducted research ABB Electrification Sweden AB, which operates in the field of electrical distribution and management, serves as the case company. While literature already offers an expansive list of elements used in supplier evaluation, this thesis establishes equitable elements for plastic component suppliers. This was done through interviews with experts from the case company. Throughout another round of interviews, the element values were accumulated and a scale was created to translate the values into a score. Finally, with the help of a questionnaire, the Best-Worst Method (BWM) in combination with the Simple Multi-Attribute Rating Technique (SMART) was used to attribute weights to the elements. The elements, scores and weights were combined through a scoring model and visualised in a framework, which displays the suppliers’ ranking. The thesis proposes two plastic component specific elements, namely plastic specific skills and measuring competence. Further suitable elements for an evaluation are summarised and validated through the research. Out of the proposed scoring methods, a scale from 1 to 4, which is independent from the suppliers, demonstrated to be valuable. While four weighting methods where examined, the combination of BWM and SMART proved to work well to assign the elements’ weights. An additional fundamental contribution of this thesis is a structured approach to supplier evaluation. This is especially useful, as one research finding is that relying on an expert’s gut feeling depicts a different supplier preference than a detailed evaluation.