A Conceptual Process Architecture for the Digital Integration of Tube Fabrication in Mechanical and Plant Engineering

In mechanical and plant engineering practice, tube fabrication is still frequently characterized by assembly-driven and experience-based procedures. Geometric specifications are often finalized during assembly based on measurements taken on the physical product, resulting in iterative adjustments, limited process standardization, and a strong dependence on tacit expert knowledge. Although advanced computer-aided design (CAD) and computer-aided manufacturing (CAM) technologies and automated tube bending systems are available, a structured integration of tube fabrication into a consistent digital process architecture is often lacking. This paper develops a conceptual process architecture that structures the digital integration of tube fabrication in project-driven mechanical and plant engineering environments. Based on an analysis of typical industrial process structures, the proposed architecture relocates geometric specification, manufacturability validation, and product–process coordination to early digital stages. Defined transition mechanisms between engineering, manufacturing, and assembly domains are introduced to prevent installation from functioning as a geometry-defining validation environment. The scientific contribution lies in the domain-specific operationalization of integration principles for tube fabrication through a governed process architecture that relocates geometric finalization to engineering, formalizes transitions between engineering and manufacturing, and institutionalizes manufacturing knowledge within digital design processes. The proposed process architecture comprises model-based tube system specification, manufacturing-oriented design validation, deterministic derivation and controlled release of fabrication data, digitally driven prefabrication, and structured geometric verification prior to assembly. In addition, technical and organizational boundary conditions, including data continuity, interface governance, and knowledge integration, are systematically addressed. The resulting framework provides a conceptual basis for reducing assembly-driven iteration, increasing reproducibility, and supporting the formalization of manufacturing knowledge in mechanical and plant engineering.