Portability study of Surface roughness models in milling

[EN] In spite of the huge number of research studies around empirical surface roughness models, there is no methodology applied in industry to model and adapt accurately the surface roughness in machining operations. Any change of the process with respect to the initial conditions where the experiments were conducted implies an additional estimation error which difficulties the use of the model in the current process. This paper studies the portability of empirical models for surface roughness prediction in face milling operations. As portability problem, we refer to how a proper surface roughness model obtained from theoretical/experimental data under specific conditions decreases its performance when it is applied in a different environment. The work gives some guidance for future design of more robust surface roughness models.Abellán-Nebot, J.; Bruscas, G.; Serrano, J.; Vila, C. (2017). Portability study of Surface roughness models in milling. Procedia Manufacturing. 13:593-600. doi:10.1016/j.promfg.2017.09.115S5936001

Fostering in-process inspection during process planning using tolerance charting

ntegrated development of machining and inspection plans is essential in dynamic manufacturing environments, especially when right first time manufacturing is required. In this work, a methodology, based on a new and extended use of tolerance charting, that allows incorporation of in-process inspection operations to improve process plans is presented. The methodology proposes the transfer of the manufacturing specification toleranc e between surfaces to specific ation tolerances established between these surfaces and a common reference system. In this way, all variability sources originated by part locating and fixturing can be separately considered from the ones originated by the process-machine system. This circumstance allows a more accurate calculation of operation capability indexes and eases the analysis and improvement of critical operations. To prove methodology potential, an application case is showed.Bruscas Bellido, G.; Romero Subiron, F.; Rosado Castellano, P.; Serrano, J. (2013). Fostering in-process inspection during process planning using tolerance charting. Procedia Engineering. 63:200-207. doi:10.1016/j.proeng.2013.08.175S2002076

Economical and technological study of surface grinding versus face milling in hardened AISI D3 steel machining operations

[EN] This work deals with the technological and economic considerations required to select face milling vs. surface grinding operations in the manufacture of hardened steel flat surfaces for dies and moulds. In terms of technological considerations, factors such as component geometry, material and surface quality (dimensional tolerance and surface finish) are taken into account. The economic considerations include the cost of machine depreciation, labour and consumables (cutting tools in face milling vs. grinding wheels and dressing tool in surface grinding). A case study is presented based on the prismatic components in ceramic tile moulds and their associated manufacturing operations. Surface grinding and face milling experimentation was conducted on cold work steel AISI D3 (with hardness of 60 HRC) with aluminium oxide grinding wheels and coated tungsten carbide cutting tool, respectively. Technological attributes and economics of face milling are compared with surface grinding of this type of mould components. The main conclusion is that face milling with chamfered edge preparation in coated tungsten carbide tools is a competitive process, compared with surface grinding, in terms of product quality and economics.The research team would like to acknowledge the main support of the Caja Castello-Bancaixa Foundation and Universitat Jaume I, which support the project: "Integration of Planning, Execution and Control of High Speed Machining Operations in Collaborative Engineering Environments: Application in Moulds for Tile Industry", the ceramic tile mould company MACER S.L., and would like to extend their gratitude to Roberto Menendez, student of industrial engineering. Particular thanks go to the Programme Alssan: European Union Programme of High Level Scholarships for Latin America (scholarship no. E04D030982MX). Additional support was provided by Tecnologico de Monterrey through the research group in Mechatronics and Intelligent Machines (http://cidyt.mty.itesm/cimec).Vila Pastor, C.; Siller, H.; Rodríguez, C.; Bruscas Bellido, G.; Serrano, J. (2012). Economical and technological study of surface grinding versus face milling in hardened AISI D3 steel machining operations. International Journal of Production Economics. 138(2):273-283. doi:10.1016/j.ijpe.2012.03.028S273283138