## 1 Introduction  
The product development process (PDP) is a well-known engineering activity that accompanies a new service or product from its conception to the market shelf. PDP involves steps such as drafting the concept, planning the overall design, accomplishing detailed design, and prototyping [1, 2]. While the first stages of the PDP consist of iterative steps enabling the designer to figure out conceptual solutions (idea generation), the last stages of the PDP are characterized by more practical activities with recursive tasks (engineering design). Computer-aided design (CAD) is considered the key tool of the embodiment design phase and, nowadays, the CAD tool combines the initial capabilities for which it was conceived (namely, to virtually create the part, display it in a 3D view environment, verify the consistency of the final assembly and quickly realize 2D engineering drawings) with the benefits deriving from the integration of the multidisciplinary design methodologies (e.g., environmental and ergonomic assessment) [3, 4]. Manufacturability describes the degree to which a product can be effectively manufactured, addressing both the overall feasibility and the excess cost [5]. Sharing the same objective, assembly is a manufacturing phase in which interchangeable parts/componentsare coupled in a sequential manner to create a semi-finished or an end product [6]. Design for manufacturing and assembly (DFMA) is a complex and multi-faceted engineering practice and allows the designer to predict manufacturability outcomes while designing a product [7]. DFMA comprises many tasks, including the identification of design features that make the manufacturing process unfeasible or too costly [8]. Within the context of manufacturing and assembly, welding plays a critical role. Welding is a joining process widely used in various industries, such as automotive, aeronautic, shipbuilding, oil and gas, and industrial/chemical plants. Design for welding (DFW) requires the definition of a list of design actions that are related to the geometry of the product under development and affect aspects of the overall product design such as (i) the type of welding, (ii) the material to weld, (iii) the geometry and the thickness of the weld plates, (iv) the geometry of the bevel, (v) the location of the weld beam, (vi) the dimensions for weld beam, (vii) the possibility to use intermittent versus continuous weld, and (viii) the accessibility for the weld gun and fixture equipment [9]. Moreover, many other activities are related to the welding process itself such as the settings of welding parameters (current and voltage), the consistency of joint design with approved standards, the levels of distortion in the base material, the selection of the wire/rod material and diameter, the number of passes, and the welding speed [10]. While the first set of actions refers to the product design and implication on subsequent welding operations, the second set of actions refers to welding engineering, which is characterized by different tasks that usually require ad hoc testing and qualification campaign, based on code requirements. On this aim, product designers often provide guidance on welding in design drawings and specifications in order to prevent misunderstandings and to emphasize code requirements, which are then validated by welding engineers with subsequent tasks. Thus, the design professional may intend to avoid past welding conflicts or errors, including welding information provided on their technical drawings. The geometrical modeling of components and the related welding beads in the definition of the final welded assembly requires avoiding the typical errors observed in past projects (negative knowledge) and to reinject the good practice (design guidelines) into the model under development.