Experimental study of machining system: dynamic characterization (original) (raw)
Related papers
Dynamic characterization of machining systems
The International Journal of Advanced Manufacturing Technology, 2011
In the working space model of machining, an experimental procedure is implemented to determine the elastic behaviour of the machining system. In this paper, a dynamic characterization and vibration analysis has long been used for the detection and identification of the machine tool condition. The natural frequencies of the lathe machining system are required (Ernault HN400 -France) according to three different situations with no cutting process are acquired. The system modal analysis is used to identify the natural frequencies. These frequencies are then compared to the ones obtained on the spindle numerical model by Finite Element Method. This work is validated by experimental tests based on measures of the lathe machine tool frequencies domain. The main objective is to identify a procedure giving the natural frequencies values for the machine tool components, in order to establish a better condition in the cutting process of the machine tool.
TJPRC, 2013
In this paper the chatter vibrations in metal cuttings on lathe machine is investigated experimentally. Since the dynamic cutting force is strongly influenced by the variations of cutting parameters, the objective of present paper is to consider the variations of cutting speed, feed and depth of cut on the vibrations of cutting process on the lathe machine, By analyzing experimental results it can be concluded that maintaining appropriate cutting parameter play important role in suppressing vibration that are developed during metal cutting process. For each of cutting conditions, the variations of cutting force component (thrust force) as a function of time are obtained numerically and treated as the input excitation for the lathe machine. The measurement of vibration in terms of acceleration by accelerometer is expressed as a function of time.
Experimental Study of the Static Modal Analysis on Milling Machine Tool
Advanced Materials Research, 2014
Machine tool vibrations have great impact on machining process. Modal testing is a form of vibration testing which is able to determine the Frequency Response Function (FRF) of the mechanical test structures. In this paper, the main focus is to identify a procedure to obtain natural frequency values for machine tool components in order to establish better conditions in the cutting process on the machine tool. For this purpose, a 3D model of the machine tools structure is made using design software and exported to analysis software. Later on, the Finite Element Method (FEM) modal analysis was used to obtain the natural frequencies. The model is evaluated and corrected through an experimental modal test. In the experiment, the machine tool vibration is excited by impact hammer and the response of excited vibration is recorded. In the end, the result of both FEM and experimental shows a good consistency in comparison.
Frequency Analysis of the Tool with and without Wear during Turning by Modal Analysis
Journal of Material Sciences & Engineering, 2018
The stability of a cutting process directly influences the quality of a final surface. The control of the cutting process is an important problem for machining technology. Instabilities usually manifest as harmful chatter vibrations generated during cutting. Modal testing is a form of vibration testing which is able to determine the Frequency Response Function (FRF) of the mechanical test structures. In this context, we realized a study of vibration and of deformation between a tool without defect and a tool with two cases of defects. These defects have a random shape (any form), and the contact length tool-work piece, is considered the length of defects Lc=1 mm and the height of wear has been studied for two cases: VB=0.1 and 0.2 mm. In this paper, the main focus is creating a predictive model based on vibrations of body mass. The body mass mean the amount of material that constituting the cutting tool. The loss of a part of this mass makes the tool lighter; it increases the vibration of the tool. In addition to that, the Finite Element Method (FEM) modal analysis was used to obtain the natural frequencies. In this analysis we use ANSYS software based on (FEM), it is known for its high performance, quality and ability to solve all kinds of challenging simulations. The main idea is to create defects (wear) on the flank surface in order to create a model prediction. After the creation of defects, we start the modal analysis to study the deformation and the frequency of the tool.
