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Slowly all parts are arriving to assemble the large load rolling test bench. In the meantime sampled/continuous model of milling is close to be finished.

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News

01/09/2020

The body of the high load force sensor has been manufactured.

10/06/2020

Watts-Ford measurement was carried out in the Department of Materials Science and Engineering .

14/05/2020

The CIRP Annals paper about the tunable table was published online.

03/05/2020

The transformation between two different variable helix definitions are presented in ASME Journal of Manufacturing Science and Engineering

09/03/2020

Latin cube fitting was performed on finite element results.

15/01/2020

The special tunable table for thin-walled workpieces are submitted to CIRP Annals

05/09/2019

By the help of Adam Kiss and the equipment of previous NKFI (OTKA) PD 108779 the surface of the small scale rolling measurement was scanned by using laser displacement sensor.

27/08/2019

The PI gave a plenary talk in the Hungarian Mechanical Conference (MAMEK XIII) with the title “Marási eljárások lineáris stabilitásának vonzási tartománya”.

24/08/2019

The PI participated in the CIRP General Assembly in Birmingham, where he met with prominent researchers in the field. The group participated on a paper and presentation in the conference with the title: “Analysis of the beating frequencies in dressing and its effect in surface waviness”.

20/08/2019

The PI organized a session with three minisymposia in the ASME IDETC-CIE MSNDC conference (MSNDC-7: Time-varying and time-delay systems, energy harvesting) with 14 participants. The group members of NKFI FK 124361 also gave presentations in the session. The PI was an author in two presentations: “Optimization of Edge Geometry of Cylindrical Milling Tools to Enhance Dynamic Stability” and “Stability of Variable Pitch Milling Tools in Interrupted Cutting Processes”, while David Lehotzky presented his work with the title “Modeling and stability of milling processes with active damping”.

28/06/2019

Aluminum tests were performed using AL99.5 and AlCu2024 materials. Force evaluations were measured with a Kistler force plate.

26/06/2019

The first preliminary test were performed using the small home made roller. This test is only a trial before a measurement where piezoelectric forceplate will be used.

20/06/2019

The rolling force team has visited the IK4-Ideko and CAF.

24/05/2019

The shaft for the small-scale AL measurement is certified and the maximum load has been determined.

05/05/2019

The PI was one of the lecturer in the initial CISM (International Centre for Mechanical Sciences) course in Udine in Italy. The event was supported by CISM and ERC SIREN Adv grant of Prof. Gabor Stepan.

30/04/2019

Stiffness calculation was performed by considering spring elements for the rolling parts of bearings and linear guides. This calculation showed 3.62e8 N/m stiffness by not considering the foundation of the force sensor superstructure. By using replaceable elements the stiffness can be lowered with the special design of the force sensor.

20/04/2019

The heat threatement of the roller for aluminium was performed to reach the required surface hardness.

11/04/2019

Revision was submitted by the title: "Delayed Feedback Control for Chatter Suppression in Turning Machines".

04/04/2019

Parts are ready for the "small-scale" testing with aluminium. The roller would go through heat treatement, while the shaft needs limit force certification before the tests.

08/03/2019

The rolling process is simulated using kinematical constraints only. This approach allows to omit the application of computationally expensive frictional contact conditions.

28/02/2019

Proceeding paper was submitted to the ASME IDETC/CIE 2019 MSNDC conference with the title: "Modeling and Stability of Milling Processes with Active Damping" by David Lehotzky and Zoltan Dombovari. The paper is about the effect of digital control on regenerative time-periodic dynamical system.

25/02/2019

Proceeding paper was submitted to the ASME IDETC/CIE 2019 MSNDC conference with the title: "Optimization of Edge Geometry of Cylindrical Milling Tools to Enhance Dynamic Stability" by Zoltan Dombovari, Daniel Bachrathy, Gabor Stepan. The paper is about the theoretical base of the general edge optimization scheme of a cylindrical milling cutter. The research was partially supported by ERC SIREN.

11/02/2019

Abstract has been submitted to the XIII Hungarian Mechanical Conference (MAMEK 2019) about the developed FEM model.

10/02/2019

Abstract has been submitted to the XIII Hungarian Mechanical Conference (MAMEK 2019) about attraction zones in milling. This work was partially supported by ERC SIREN

01/02/2019

The Machine Tool Vibration Course has started in the Budapest University of Technology and Economics. The course is dealing with vibration problems in machining given by Zoltan Dombovari.

31/12/2018

The NKFI FK 124361 team wishes many solvable research and engineering problems for 2019! The presented calculation is a displecement controlled version of 3D axles rolling.

