0
TECHNICAL PAPERS

Test Results for PTFE-Faced Thrust Pads, With Direct Comparison Against Babbitt-Faced Pads and Correlation With Analysis

[+] Author and Article Information
C. M. Ettles

Tribology Group, Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180-3590e-mail: ettlec@rpi.edu

R. T. Knox

Michell Bearings Ltd, Scotswood Road, Newcastle-upon-Tyne, NE15 6LL, UKe-mail: KNOX-R@michellbearings.co.uk

J. H. Ferguson

GE Hydro, General Electric Canada Inc, 107 Park Street North, Peterborough, Ontario K9J 7B5, Canadae-mail: james.ferguson@ps.ge.com

D. Horner

Michell Bearings Ltd, Scotswood Road, Newcastle-upon-Tyne, NE15 6LL, UKe-mail: HORNER-D@michell.bearings.co.uk

J. Tribol 125(4), 814-823 (Sep 25, 2003) (10 pages) doi:10.1115/1.1576427 History: Received March 12, 2002; Revised August 09, 2002; Online September 25, 2003
Copyright © 2003 by ASME
Your Session has timed out. Please sign back in to continue.

References

Aleksandrov, A. E., 1981, “Use of Elastic Metal-Plastic Segments with a Fluoric Plastic Covering on Friction Surfaces in Hydro-Turbine Thrust Bearings,” Gidtrotekhnicheskoe Stroitelstvo, (9), pp. 12–14.
Shen, W-Y., 1994, “Development of Teflon-Lined Thrust Bearing Pads on Medium and Large Hydro-Electric Units in China,” Unpublished, photocopies can be provided on request for individual, personal use.
Simmons,  J. E. L., Knox,  R. T., and Moss,  W. O., 1998, “The Development of PTFE (polytetraflorethylene)—Faced Hydrodynamic Thrust Bearings for Hydrogenerator Application in the United Kingdom,” Proc. Inst. Mech. Eng., Part J: J. Eng. Tribol., 212, pp. 345–352.
Knox, R. T., July 1998, “The Development of PTFE-Faced Thrust Bearings for Hydro Generator Power Plant,” Hydrovision 98, Reno, Nevada.
Mohino, A., Loshkarev, V., and Goldenberg, S., 2001, “PTFE Thrust Bearings for Hydro Generating Units: Present, Past and Future,” Waterpower XII.
Horner,  D., Simmons,  J. E. L., and Advani,  S. D., 1998, “Measurements of Maximum Temperature in Tilting-Pad Thrust Bearings,” STLE Tribol. Trans., 31, pp. 44–53.
Yuan,  J. H., Medley,  J. B., and Ferguson,  J. H., 1999, “Spring-Supported Thrust Bearings Used in Hydroelectric Generators: Laboratory Test Facility,” STLE Tribol. Trans., 42, pp. 126–135.
Ettles,  C. M., 1991, “Some Factors Affecting the Design of Spring Supported Thrust Bearings in Hydroelectric Generators,” ASME J. Tribol., 113, pp. 626–632.
Ettles,  C. M., 1998, “Three-Dimensional Thermoelastic Solutions of Thrust Bearings Using Code Marmac 1,” ASME J. Tribol., 113, pp. 405–412.
Rightmire, G. K., Castelli, V., and Fuller, D. D., 1976, “An Experimental Investigation of a Tilting-Pad, Compliant-Surface, Thrust Bearing,” ASME J. Lubr. Technol., pp. 95–108.
Robinson,  C. L., and Cameron,  A., 1975, “Studies in Hydrodynamic Thrust Bearings,” Philos. R. Soc. London, Ser. A, 278, pp. 351–366.
Gardner,  W. W., 1988, “Tilting Pad Thrust Bearing Tests—Influence of Pivot Location,” ASME J. Tribol., 110, pp. 609–613.
Raimondi,  A. A., 1960, “The influence of Longitudinal and Transverse Profile on the Load Capacity of Pivoted Pad Bearings,” ASLE Trans., 3, pp. 265–276.
Yuan,  J. H., Medley,  J. B., and Ferguson,  J. H., 2001, “Spring-Supported Thrust Bearings Used in Hydroelectric Generators: Comparison of Experimental Data With Numerical Predictions,” STLE Tribol. Trans., 44, pp. 27–34.
Yuan, J. H., 2000, “Experimental Investigation of Large Spring-Supported Thrust Bearings Used in Hydroelectric Generators,” Ph.D. thesis, Mechanical Engineering Department, University of Waterloo.
Zhang,  Z. Z., Xue,  Q. L., Liu,  W. M., and Shen,  W. C., 1988, “Friction and Wear Characteristics of Lead and its Compounds Filled Polytetraflorethylene Composites Under Oil Lubricated Conditions,” Tribol. Int., 31(7), pp. 361–368.

