Our researchers

Miguel Arizmendi Jaca

Most recent scientific publications (since 2010)

Authors: Arizmendi, Miguel; Cumbicus, Wilmer Euclides;
Journal: INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
ISSN 0268-3768  Vol. 96  2018  pp. 1971 - 1990
A model that predicts the appearance of low-frequency lateral vibrations in drilling with pilot hole is proposed in this work. These vibrations, called whirling in the literature, are responsible for the generation of lobe-shaped holes during drilling. The present model considers both the influence of the regenerative effect of vibrations on the cutting forces and the influence of the process damping phenomenon that appears along the main cutting edges. In order to model cutting forces, cutting edges are divided into discrete elements and for each of them oblique cutting model is employed. Specific cutting forces at each cutting edge element are calculated as function of cutting speed and normal rake angle value. A new methodology is developed to analyze the motion equation of the drill in the frequency domain in order to predict the appearance of whirling vibrations during drilling with pilot hole. Regarding the depth of cut and the spindle rotational speed, drilling stability limits against low-frequency lateral vibrations are obtained. Moreover, in the presence of vibrations, the model can predict the whirling frequencies that are excited depending on the established cutting conditions. In addition, the stability model is experimentally validated via drilling tests over pilot holes of different diameters for a wide range of cutting conditions. In order to study the appearance of low-frequency vibrations and to avoid the appearance of other vibrations such as regenerative chatter, the analysis is focused on low spindle speed values. A comparison between predicted vibration frequencies and actual frequencies in measured cutting forces during drilling tests is carried out and a good correlation between them is observed.
Authors: Estrems, M; Cumbicus, Wilmer Euclides; Zabaleta, A.J.; et al.
Journal: INTERNATIONAL JOURNAL OF MECHATRONICS AND MANUFACTURING SYSTEMS
ISSN 1753-1039  Vol. 10  Nº 2  2017  pp. 101 - 114
The geometric tolerances of cylindrical workpieces are highly influenced by clamping forces. This relation is of special importance in slender workpieces such as thin rings. Better tolerances are achieved with lower clamping forces, but the disadvantage is that friction is reduced and the risk of slipping increases. Thus, in order to control the process, a key factor is achieving the lowest possible clamping force while still ensuring safety. Cylindrical parts are usually machined in lathes that have concentric plate chucks that are fixed either mechanically with wrenches or hydraulically by controlling pressure with valves. This paper proposes a method for measuring clamping forces in lathes during the turning process. The method allows the clamping force to be calculated from the torque applied by a dynamometric wrench or from valve controlled hydraulic pressure.
Authors: Diéguez, P.M.; Arizmendi, Miguel; et al.
Journal: PROCEDIA ENGINEERING
ISSN 1877-7058  Vol. 132  2015  pp. 190 - 196
Tapping by cutting is one of the most common operations in manufacturing. This multi-teeth tool, known as a tap, cuts the thread in a hole when the piece has a high added value. The thread quality is ensured when the tap is new or slightly worn, yet when tap wear is high; the quality of profiles exceeds tolerance limits and therefore a defect occurs in the manufacturing line. The aim of this paper is to study the tap wear of titanium nitride coated taps measured on nodular cast iron. The level of tap wear is determined by optical images and the wear mechanics are classified by scanning images and energy dispersion spectroscopy analysis. The results highlight that the critical part in measured taps is between the last chamfer and the first cylinder teeth and, consequently, the thread profile is under-sized. Beside adhesive wear, coating removal and chipping are the main wear aspects during tapping operations
Authors: Estrems, M.; Arizmendi, Miguel; Zabaleta, A.J.; et al.
Journal: PROCEDIA ENGINEERING
ISSN 1877-7058  Vol. 132  2015  pp. 872 - 879
This paper presents a model to estimate the total deformation of turned rings. It takes into account the clamping forces values at different angular positions of the workpiece, and the cutting forces during machining. The model is based on the Castigliano Theorem and uses the Chebyshev polynomials to get a stable solution to the differential equation of deformation. Cutting tests were conducted in a lathe and resultant roundness profiles were measured. The results showed good agreement with the model predictions
Authors: Estrems, M.; Arizmendi, Miguel; Cumbicus, Wilmer Euclides; et al.
Journal: PROCEDIA ENGINEERING
ISSN 1877-7058  Vol. 132  2015  pp. 456 - 463
Measuring the clamping forces on cylindrical workpieces is a key factor in the geometrical tolerances of such components, especially if they are slender as the case of thin rings. The lower the clamping force, better tolerances will be achieved, but with the disadvantage of reducing friction and, therefore, increasing the risk of slipping. Therefore, achieving a minimum but safe clamping force is a key factor to control the process. Usually, these parts are made in lathes that have concentric plate clutches and these are fixed mechanically by wrenches or hydraulically through the control of pressure by valves. A simple and economic method is proposed to measure the clamping forces in lathes, although it is necessary the use of a model for the ring deformation. This method allows knowing the clamping force from the torque applied by a dynamometric wrench, or from the hydraulic pressure controlled by valves.
Authors: Arizmendi, Miguel; et al.
Journal: PROCEDIA ENGINEERING
ISSN 1877-7058  Vol. 63  2013  pp. 208 - 217
Tapping by cutting is one of the most common operations in manufacturing. It consists of cutting internal threads on the wall of a previously drilled hole by means of a tool called a tap that has cutting edges on its chamfered periphery. When taps are new or slightly worn the process is usually in control and the geometry of the resulting threads on the work piece is correct. But as the tap wear increases the thread geometry deviates progressively from the correct one and eventually the screw threads become unacceptable. The aim of this paper consists on an industrial monitoring application (SPC) to data coming from the current signal of the tap spindle for assessing thread quality. It operates on line and indicates when the tap wear is so critical that, if the process were continued, it would result in unacceptable screw threads. Then the system shows a red light so that the operator could replace the worn-out tap. The system would be very cost-effective since the tapping process could be run without any operator intervention
