Thread Quality Control in High-Speed Tapping Cycles

Thread quality control is becoming a widespread necessity in manufacturing to guarantee the geometry of the resulting screws on the workpiece due to the high industrial costs. Besides, the industrial inspection is manual provoking high rates of manufacturing delays. Therefore, the aim of this paper consists of developing a statistical quality control approach acquiring the data (torque signal) coming from the spindle drive for assessing thread quality using different coatings. The system shows a red light when the tap wear is critical before machining in unacceptable screw threads. Therefore, the application could reduce these high industrial costs because it can work self-governance.This research was funded by the vice‐counseling of technology, innovation and competitiveness of the Basque Government grant agreements IT‐2005/00201, ZL‐2019/00720 (HARDCRAFT project) and KK‐2019/00004 (PROCODA project)

Differential protein expression analysis of activated E2F2-/-T lymphocytes by means of label-free quantification method

Comunicaciones a congreso

Spiral Bevel Gears Face Roughness Prediction Produced by CNC End Milling Centers

The emergence of multitasking machines in the machine tool sector presents new opportunities for the machining of large size gears and short production series in these machines. However, the possibility of using standard tools in conventional machines for gears machining represents a technological challenge from the point of view of workpiece quality. Machining conditions in order to achieve both dimensional and surface quality requirements need to be determined. With these considerations in mind, computer numerical control (CNC) methods to provide useful tools for gear processing are studied. Thus, a model for the prediction of surface roughness obtained on the teeth surface of a machined spiral bevel gear in a multiprocess machine is presented. Machining strategies and optimal machining parameters were studied, and the roughness model is validated for 3 + 2 axes and 5 continuous axes machining strategies. Palabras claveThank you to the Department of Education, and to the Universities and Research program of the Basque Government for their financial support, by means of the ZABALDUZ program. We also thank the UFI in Mechanical Engineering department of the UPV/EHU for its support of this project

Meeting high precision requirements of additively manufactured components through hybrid manufacturing

A hybrid approach combining the laser powder bed fusion (LPBF) process and post-processing operations through 5-axis milling was employed to manufacture a Ti6Al4V aerospace component. From the design step, the requirements and needs in all the stages of the Hybrid Additive Manufacturing process were taken into account. A numerical simulation of distortions promoted by residual stresses during the additive process was employed to consider material allowance. The status of the as-built and post-processed component was analysed through scanning and CMM inspection and roughness measurements. The 3D scanned model of the as-built LPBF-ed component was used to understand the distortion behaviour of the component and compared to the numerical simulation. Finally, 5-axis milling operations were conducted in some critical surfaces in order to improve surface quality and dimensional accuracy of the as-built com- ponent. The inspection of the as-built and post-processed component showed the improvement achieved through the proposed hybrid approach. The work aims to provide the baselines needed to enable the metal Hybrid Additive Manufacturing of components with complex geometries where mandatory precision is required by integrating high accuracy machining operations as post-processing technique

Analysis of self-tapping screw joints in fibre glass reinforced PEI polymer used in the automotive industry

This article presents a study of the joining of polyetherimide (PEI) polymer parts reinforced with fibre glass which has great application in the automotive sector. A simulation model based on the finite element method is proposed. For the modelling of the polymeric material, the three-network viscoplastic (TNV) rheological model was used, with very adequate results and producing a good fit with the experimental data. In addition, a methodology is proposed that allows simplifying a three-dimensional to an axisymmetric model, which implies a notable reduction in computational cost. In addition, the work includes an experimental analysis that evaluates the tightening torque under conditions of assembly repetitiveness, relaxation over time and influence of thermal cycles. These scenarios have a different influence depending on the geometry of the self-tapping screw used. Regarding repetitiveness, it has been verified that PF-30 (CELOspArk (R)) loses 17.16% while in Delta-PT (DELTA PT (R)) it loses up to 41.93% in the tenth repetition. In contrast, in the relaxation over time scenario, the PF-30 loses 13.38% and the Delta-PT loses 17.82%. Finally, regarding the thermal cycles, cooling allows to slightly delay the loss of tightening torque in both screws in a similar way; however, in the heating stage, 36.89% is lost with PF-30 and only 14.66% with Delta-PT. This study represents an improvement in the knowledge of the joining processes of self-tapping screws with polymeric materials of an engineering nature. The simulation model can be easily adapted to other materials and other geometries, and the experimental study offers a vision of the evolution of tightening conditions in realistic operating scenarios

