Abstract: Aiming at the quality control problem of wind turbine hub assembly process, a method is put forward that identifies and monitors the key process of hub assembly oriented to positioning, according to the characteristics of multi-variety small batch production mode. Considering the cost and relative quality loss in the assembly production of the wheel hub, the quality characteristic loss standard of the assembly process is proposed, and the improved Taguchi quality loss function adopted to identify the key process of the hub assembly. In order to solve the bottleneck of statistical process control (SPC) method applied to small batch production mode, the process similarity analysis and evaluation method is introduced based on intuitionistic fuzzy set, which means that by analyzing the influencing factors of process similarity, this method aims to establish a similarity evaluation index system and an evaluation model for the hub group process, which complete the measure of process similarity. Finally, the SPC method is used to monitor and manage the key processes of the hub assembly to ensure the assembly quality of the hub. This study provides a theoretical basis for the use of SPC methods to manage process quality in small batch production models.

Key words: key process, Taguchi quality loss function, multi-variety and small batch, intuitionistic fuzzy set, similar process, statistical process control (SPC)