31/12/2018

A journal paper was accepted for publication in Materials with the title: “Optimum Selection of Variable Pitch for Face Milling Cutters” by Alex Iglesias, Zoltan Dombovari, German Gonzales, Jokin Munoa and Gabor Stepan. The research was partially supported by ERC SIREN.

19/12/2018

The complete FEM model of axles rolling process is operating in Marc system.

17/11/2018

Two works were participating in the student competition. One is about the effect of Kalman filters and the other one is a preliminary work on digitally controlled magnetic boring bars.

10/11/2018

A journal paper was submitted about variable pitch angle optimization in Materials with the title: “Optimum Selection of Variable Pitch for Face Milling Cutters” by Alex Iglesias, Zoltan Dombovari, German Gonzales, Jokin Munoa and Gabor Stepan. The research was partially supported by ERC SIREN.

08/11/2018

A talk was given in UTIS conference in Turkey about axles rolling process with the title Basic Regenerative Modelling of Axles Rolling Process by Zoltan Dombovari , Attila Szlancsik , Kristof Bobor and Ruben Merino.

04/11/2018

The first version of the digitally controlled manuscript has been compiled. It is under in-house review.

21/10/2018

In order to have an efficient methodology to determine the rolling force and to build-up sufficient semi-analytical mechanical model w.r.t. the technological parameters, a simple parametric FEM model is compiled. This model can run with different indentation, roller-diameter and feed. The animation is about the first successful and valid run.

15/10/2018

The connection features for mounting the industrial roller shaft are designed on the force sensor. The connection surfaces with the bores and the perpendicular stiffening parts are ensuring the mechanical integrity of the device.

08/10/2018

The concept drawing of the retrofitting is finished. The concept is ready for the next iteration step which will contain the force sensor in it. The workpiece is going to be the top shaft, while the roller is going to be placed underneath. This roller is capable to perform feed motion with the linear guides.

13/09/2018

The first concept drawing of the force sensor. The forces measured on the four legs placed to the roller mounting part is enough to determine the complete 3D contact force between the roller and the workpiece shaft. The bore between the legs are the place for the threaded shaft that produces the feed motion.

04/09/2018

The proceeding paper handled in the 14th IFAC workshop on Time Delay Systems was published online in IFAC Papers online with the title: “On Basic Modeling of the Dynamics of Axles Rolling Process” by Denes Farago, Ruben Marino and Zoltan Dombovari.

08/08/2018

The 3D model of the old rolling mill is completed. We have measured the main geometric properties of the duo rolling mill that takes place in Department of Materials Science and Engineering. This old rolling mill is going to be the base of the high performance axles rolling measurements.

28/06/2018

The proceeding paper was submitted and presented in the 14th IFAC workshop on Time Delay Systems.

15/06/2018

A seminar was given by Tamás Molnar in IUTAM symposium in Novi Sad (Serbia). A two pages extended abstract was submitted with title: “Semidiscretization Method for Nonlinear Time-Periodic Time-Delay Systems”, by the authors: Tamas G. Molnar, Zoltan Dombovari, Tamas Insperger and Gabor Stepan. The talk was about the nonlinear numerical method, that is capable to predict the behavior of nonlinear periodic delayed dynamical systems.

21/03/2018

The mesh convergence test was finished. The resulting indentation-force diagrams showed that under a certain size (4mm) of the mesh does not provide better force evolution in the case of indentation-driven calculation. This is not the case in force-driven case when the results depend greatly from the mesh size.

14/11/2017

We have made the preliminary FEM modelling of the axles rolling process.

10/10/2017

The problem is specified for the digitally controlled milling process.

People

List of Meetings

30/07/2020

23/06/2020

09/06/2020

19/02/2020

07/02/2020

21/11/2019

02/10/2019

26/09/2019

19/09/2019

05/09/2019

20/06/2019

17/06/2019

05/02/2019

11/04/2019

04/04/2019

28/03/2019

14/03/2019

07/03/2019

28/02/2019

21/02/2019

14/02/2019

17/01/2019

03/01/2019

13/12/2018

06/12/2018

29/11/2018

22/11/2018

15/11/2018

18/10/2018

04/10/2018

27/09/2018

20/09/2018

13/09/2018

06/09/2018

17/08/2018

10/08/2018

31/05/2018

24/05/2018

18/05/2018

17/05/2018

10/05/2018

03/05/2018

26/04/2018

19/04/2018

27/03/2018

15/02/2018

23/01/2018

10/10/2017

03/10/2017