Dynamic Stability of a Motorized High Speed Machine Tool Spindle Supported on Bearings

Abstract:

Dynamic behaviour of spindle system influences chatter stability of machine tool considerably. Self-excited vibrations of the tool results in unstable cutting process which leads to the chatter on the work surface and it reduces the productivity. In this paper, a system of coupled spindle bearing system is employed by considering the angular contact ball bearing forces on stability of machining. Using Timoshenko beam element formulation, the spindle unit is analyzed by including the gyroscopic and centrifugal terms. Frequency response functions at the tool-tip are obtained from the dynamic spindle model. In the second phase, solid model of the system is developed and its dynamic response is obtained from three dimensional finite element analysis. The works on analysis of the stability of milling processes focus on calculating the stability boundary of the machining parameters based on the dynamic models characterizing the milling processes. The stability lobe diagrams are generated from frequency response functions (FRF’s) lead to an stability limit prediction for the system at high speed ranges.

• Periodical: Applied Mechanics and Materials (Volume 612)
• Pages: 29-34
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.612.29
• Online since: August 2014
• Authors: Jakeer Hussain Shaik*, J. Srinivas
• Keywords: Bearing Contact Forces, Solid Modeling, Spindle Dynamics, Stability

References

[1] Y. Altintas, E. Budak, Analytical prediction of stability lobes in milling, Annals of the CIRP. (1995) 357-362.

DOI: 10.1016/s0007-8506(07)62342-7

[2] S.H. Gao, G. Meng, Unstable islands and bifurcation analysis in a spindle Milling system supported by ball bearings, J. of Multi-body Dynamics. (2011).

DOI: 10.1177/1464419311408500

[3] W.X. Tanga, Q.H. Songa, Prediction of chatter stability in high-speed finishing end Milling considering multi-mode dynamics, Int. J. Machine Tools & Manf. 209 (2009) 2585-2591.

DOI: 10.1016/j.jmatprotec.2008.06.003

[4] V. Gagnola, B.C. Bouzgarrou, P. Ray, C. Barra, Model-based chatter stability prediction for high-speed spindles, Int. J. Machine Tools & Manf. 47 ( 2007) 1176-1186.

DOI: 10.1016/j.ijmachtools.2006.09.002

[5] Mane, V. Gagnol , B.C. Bouzgarrou, P. Ray, Stability-based spindle speed control during flexible workpiece high-speed milling, Int. J. Machine Tools & Manf. 48 (2008) 184-194.

DOI: 10.1016/j.ijmachtools.2007.08.018

[6] E. Solis, C.R. Peres, J.E. Jimenez, J.R. Alique, J.C. Monje, A new analytical-experimental method for the identificationof stability lobes in high-speed milling, Int. J. Machine Tools & Manf. 44 (2004) 1591-1597.

DOI: 10.1016/j.ijmachtools.2004.06.011

[7] H. Cao, B. Li, Z. He, Chatter stability of milling with speed- varying dynamics of spindles, Int. J. Machine Tools & Manf. 52 (2012) 50-58.

DOI: 10.1016/j.ijmachtools.2011.09.004

[8] H. D Nelson, A finite rotating shaft element using Timoshenko beam theory, Trans. ASME J. Mech. Des. 102 (1980) 793-803.

DOI: 10.1115/1.3254824

[9] D. Liu, H. Zhang, Z. Tao, Y. Su, "Finite element analysis of high-speed motorized spindle based on ANSYS, The open Mechanical Engineering Journal. 5 (2011) 1-10.

DOI: 10.2174/1874155x01105010001