Mechanical performance analysis of hollow cylindrical roller bearing of cone bit by FEM

Abstract

Bearings are key components of cone bit, thus its rapid failure is a major cause of leading to lower life of the bit. To improve the bearing performance and prolong working life, contact mechanics of hollow cylindrical roller bearing of cone bit was simulated. Effects of hollow size, drilling pressure, friction coefficient and fitting clearance on mechanics performance of the bearing were studied. The results show that the maximum equivalent stress of the hollow cylindrical roller bearing appears on the claw journal, and the maximum contact stress appears on the contact pair of the hollow roller. Besides, hollow sizes have a greater impact on the equivalent stress and contact stress of the cylindrical roller, while the influence on the stress of the cone and claw journal is relatively small. With the increasing of the drilling pressure and fitting clearance, equivalent stress and contact stress of bearing parts increase. The friction coefficient has little impact on mechanical performance of the bearing. As the 121/4SWPI517 type hollow cylindrical roller bearing of cone bit an example, the optimal hollow size is 55%, the drilling pressure is 140 kN and the fitting clearance is 0-0.02 mm.

Keywords

Cone bit / Hollow cylindrical roller bearing / Finite element method / Contact stress / Mechanical property

Acknowledgements

The Authors gratefully acknowledge finance of this study that was Supported by Science and Technology Innovation Talent Engineering Project of Sichuan Province (2014-025) and Natural Science foundation of China (51474180).

References

[1] J.Q. Chen, B. Wu, H.B. Mao, Failure analysis of rock-bit roller bearing and measures for life enhancement, J. Lubr. Seal. 26 (16) (2001) 38-42.

[2] C.J. Han, J. Zhang, The contact analysis of hollow cylindrical roller bearing in different load conditions, J. Mach. Des. Manuf. 49 (11) (2012) 214-216.

[3] J.Q. Chen, H.B. Mao, B.S. Zhang, The theory study of the hollow cylindrical roller bearing without the pre-load, J. Bear. 6 (2002) 1-5.

[4] H. Luo, J.J. Liu, Analysis of contact problems on hollow cylindrical roller, J. Tribol. 17 (3) (1997) 254-259.

[5] J.Q. Chen, P. Zhang, L.L. Xu, The theory of the hollow cylindrical roller bearing of cone bit, J. Pet. Mach. 29 (9) (2001) 5-8.

[6] C.J. Han, J. Zhang, G.Q. Jiang, A hollow roller composite bearing design for cone bits, J. Nat. Gas Ind. 33 (3) (2013) 53-58.

[7] W.J. Li, C.Y. Pan, R.J. Wang, An analytical method for calculating of hollow cylindrical roller contact deformation, J. Bear. 51 (8) (2009) 1-5.

[8] Y.K. Liu, T.M. Guan, Y.G. Wei, Study of the performance of pre-loaded hollow cylindrical roller bearings including temperature field, J. Lubr. Eng. 38 (3) (2013) 44-47.

[9] J. Zhang, Z. Liang, C.J. Han, Numerical study on deep cavity hollow cylindrical roller bearing for cone bit, J. Mech. Strength 36 (5) (2014) 723-727.

[10] H.C. Zhang, B. He, From the Entry to Actual Combat about Finite Element Analysis of ANSYS13.0, China Machine Press, Beijing, 2011, pp. 48-63.

[11] The Lab of Drilling Bit in Southwest Petroleum Institute, User Manual of Tri-cone Bit, Sichuan Petroleum Administration Bureau Scientific and Technical Publishers, Sichuan, 1978.