According to the problems of quality data acquisition not in time, lacking of quality sample data in key process of multi-varieties and small-batch machining workshop, which lead to the difficulty for implementing dynamic SPC (statistical quality control) and early warning for quality status, a three-layer technical framework of dynamic SPC for key process in multi-varieties and small-batch machining workshop was proposed, which integrated real-time filed data acquisition, data transforming of small samples, quality status on-line controlling and early warning. Meanwhile, the key technologies for the framework were studied, including the dynamic quality data acquisition based on the multi-functional information interactive terminal, the multi-charts SPC method under condition of small samples, and the quality status early warning based on BP neural network. Finally, the method was applied in a machining workshop, and good results were obtained.
