minimum of 5,000 kg to 23,000 kg of zinc material is required. The die-set cost is 40~ 60 million won.
In addition, the correlation between the batch size and the cost for part production using stamping process is graphically shown. Since the 3D printing excavator cabin production cost is about $2,500 excluding the labor cost, it is more economical than the existing stamping process as long as the batch size is under 50 [26] (Figure 44). Figure 45 compares the important conventional manufacturing process and the additive manufacturing process. Through this project, The AM process can be connected to the assembly process via a simple machining process after direct parts fabrication. Therefore, there is no need for a stamping process to make the shape of the product, and the process of designing and manufacturing the Jig and Fixture is also optional. In conclusion, the stamping process is replaced with direct parts fabrication to create the most internal and external parts that make up the cabin, resulting in cost savings and reduced time required for development.
Figure 44 The correlation between the batch size and the cost process using the stamping process and LOAM
Figure 45 Comparison process between Conventional process and Additive Manufacturing
Conclusion
Over the past decade, the Additive Manufacturing field has seen significantly growth and new technology emerging. At present, additive manufacturing technology is not only affect in prototype manufacturing, but also successful examples of final product manufacturing are pouring out. It becomes possible to freedom from the constraints of conventional manufacturing process method and to realize the more advanced design as the feasibility becomes higher. However, there are still negative views that additive manufacturing is difficult to apply to industry. Obviously, the development of AM technology has made it possible to implement high-resolution surface smoothness, correct dimensional accuracy, and high mechanical properties as final products. However, over the decades, AM has not been aware of the ultimate problems in real industry as AM develops within its own constraints. The fact that AM process is not a big advantage for the size and production of various products made in real industry.
However, new methods of additive manufacturing are attracting attention in order to offer solutions from the point of view of real industry. Large Object Additive Manufacturing not only allows the size of large structures to be created, but also has the advantage that build-up speed is much higher than other Additive manufacturing processes. Therefore, in this study, Excavator cabin applying Design for Additive Manufacturing (DfAM) which make full use of advantages of AM capabilities was made using LOAM. The ultimate goal of this study is to demonstrate the applicability of the AM process to the fabrication of large structures by manufacturing the excavator cabin using the AM process.
characteristics and specifications of real cabin were considered and redesigned as a part for 3D printing by applying DfAM, and Physical printing was performed using LOAM which can rapidly fabricate large structure. At the same time, AM’s direct fabrication can save considerable time and cost by replacing the main process required for cabin manufacturing.
This study can be used as a methodology when creating final products through new project, product development, using 3D printing technology, etc. In order to make a 3D printed product by applying DfAM, it is necessary to understand precisely characteristics and purpose of the object to be created.
This allows selection and application of appropriate design techniques in the design process. For real production, AM process selection is needed considering object characteristics and purpose. In order to choose a proper AM process selection, the characteristics and limitations of AM to be used should be considered. After AM process selection, identify the elements that interfere with the actual production and completion, or take into account the new requested parts of the client or designer, and the process should be proceed of mutual correction through feedback to finalize the final design. Once the final
design has been decided, begin actual production. At the same time, assembly and post-processing are discussed and combined with the conventional process. Figure 46 is shown the process flow for production of 3D printed products using DfAM.
The use of LOAM allows rapid prototyping of large-sized structure and the limitations of AM technology in real industry will no longer be a problem. Over time, LOAM’s technology development will produce larger, higher quality products. However, the technical limitations of LOAM need to be supplemented. It is necessary to improve the limited design complexity as generating supporter from the present situation in which the non-supporter shape must be maintained. In order to produce smooth parts, need improved toolpath generator of slicing software. Further research is needed. LOAM has a rougher surface quality than other AM processes, making post-process is very difficult. In order to solve rough surface quality, it is necessary to discuss a combining system with conventional processes.
Therefore, we will study the development of product quality by using a system combining LOAM and conventional process as a future work.
Figure 46 DfAM process for Large Object Additive Manufacturing
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