New method to characterize a machining system: application in turning
International Journal of Material Forming, 2009
Many studies simulates the machining process by using a single degree of freedom spring-mass system to model the tool stiffness, or the workpiece stiffness, or the unit tool-workpiece stiffness in modelings 2D. Others impose the tool action, or use more or less complex modelings of the efforts applied by the tool taking account the tool geometry. Thus, all these models remain two-dimensional or sometimes partially three-dimensional. This paper aims at developing an experimental method allowing to determine accurately the real three-dimensional behaviour of a machining system (machine tool, cutting tool, tool-holder and associated system of force metrology six-component dynamometer). In the work-space model of machining, a new experimental procedure is implemented to determine the machining system elastic behaviour. An
A Review Paper on Vibration Monitoring of Lathe
IJSRD, 2014
In any machining operation vibration is frequently problem,The vibration signatures for different arrangement are recorded to determine the dynamic characteristics of the system,. These vibration signatures are analyzed to determine causes of inaccuracy in the manufacturing process and faulty components. Many condition monitoring techniques are available to monitor the machine experimentally. Among these techniques vibration monitoring is the most widely used technique because most of the failures in the machine tool could be due to increased vibration level. Experimental vibration analyses are conducted for a lathe system to detect the possibility of faults and to develop accurate cutting process. Experiments are carried out using the condition monitoring instrument Accelerometer to measure vibration severity for different cutting speed, depth of cut, feed rate for different work piece material.
TOOL FOR RESEARCHING THE DYNAMIC SYSTEM OF METAL-CUTTING MACHINE
2018
Dynamic characteristics of the system flexibility of the machine affect the accuracy of machining, so the study of this problem is very important. Fluctuations of the machine elements significantly affect the error of the shape of the workpiece. The quality of the processing is determined not so much by the static displacements between the tool and the workpiece but the stability of the machine system as a whole. There are many solutions of vibroacoustic diagnostics devices for machines and machine-tools in the related publications. Defects in the spectrum of vibroacustic signals are found in the process of manufacturing and assembling machines in the form of discrete components, parameters of which are used in vibroacoustic diagnostics as informative diagnostic features. Along with that there is, but not so common, another type of dynamic system analysis of the machine, which can be carried out by experimental methods, or, in particular, by simulating the perturbation of a dynamic system by cutting forces of special type. Imitated disturbance is carried out by using a tool of a special form. During the processing cutting edges of the tool create a pseudorandom process with certain statistical characteristics, in particular, the correlation function. The proposed design of the tool makes it possible to perform the research of frequency parameters of the dynamic system of the machine without complex loading devices.
VIBRATION MEASUREMENT ON CUTTING TOOL UNDER VARIOUS OPERATING CUTTING PARAMETERS
IAEME Publication, 2021
Machining and measuring operations are invariably accompanied by relative vibration between work piece and tool. The effect of vibration is excessive stresses, undesirable noise, looseness of part and partial or complete failure of parts. In this work the cutting tool vibration will be measured by using digital Vibrometer, which can measure displacement velocity, acceleration and frequency. The sensor will be attached with the tool post for sensing the vibration tool during turning operation. Vibration also increases in the cutting tool due to whiling of the job mounted between two stocks of lathe machine. With the increasing feed rate, the surface roughness of work will increase. The feed rate can be considered as a main cutting factor in the machining operation. The mildsteel material will be used for collecting data at various cutting parameters like depth of cut, speed, feed rate etc. on the completion of experimental work data will be analysing using MATLAB. By doing the same we will be able to predict behaviour for the system under any operating cutting parameters.
Prediction and control of Lathe Machine tool vibration – A Review
The present work concentrates and aims on study of different controllable parameter that affects the responses like vibration amplitude. The prediction of vibration between the tool and work piece is important as guideline to the machine tools user for an optimal selection of depth of cut and rotation of spindle to minimize the vibration.Machining is a complex process in which different parameters can deleterious the desired result. Among them, cutting tool vibration is an important which influences dimensional precision of components machined, life of the cutting tool is very important. Cutting tool vibration are mainly produced cutting parameters like cutting speed, depth of cut and tool feed rate. In this work, the cutting tool vibrations are controlled in lathe machine where the tool holder is supported with and without damping pad. The cutting tool vibration signals were controlled through FFT analyzer. To predict and validate result by using Taguchi method, Experimental studies and data analysis have been performed to validate the proposed damping system. By using regression analysis best suitable equation is developed to predict the probable value response for given predictor value.