GEOMETRICAL QUALITY FAILURE

Sammanfattning: The objective of this master thesis was to investigate if there is a relationship between geometrical quality failure cost and geometrical deviation from the designed target value. To achieve this objective this master thesis has defined what is referred to as geometrical quality failure and geometrical quality failure cost. Furthermore, to make it applicable for organizations this master thesis also has investigated how a potential relationship could be used. This master thesis was performed as a case study at the Swedish car manufacturer Volvo Cars Corporation, VCC. The case study included both a qualitative and a quantitative part. There were three main quantitative parts: questionnaires, a cost analysis and a geometrical analysis. The questionnaires were sent to recipients both within the VCC organization, also to external organizations and experts within the field of geometry assurance and geometrical quality. The responses from the questionnaires were used to define geometrical quality failure and geometrical quality failure cost. The cost analysis and the geometrical analysis were done with four samples, and investigated if there was a relationship between the defined geometrical quality failure costs and deviation from the designed target value. The qualitative part of the case study was used to find costs that were related to geometry within the VCC organization, and also to investigate how a possible relationship could be used in organizations. For the qualitative part, interviews were conducted both with individuals from VCC and external organizations. This master thesis showed that there was a relationship between the defined geometrical quality failure cost and geometrical deviation from the designed target for the investigated samples. It also argued that the relationship could be used as a communication tool within organizations. The relationship could also be used in negotiations to communicate that a more robust design, a supplier that delivers robust components, or a better assembly system could be cheaper from a long-term perspective. Furthermore, the relationship could also be used to communicate the importance of working with develop more robust designs. Keywords – Geometrical quality failure, Geometrical quality failure cost, Quality, Geometrical variation, Cost, Taguchi, and Quality loss function.