Especially in manufacturing processes of welded assemblies made of sheet metal, a large number of individual parts can act as a significant cost driver. Low quantities and a variety of sheet thicknesses of the individual parts within a welded assembly result in avoidable costs due to programming and setup efforts. However, many welded parts can be decisively optimized or replaced with the help of well-thought-out sheet metal bending designs.
Cost-intensive manufacturing step ‘welding’ - avoid or optimize.
Welding processes play a major role in pricing. Suppliers usually still manually adapt customer data to the requirements of their production in order to increase their process reliability and minimize their own effort. Depending on the customer's specifications, each individual weld may require complex subsequent work steps. Geometric conditions can also preclude automated production and make manual welding indispensable. Far from automated high-volume production, manual straightening and grinding efforts represent significant cost drivers in addition to the joining process.
Although welding processes cannot be completely prevented in many applications, time can be saved within the production process by using alternative methods, such as manual or automated spot welding. In combination with the previously mentioned optimizations, downstream machining processes can be reduced.
Minimize number of parts and material thickness.
Assemblies whose core consists of a combination of tubes of any kind and laser parts can be replaced by one-piece sheet metal bending designs. The integrated design of gusset plates as legs or the use of cross bends, so-called ‘crowning’, can reduce the number of parts and the required material thickness.
Furthermore, the designer is not bound to the dimensions of standardized semi-finished products, which can account for a considerable proportion of the material costs depending on how common their dimensions are.
Design guidelines can ensure that welded assemblies cannot be replaced by cost-effective one-piece sheet metal bending designs. However, restrictions of this type do not mean that optimization potential cannot be found with regard to the number of parts. If several assembly positions have the same raw material thickness, they can be integrated into the main part using webs as predetermined breaking points. This can be done by positioning them within larger inner contours, the so-called ‘burnout’. This procedure ensures that the material already calculated in the blank can be used for further parts and only increases the laser time of the individual part.
Integration of reinforcements and gussets.
Furthermore, reinforcements and gussets can be part of the actual sheet metal bending part. For this purpose, legs can be designed as inner contours and contribute to the stability of the overall part by means of bending and short welds.
Externally sourced parts in particular often have unused potential for optimization, since possible design changes with a view to optimization entail design optimization for the supplier and internal coordination processes for the customer. However, if a part is optimally matched to the production of a supplier, this circumstance limits the number of cost-effective alternatives in the event of delivery bottlenecks and failures. Thus, a well-thought-out design still forms the foundation of a cost-effective manufacturing process.