Suppression of Regenerative Chatter in a Plunge-Grinding Process by Spindle Speed

This paper utilizes an effective control strategy to suppress the regenerative chatter in a plunge-grinding process. To begin with, the dynamical interaction between the workpiece and the grinding wheel is considered as a major factor influencing the grinding stability. Mathematically, the grinding stability is studied through numerical eigenvalue analysis. Consequently, critical chatter boundaries are obtained to distinguish the chatter-free and the chatter regions. As known, the grinding is unstable and the chatter happens in the chatter region. To observe the chatter vibrations, an analytical method and numerical simulations are employed. As a result, chatter vibrations both with and without losing contact between the workpiece and the wheel are obtained. Meanwhile, the coexistence of the chatter and the stable grinding is also found in the chatter-free region. Finally, a control strategy involving spindle speed variation (SSV) is introduced to suppress the chatter. Then, its effectiveness is analytically investigated in terms of the method of multiple scales (MMS).

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A dynamic model of cylindrical plunge grinding process for chatter phenomena investigation

MATEC Web of Conferences ◽

10.1051/matecconf/201814809004 ◽

2018 ◽

Vol 148 ◽

pp. 09004

Author(s):

Paweł Lajmert ◽

Małgorzata Sikora ◽

Dariusz Ostrowski

Keyword(s):

Degrees Of Freedom ◽

Stability Limit ◽

Element Model ◽

Grinding Wheel ◽

Grinding Process ◽

Plunge Grinding ◽

Chatter Vibrations ◽

Grinding Conditions ◽

The Stability ◽

Improved Model

In the paper, chatter vibrations in the cylindrical plunge grinding process are investigated. An improved model of the grinding process was developed which is able to simulate self-excited vibrations due to a regenerative effect on the workpiece and the grinding wheel surface. The model includes a finite-element model of the workpiece, two degrees of freedom model of the grinding wheel headstock and a model of wheel-workpiece geometrical interferences. The model allows to studying the influence of different factors, i.e. workpiece and machine parameters as well as grinding conditions on the stability limit and a chatter vibration growth rate. At the end, simulation results are shown and compared with exemplified real grinding results.

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Suppressing Chatter in a Plunge Grinding Process: Application of Variable Rotational Speed of Workpiece

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.249-250.259 ◽

2012 ◽

Vol 249-250 ◽

pp. 259-262

Author(s):

Yao Yan ◽

Jian Xu

Keyword(s):

Contact Force ◽

Control Strategy ◽

Rotational Speed ◽

Grinding Process ◽

Chatter Vibration ◽

Plunge Grinding ◽

System Parameters ◽

Spindle Speed Variation ◽

Free Region ◽

Continuation Algorithm

This paper investigates the regenerative chatter in a plunge grinding process. The effect of the contact force on the onset of chatter vibration is clarified by a proposed continuation algorithm, and the boundary for the chatter-free region in which the grinding process is stable is obtained. By varying the rotational speed of the workpiece continuously, the chatter vibration with the values of the system parameters being near the boundary is suppressed, namely, the chatter-free region is expanded by this spindle speed variation control strategy.

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Thermal deformation rate of grinding wheel in plunge grinding process.

Journal of the Japan Society for Precision Engineering ◽

10.2493/jjspe.55.354 ◽

1989 ◽

Vol 55 (2) ◽

pp. 354-359 ◽

Cited By ~ 1

Author(s):

Toshikatsu NAKAJIMA ◽

Shinya TSUKAMOTO ◽

Kazunobu SATO

Keyword(s):

Deformation Rate ◽

Thermal Deformation ◽

Grinding Wheel ◽

Grinding Process ◽

Plunge Grinding

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The analysis of a cylindrical plunge grinding process. The contact rigidity of the grinding wheel.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C ◽

10.1299/kikaic.55.451 ◽

1989 ◽

Vol 55 (510) ◽

pp. 451-454

Author(s):

Makoto OBI ◽

Shunji KUMAGAYA ◽

Kazuhiko YASUHARA ◽

Shigeru IWASATO

Keyword(s):

Grinding Wheel ◽

Grinding Process ◽

Plunge Grinding ◽

Contact Rigidity

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The method of assessment of the grinding wheel cutting ability in the plunge grinding

Open Engineering ◽

10.2478/s13531-012-0005-5 ◽

2012 ◽

Vol 2 (3) ◽

Cited By ~ 3

Author(s):

Krzysztof Nadolny

Keyword(s):

