Study and comparison of the different costs’ schema associated to geometry, material and processing between 3D printing, injection molding and machining manufacturing technologies

Abstract

Cost models to assess and compare the level of expenditure incurred when manufacturing a part by applying different production technologies are of big importance for industrial companies. However, the more precise a cost model is, the more information is needed in order to complete the costs calculation; thus, rising an emergent need for simplified yet accurate enough cost models. Building on a real industrial case study from a company dedicated to the supply of spare parts, the present paper starts proposing a categorisation of products capable of describing the level of added value of a part -being considered as high, average or low. Also, the paper proposes a simplified mathematical model for calculating and comparing parts costing, considering some estimators for geometry, material use and process complexity in the part. The model is applicable to calculate the production costs of a part made via additive manufacturing, injection molding and machining technology. Considering that other product-associated cost factors (such as logistic costs, warehousing, etc.) remain constant, the model can be utilized to compare the different production options and to advise which one would be more cost-effective to be applied. Finally, the cost models are applied to four products of high or average added value from the industrial company analyzed. In this application, the models reveal an acceptable level of cost approximation only in the cases of additive and subtractive manufacturing technologies.