Meeting high precision requirements of additively manufactured components through hybrid manufacturing

A hybrid approach combining the laser powder bed fusion (LPBF) process and post-processing operations through 5-axis milling was employed to manufacture a Ti6Al4V aerospace component. From the design step, the requirements and needs in all the stages of the Hybrid Additive Manufacturing process were taken into account. A numerical simulation of distortions promoted by residual stresses during the additive process was employed to consider material allowance. The status of the as-built and post-processed component was analysed through scanning and CMM inspection and roughness measurements. The 3D scanned model of the as-built LPBF-ed component was used to understand the distortion behaviour of the component and compared to the numerical simulation. Finally, 5-axis milling operations were conducted in some critical surfaces in order to improve surface quality and dimensional accuracy of the as-built com-ponent. The inspection of the as-built and post-processed component showed the improvement achieved through the proposed hybrid approach. The work aims to provide the baselines needed to enable the metal Hybrid Additive Manufacturing of components with complex geometries where mandatory precision is required by integrating high accuracy machining operations as post-processing technique.(c) 2022 The Author(s). This is an open access article under the CC BY license (http://creativecommons.org/ licenses/by/4.0/)

Multi-Omics Integration Highlights the Role of Ubiquitination in CCl4-Induced Liver Fibrosis

Liver fibrosis is the excessive accumulation of extracellular matrix proteins that occurs in chronic liver disease. Ubiquitination is a post-translational modification that is crucial for a plethora of physiological processes. Even though the ubiquitin system has been implicated in several human diseases, the role of ubiquitination in liver fibrosis remains poorly understood. Here, multi-omics approaches were used to address this. Untargeted metabolomics showed that carbon tetrachloride (CCl4)-induced liver fibrosis promotes changes in the hepatic metabolome, specifically in glycerophospholipids and sphingolipids. Gene ontology analysis of public deposited gene array-based data and validation in our mouse model showed that the biological process “protein polyubiquitination” is enriched after CCl4-induced liver fibrosis. Finally, by using transgenic mice expressing biotinylated ubiquitin (bioUb mice), the ubiquitinated proteome was isolated and characterized by mass spectrometry in order to unravel the hepatic ubiquitinated proteome fingerprint in CCl4-induced liver fibrosis. Under these conditions, ubiquitination appears to be involved in the regulation of cell death and survival, cell function, lipid metabolism, and DNA repair. Finally, ubiquitination of proliferating cell nuclear antigen (PCNA) is induced during CCl4-induced liver fibrosis and associated with the DNA damage response (DDR). Overall, hepatic ubiquitome profiling can highlight new therapeutic targets for the clinical management of liver fibrosis.This work was supported by grants from Gobierno Vasco-Departamento de Salud 2013111114 (to M.L.M.-C.), ELKARTEK 2016, Departamento de Industria del Gobierno Vasco (to M.L.M.-C.), Ministerio de Ciencia, Innovación y Universidades MICINN: SAF2017-87301-R, SAF2017-88041-R, RTI2018-096759-A-100 and SAF2016-76898-P integrado en el Plan Estatal de Investigación Cientifica y Técnica y Innovación, cofinanciado con Fondos FEDER (to M.L.M.-C., J.M.M., T.C.D. and U.M. respectively); AECC Bizkaia (M.S.-M.); Asociación Española contra el Cáncer (T.C.D.), Fundación Científica de la Asociación Española Contra el Cancer (AECC Scientific Foundation) Rare Tumor Calls 2017 (to M.L.M., J.M.B., M.A.A., J.J.G.M.), La Caixa Foundation Program (to M.L.M.), 2018 BBVA Foundation Grants for Scientific Research Teams (to M.L.M.-C.). This research was also funded by the CIBERehd (EHD15PI05/2016) and “Fondo de Investigaciones Sanitarias, Instituto de Salud Carlos III”, Spain (PI16/00598 and PI19/00819, co-funded by European Regional Development Fund/European Social Fund, “Investing in your future”); Spanish Ministry of Economy, Industry and Competitiveness (SAF2016-75197-R); “Junta de Castilla y Leon” (SA063P17); AECC Scientific Foundation (2017/2020), Spain; “Centro Internacional sobre el Envejecimiento” (OLD-HEPAMARKER, 0348_CIE_6_E), Spain; University of Salamanca Foundation, Spain (PC-TCUE18-20_051), and Fundació Marato TV3 (Ref. 201916-31), Spain (to J.J.G.M.). The UPV/EHU Lab and the Proteomics Platform are members of Proteored, PRB3 and is supported by grant PT17/0019, of the PE I + D + i 2013-2016, funded by ISCIII and ERDF. Ciberehd_ISCIII_MINECO is funded by the Instituto de Salud Carlos III. We thank MINECO for the Severo Ochoa Excellence Accreditation to CIC bioGUNE (SEV-2016-0644)