Figures

Grahic Jump Location
Creep properties of pure PTFE in compression at 100°C
Grahic Jump Location
(a) Dimensions of pads in bearing #1; (b) tapers on lead and trail edges; and (c) edge support in bearing #2
Grahic Jump Location
(a) Measured and computed temperatures in bearing #1 at location “a” (Fig. 2(a)) at the 57%, 84% radial/circumferential position. Speed 800 rpm, bath temperature 49–51°C. Results for location “a” with the thermocouple encapsulated in PTFE are shown as half-filled symbols, in the range 51–58°C; and (b) measured and computed power loss at 800 rpm.
Grahic Jump Location
Comparison of measured power loss for two designs of PTFE-faced pads and for babbitt-faced pads in bearing #1 configuration at 6–7 MPa, bath temperature 49–51°C
Grahic Jump Location
(a) Computed film profiles on the mean radius for bearing #1 with PTFE face; and (b) corresponding pressure profiles
Grahic Jump Location
Illustration of end constriction found by Rightmire et al. 10, reproduced from the ASME Journal of Lubrication Technology, with acknowledgements
Grahic Jump Location
Computed isobars of pad face temperature, pressure and film thickness for bearing #1: (a, b, c) PTFE-faced, 2.9 MPa, 800 rpm; and (d, e, f) Babbitt-faced, 9.0 MPa, 800 rpm.
Grahic Jump Location
Bearing #2: (a) Babbitt-faced: Measured and computed temperatures at 5 MPa for locations a,b,c. The measured values are shown as filled symbols and computed values as open symbols. (The locations a,b,c,d are 21 mm from the back face, at the nondimensional radial/circumferential positions (%,%) 61–85, 89–67, 13–22, 61–63); and (b) PTFE-faced: Measured and computed temperatures at locations a,d at 5 MPa (Measured values—filled symbols; computed values—open symbols. The “maximum local” face temperature occurred at the 100–100 location).
Grahic Jump Location
Temperature distribution through the thickness of the pads for the PTFE and babbitt-faced pads at the 50–88 position for 5 MPa and 300 rpm
Grahic Jump Location
Measured and computed power loss for bearing #2 at 5 MPa, with PTFE and babbitt-faced pads
Grahic Jump Location
Computed isobars of pad face temperature, pressure and film thickness for bearing #2: (a, b, c) PTFE-faced, 4.6 MPa, 300 rpm; and (d, e, f) Babbitt-faced, 5.0 MPa, 300 rpm
Grahic Jump Location
Computed isobars of pad face temperature, pressure and film thickness with allowance for the erosion channel extending from the oil lift hole; at 2.8 MPa and 300 rpm
Grahic Jump Location
Profilometer traces 1,2 across a pad of bearing #1
Grahic Jump Location
Schematic of possible flow of PTFE and the development of locally crowned areas
Grahic Jump Location
Schematic of pad face of bearing #1, showing position of traces 1,2 and eroded areas

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In