Background This research study is in collaboration with the Blekinge Institute of Technology and Volvo Cars Body Components (VCBC). VCBC is a car manufacturer that manufactures car body components in Olofström, Sweden. VCBC is also a supplier for Volvo Cars production sites around the world, which puts more responsibility on VCBC and their work process. One of the limitations of this research will be a focus on a production line for nut welding, where various projection welding features are present.   Objectives The objectives of the study are to investigate the problems with the production line and present a conceptual solution which can make the process more efficient and effective in terms of e.g. the cycle time, value-adding activities, improvements of traditional work processes or equipment, ergonomics safety, reduction of frequent errors, etc. Most of the objectives are influenced by principles in lean manufacturing theory but will be compiled and integrated with new innovative solutions that are influenced by digitalization and industry 4.0. Methods The methods and tools which will be used for this research will be primarily from process engineering and systems engineering. Autodesk AutoCAD, Siemens Process Designer PLM and Robot Load are some of the software that will be used. Some tools and strategies used for the methodological approach are e.g. The design thinking process, Six Sigma, FMEA, Question-Method-Matrix, Material flow analysis, and Value stream analysis. Results A concept layout solution was generated, which consists primarily of a model in Autodesk AutoCAD and a simulated prototype in Siemens Process Designer PLM. Through several analyzes, based on the objectives of the research, it has been conducted that the concept is more efficient than the current process. Specifications such as cycle time, production line area, value-adding activities, etc. have been improved drastically. Several innovative idea solutions based on digitalization and industry 4.0 were also generated by implementing them as a way of tackling the challenges with lean theories and develop the traditional work process in a factory. Conclusions The contribution of the research analysis is the implementation of lean theories together with modern strategies, tools and software are from systems engineering and process engineering together with ideation and problem-solving techniques. This itself has contributed to all goal objectives of the research study being achieved, assessed and validated.