Working Conditions ◽

Comparative Assessment ◽

Grinding Wheel ◽

Grinding Process ◽

Grinding Wheels ◽

Plunge Grinding ◽

Abrasive Grains ◽

Ceramic Bond ◽

Method Of Assessment ◽

Grinding Kinematics

AbstractThis article presents the method of comparative assessment of the grinding wheel cutting ability in the plunge grinding kinematics. A new method has been developed to facilitate multicriterial assessment of the working conditions of the abrasive grains and the bond bridges, as well as the wear mechanisms of the GWAS, which occur during the grinding process, with simultaneous limitation of the workshop tests range. The work hereby describes the methodology of assessment of the grinding wheel cutting ability in a short grinding test that lasts for 3 seconds, for example, with a specially shaped grinding wheel, in plunge grinding. The grinding wheel macrogeometry modification applied in the developed method consists in forming a cone or a few zones of various diameters on its surface in the dressing cut. It presents an exemplary application of two variants of the method in the internal cylindrical plunge grinding, in 100Cr6 steel. Grinding wheels with microcrystalline corundum grains and ceramic bond underwent assessment. Analysis of the registered machining results showed greater efficacy of the method of cutting using a grinding wheel with zones of various diameters. The method allows for comparative tests upon different grinding wheels, with various grinding parameters and different machined materials.

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The Increase of the Dynamic and Static Stiffness of a Grinding Machine

Volume 2: 30th Annual Mechanisms and Robotics Conference, Parts A and B ◽

10.1115/detc2006-99740 ◽

2006 ◽

Cited By ~ 4

Author(s):

Marc Simnofske ◽

Ju¨rgen Hesselbach

Keyword(s):

Dynamic Stiffness ◽

Grinding Wheel ◽

Grinding Process ◽

Static Stiffness ◽

Process Stability ◽

Chatter Vibrations ◽

Theoretical Investigations ◽

The Stability ◽

Grinding Machine ◽

Chatter Marks

The dynamic stiffness of a grinding machine influences the process stability enormously. Among other things the stability of the grinding process is affected by influences like the specification of the grinding wheel, the condition of the workpiece and machine parameters. Unfavorable combinations of these lead to chatter vibrations of the machine and chatter marks on the workpiece. This paper presents the results of experimental and theoretical investigations of the vibration behavior of a grinding machine and the design of active modules. These modules will be implemented in the structure of the machine to minimize the vibrations and additionally increase its static stiffness of the machine.

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Modeling and experimental analysis of wheel-work interface in the cylindrical plunge grinding process

International Journal of Engineering & Technology ◽

10.14419/ijet.v3i4.3542 ◽

2014 ◽

Vol 3 (4) ◽

pp. 484

Author(s):

Tarik Tawfeek

Keyword(s):

Contact Stiffness ◽

Grinding Wheel ◽

Grinding Process ◽

Plunge Grinding ◽

Workpiece Surface ◽

Roundness Error ◽

Cylindrical Grinding ◽

Grinding Processes ◽

Proposed Model ◽

Grinding Machine

This paper presents a study of grinding wheel-workpiece interference in external cylindrical plunge grinding processes. This is to study the effect of workpiece surface memory on the workpiece roundness error after grinding. The study has been carried out theoretically on a model simulating cylindrical grinding process. The model takes contact stiffness, grinding wheel and workpiece wear into consideration. The proposed model was sued to predict the normal grinding forces in cylindrical grinding as a function of the previous height and number of waves of the initial profile.The new model has been validated by conducting experiments on a cylindrical grinding machine. Results indicate that the proposed model shows a good agreement with the experimental data obtained.The results of experiments indicate that the proposed modeling method is both feasible and reliable. The results showed that the theoretical model was effective studying the output of cylindrical grinding process. Normal grinding force, vibration level, and roundness error in cylindrical plunge grinding processes are dependent on the workpiece surface memory. Keywords: Plunge Grinding, Modeling, Roundness Error, Surface Memory.

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Stability Analysis of a Transverse Cylindrical Grinding Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.479-481.1190 ◽

2012 ◽

Vol 479-481 ◽

pp. 1190-1193

Author(s):

Yao Yan ◽

Jian Xu

Keyword(s):

Stability Analysis ◽

Grinding Wheel ◽

Force Model ◽

Grinding Process ◽

Key Factors ◽

Mass System ◽

Cylindrical Grinding ◽

Chatter Vibrations ◽

The Stability ◽

Euler Bernoulli Beam

The stability of a transverse cylindrical grinding process is investigated in this paper. The workpiece is considered as a rotating damped hinged-hinged Euler-Bernoulli beam and the grinding wheel a rotating damped spring mass system moving along the workpiece. Called regenerative force, the contact force between the workpiece and the wheel is a functional equation related to both the current and previous relative positions between the workpiece and the wheel since the regeneration exists on the surfaces of both the workpiece and the wheel. The two distinct time delays presented in the regenerative force model are inversely proportional to the rotation speeds of the workpiece and the wheel respectively. For grinding stability analysis, the regenerative effects are considered as the key factors in inducing chatter vibrations in the grinding process. The grinding stability is numerically analyzed since two distinct delays being involved in the model makes the analytical analysis extremely difficult. Finally, the grinding stability analysis is verified by numerical simulation.

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