Authors: del Castillo, E.; et al.
Journal: INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
ISSN 0268-3768  Vol. 69  Nº 42587  2013  pp. 1273 - 1282
Tapping is a widely employed but complex manufacturing process in which a multi-toothed tool, known as a tap, cuts a mating thread when driven into a hole. In this paper, the experiments, statistical analysis and the on-line implementation of a new thread quality monitoring system are presented for a tapping process in high-speed conditions. A multivariate statistical process control chart, for each tap, is presented based on the principal components of the torque directly measured from spindle motor drive. The on-line implementation of the multivariate chart provides tap wear warnings and alarms before the process starts producing unacceptable screw threads. The system is cost-effective since the tapping process can be run automatically without any operator intervention, does not require intrusive sensors, does not result in false negatives (defects) and provides an acceptable number of false positives.
Authors: Aristizabal, M.; Ardila, L.C.; et al.
Journal: WEAR
ISSN 0043-1648  Vol. 280-281  2012  pp. 15 - 21
A tribological test has been designed for analysing the wear behaviour of WC¿Co and WC¿Ni¿Co¿Cr alloys in contact with steel at high temperatures (725¿775 °C) and pressures (between 113 and 134 MPa). The test, based on a particular block-on-ring configuration, allows to measure wear and friction occurring between a cemented carbide sample and a steel wheel rotating at high speed in absence of lubrication. In general, wear resistance increases with hardness, which, keeping constant the WC grain size, depends mainly on the metallic content of the alloy. Thus, cemented carbides with 15 wt.% of metallic content exhibit lower mass losses than those with 25 wt.% of metal. Nevertheless, when compositions with the same metallic content are compared, it is confirmed that the wear resistance is similar for the compositions based on Ni¿Co¿Cr binders in spite of their lower hardness. This is likely due to the higher oxidation resistance of these alloys compared to those based on cobalt. Friction coefficients are lower for the compositions with higher metallic content, what is likely due to the formation of continuous oxide tribofilms with lubricant properties. Highlights ¿ This work compares the wear resistance of WC¿Ni¿Co¿Cr and WC¿Co alloys in contact with steel at high temperature. ¿ For the same metal content, WC¿Ni¿Co¿Cr alloys present higher wear resistance than those based on WC¿Co, in spite of their lower hardness. ¿ This abnormal behaviour is related to the highe
Authors: Arizmendi, Miguel; et al.
Journal: INTERNATIONAL JOURNAL OF MACHINE TOOLS AND MANUFACTURE
ISSN 0890-6955  Vol. 50  Nº 1  2010  pp. 51 - 64
This paper presents a model for the prediction of heterogeneity bands in the topography of surfaces machined by peripheral milling accounting for tool runout. Ideally, when the tool is clamped in the toolholder, all the cutting edges of the tool are located at a distance equal to the tool nominal radius from the rotational spindle. However, tool runout causes each cutting edge to be at a different radius from the spindle axis and this affects the topography of the milled surfaces. The proposed model includes the effects of two factors that produce tool runout: tool setting error and cutter grinding errors (CGE). The influence of tool setting error on the surface topography in peripheral milling has been widely modelled in the literature in the past but the contribution of CGE has not been investigated so far because these errors were relatively smaller. With the increasing precision of toolholders, the magnitude of both errors is similar and therefore, the influence of CGE on the surface topography can no longer be neglected. In this paper, an expression for the effective radius of the cutting edges taking into account tool setting error and CGE is first derived. Next, a model for the prediction of heterogeneity bands is presented. A detailed study of band formation was carried out that makes it possible to study the influence of tool runout and feed on the band geometry (position and width) and on the roughness variations along the milled Surface. Finally, cutting tests were conducted in order to validate the proposed model by comparing the experimental results with the predicted ones and a good agreement between them was found. (C) 2009 Elsevier Ltd. All rights reserved.
Authors: Arizmendi, Miguel; et al.
Journal: INTERNATIONAL JOURNAL OF MACHINE TOOLS AND MANUFACTURE
ISSN 0890-6955  Vol. 50  Nº 12  2010  pp. 1097 - 1114
A method for the identification of the tool parallel axis offset (TPAO) that occurs when the end mill is held in the spindle is developed. The method is based on the analysis of the topography of surfaces machined by peripheral milling and considers the cutter grinding errors. As known from the literature, TPAO causes each cutting edge to be at a different radius from the spindle axis and creates transition bands in the topography of milled surfaces, in which roughness grooves generated by different teeth blend together. In this paper, the TPAO, defined by the distance of the tool axis from the spindle axis and by an angle relating the offset direction to the position of cutting edges, is expressed as a function of the width of the roughness grooves at any height of the transition bands. This expression allows the TPAO to be estimated by measuring the groove widths at only two heights and solving a system of two linear equations. In order to obtain the groove widths, a procedure based on digital image processing is developed. Through this procedure, the groove widths are estimated at more than the two necessary heights without high computational cost. This leads to the resolution of an overdetermined system of linear equations that allows the TPAO to be identified with more accuracy. Finally in order to verify the predictions of the proposed method, a series of cutting tests were carried out. A reasonable agreement between the experimental results and the predicted ones was found. (C) 2010 Elsevier Ltd. All rights reserved.