Ensuring accuracy of contour milling on CNC machines

Authors

  • Yuri Petrakov Igor Sikorsky Kyiv Polytechnic Institute, Kyiv, Ukraine , Ukraine https://orcid.org/0000-0002-0525-4769
  • Yan Romanov Igor Sikorsky Kyiv Polytechnic Institute, Kyiv, Ukraine , Ukraine

DOI:

https://doi.org/10.20535/2521-1943.2023.7.1.276162

Keywords:

contour milling, correction of the control program, modeling of the contour milling

Abstract

Contour milling is characterized by quasi-stationary, which leads to the occurrence of a machining error caused by elastic deflections of the machining system. Moreover, such an error cannot be eliminated by sub-adjusting the control program "for size", since it not is constant and changes along the contour in a wide range. To ensure the accuracy of contour milling, a new method of combined control is proposed, which uses a posteriori information of machine verification measurements of the machined surface and a priori information of modeling the material removal process. In case of single manufacturing, the allowance on the last pass is divided into two parts, and after machining the first part, verifications are performed, then modeling and machining of the second half according to the corrected control program. In mass manufacturing, verifications are performed on the first part, and all subsequent ones are machined according to the adjusted control program. To obtain the necessary a posteriori information, the technology of machine verifications on CNC-machine with a three-coordinate probe according to standard control programs is proposed, and it is enough to perform two measurements or one, in the presence of surfaces inclined to the coordinate axes of the contour. A computer program was created, the core of which is a mathematical model of the process, which reproduces the structural diagram of the machining system closed behind two elastic deflections. The primary control file is loaded in G-codes with measurement data, and as a result of the process simulation, a new control file for the CNC-machine tool is formed, which eliminates the error from elastic deflections of machining system. Preliminary tests showed the possibility of increasing the accuracy of contour machining by more than 3 times.

References

  1. J. Niu, J. Xu, F. Ren, Y. Sun and D. Guo, “A short review on milling dynamics in low-stiffness cutting conditions: Modeling and analysis”, Journal of Advanced Manufacturing Science and Technology, vol. 1, no. 1, p. 2020004, 2021. DOI: https://doi.org/10.51393/j.jamst.2020004.
  2. Solid CAM. The Leaders in integrated CAM. Available: https://www.solidcam.com/ru/imachining/.
  3. Y. V. Petrakov and А. V. Myhovych, “IMachining technology analysis for contour milling”, Mechanics and Advanced Technologies, no. 2 (89), pp. 114-120, 2020. DOI: https://doi.org/10.20535/2521-1943.2020.89.202065.
  4. Kris M. Y. Law and A. Geddam, “Prediction of contour accuracy in the end milling of pockets”, Journal of Materials Processing Technology, vol. 113, no. 1–3, pp. 399–405, Jun. 2001. DOI: https://doi.org/10.1016/S0924-0136(01)00594-5.
  5. Xiong Han and Limin Tang, “Precise prediction of forces in milling circular corners”, International Journal of Machine Tools and Manufacture, vol. 88, pp 184–193, Jan. 2015. DOI: https://doi.org/10.1016/j.ijmachtools.2014.09.004.
  6. Y. Yang, W.-H. Zhang, Y.-C. Ma and M. Wan, “Chatter prediction for the peripheral milling of thin-walled workpieces with curved surfaces”, International Journal of Machine Tools and Manufacture, vol. 109, pp. 36–48, 2016. DOI: https://doi.org/10.1016/j.ijmachtools.2016.07.002.
  7. T. L. Schmitz and B. P. Mann, “Closed-form solutions for surface location error in milling”, International Journal of Machine Tools and Manufacture, vol. 46, no. 12-13, pp. 1369–1377, 2006. DOI: https://doi.org/10.1016/j.ijmachtools.2005.10.007.
  8. Y. Altintas, Manufacturing Automation: Metal Cutting Mechanics, Machine Tool Vibrations, and CNC Design, 2nd ed. Cambridge University Press, 2012, 366 p. DOI: https://doi.org/10.1017/CBO9780511843723.
  9. A. Jacso and T. Szalay, “Optimizing the numerical algorithm in Fast Constant Engagement Offsetting Method for generating 2.5D milling tool paths”, The International Journal of Advanced Manufacturing Technology, vol. 108, no. 7-8, pp. 2285–2300, 2020. DOI: https://doi.org/10.1007/s00170-020-05452-1.
  10. C. Liu, Y. Li and W. Shen, “A real time machining error compensation method based on dynamic features for cutting force induced elastic deformation in flank milling”, Machining Science and Technology, vol. 22, no. 5, pp. 766-786, 2018. DOI: https://doi.org/10.1080/10910344.2017.1402933.
  11. T. C. Bera, K. A. Desai and P. V. M. Rao, “Error compensation in flexible end milling of tubular geometries”, Journal of Materials Processing Technology, vol. 211, no. 1, pp. 24–34, 2011. DOI: https://doi.org/10.1016/j.jmatprotec.2010.08.013.
  12. Y. Petrakov, V. Korenkov and A. Myhovych, “Technology for programming contour milling on a CNC machine”, Eastern-European Journal of Enterprise Technologies, vol. 2, no. 1 (116), pp. 55–61, 2022. DOI: https://doi.org/10.15587/1729-4061.2022.255389.
  13. M. Schwenzer, S. Stemmler, M. Ay, T. Bergs and D. Abel, “Continuous identification for mechanistic force models in milling”, IFAC-PapersOnLine, vol. 52, no. 13, pp. 1791–1796, 2019. DOI: https://doi.org/10.1016/j.ifacol.2019.11.461.
  14. Renishaw. Inspection plus software for HAAS machining centres. Programming manual H-2000-6222-0A-B, 2008. Available: https://www.haascnc.com/content/dam/haascnc/en/service/manual/probe/english---renishaw-inspection-plus---programming-manual---2008.pdf.

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Published

2023-04-13

How to Cite

[1]
. Y. Petrakov and Y. Romanov, “Ensuring accuracy of contour milling on CNC machines”, Mech. Adv. Technol., vol. 7, no. 1 (97), pp. 51–60, Apr. 2023.

Issue

Vol. 7 No. 1 (97) (2023)

Section

Up-to-date machines and the technologies of mechanical engineering

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Copyright (c) 2023 Юрій Володимирович Петраков, Юрій Романов

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