Evaluation of near-dry machining effects on gear milling process efficiency

One of the main environmental pollution sources related to machine building industry is the huge amount of cutting fluids which are supplied during the machining processes. In order to avoid the problems induced by cutting fluids' usage, considerable progress has been recently made in the field of near-dry machining (NDM). Converting conventional processes to minimal quantity lubrication (MQL) methods imposes new tasks' classification within the tribiological system in order to guarantee the process safety and product quality. This paper gives an overview on some requirements to be considered for a successful MQL application into industrial practice. Its last part is focused on the evaluation of NDM effects on the gear milling process efficiency, with respect to hob wear, surface quality, cooling effect, and environment protection.     

Application of Taguchi method to selection of optimal lubrication and cutting conditions in face milling of AlMg3

This paper outlines the Taguchi optimization methodology, which is applied to optimize the cutting parameters in face milling when machining AlMg₃ (EN AW 5754) with HSS (high speed steel) tool under semi-finishing conditions in order to get the best surface roughness and the minimum power consumption. Beside the conventional flood lubrication, the investigations include the minimal quantity lubrication and the dry milling. These environment-friendly cutting techniques are considered two practical ways to the cleaner manufacturing in the context of the sustainable production. The parameters evaluated are the cutting speed, the depth of cut, the feed rate and the cooling lubrication techniques (cutting fluid flow). The appropriate orthogonal array, signal to noise (S/N) ratio and Pareto analysis of variance (ANOVA) are employed to analyze the effect of the mentioned parameters on the good surface finish (surface roughness). This paper illustrates the application of the techniques for single performance characteristics optimization, which employs the weighting factors to each of the S/N ration of the responses to obtain a multi-response S/N ratio for each trial of the orthogonal array and, finally, a single optimal process parameters setting. Using Taguchi method for the design of experiments (DOE), it is investigated the significant influence and the parameters interaction effect with minimum number of trials as compared with a full factorial design.     

Macro-level environmental comparison of near-dry machining and flood machining

This paper focuses on investigating several aspects of the machining process from an ecological perspective, the result being a macro-level analysis. The analysis presented here considers not only the environmental impact of the material removal process itself, but also the impact of the associated processes such as the material preparation, and the scrap processing. A macro-level assessment of the comparative life cycle environmental performance of the near-dry machining (NDM) using TiN-coated carbide tools and the flood machining (FM) is performed by a case study referring to the gear milling. The assessment, using the SimaPro 7.1.5 software and the ecoinvent1.5 database, includes combined Life Cycle Assessment (LCA) of the workpiece material, the scrap processing, the use of lubrication, and the energy consumption.