Estudio de uniones embridadas para torres de generadores eólicos

Ingeniería IndustrialIndustria Ingeniaritz

Modelling and analysis of surface topography generated in face milling operations.

This paper presents a model for predicting the surface topography generated in face milling operations. In these operations, when the face mill inserts remove the workpiece material, they leave marks on the machined surfaces. The marks depend on the face mill geometry, the geometry and runout of the face mill inserts, and cutting conditions, e.g. feed and step over. In order to predict the surface topography, the geometry of the face mill cutting edges must first be modelled. The modelling of the cutting edge geometry is for round insert face mills and for square shoulder face mills. Due to the influence of insert runout on the final surface topography, axial and radial runouts of the face mill inserts are also taken into account in the modelling of the cutting edge geometry. Next, the equations expressing the trajectory of any cutting edge point are derived as a function of the feed value, the rotation angle of the face mill, its axial position, and its radial position with respect to the face mill axis. Finally, given the cutting edge geometry and the trajectory of cutting edge points, a methodology based on the discretization of the milled surface in a grid with a finite number of points is developed in this paper for the simulation of the surface topography. The methodology is based on the fact that at each grid point, the final height of the topography will be the height of the workpiece material remaining at this point after many face mill revolutions. For this reason, the procedure initially estimates the rotation angles of the face mill for which the face mill cutting edges in their front-cutting and back-cutting motion pass by the grid point being considered. In order to achieve this, a transcendental equation that is only dependent on the rotation angle is derived from the cutting edge trajectory equations. This equation is transformed into an equivalent polynomial equation by means of Chebyshev expansions. The transformed equation is solved for the rotation angle using a standard root finder that does not require a starting value. Then, by means of the estimated rotation angles and the cutting edge trajectory equations, the radial positions of the cutting edge points passing by the grid point are obtained. Finally, based on these radial positions and the cutting edge geometry, the heights of cutting edge points, which can generate the surface topography at this grid point, are estimated. The final height of the surface topography will correspond to the lowest value among the estimated height values. The methodology can be easily extended and applied to face mills with other insert geometries or to face mills with central and peripheral inserts. In addition, the simulation of the surface topography generated by lateral passes in face milling operations is simplified. The procedure allows the influence of the face mill geometry, the feed value and the step over between passes to be analysed and the roughness values to be predicted. In order to validate the model predictions, a series of face milling tests are carried out. Predicted surface topographies are compared with measured topographies and a good agreement between them is observed