Experimental studies on the effects of reduction in gear tooth stiffness and lubricant film thickness in a spur geared system

Abstract Gears are one of the most common mechanisms for transmitting power and motion and their usage can be found in numerous applications. Studies on gear teeth contacts have been considered as one of the most complicated applications in tribology. Depending on the application, the speed and load conditions of teeth may change triggering several types of failures on teeth surface such as wear, scuffing, micro-pitting and pitting. The above-mentioned faults influence changes in vibration and acoustic signals, due to changes in operating conditions such as increase in temperature and decrease in lubricant film thickness and specific film thickness. These abnormal changes result in cumulative effects on localised or distributed faults on load bearing surfaces of gears. Such damages cause reduction in tooth stiffness and severity of damage can be assessed by evaluating the same using vibration-based signals. This paper presents the results of experimental investigations carried out to assess wear in spur gears of back-to-back gearbox under accelerated test conditions. The studies considered the estimation of operating conditions such as film thickness and their effects on the fault growth on teeth surface. Modal testing experiments have been carried out on the same gear starting from healthy to worn out conditions to quantify wear damage. The results provide a good understanding of dependent roles of gearbox operating conditions and vibration parameters as measures for effective assessment of wear in spur gears.

[1]  Donald R. Houser,et al.  Optimum Profile Modifications for the Minimization of Static Transmission Errors of Spur Gears , 1986 .

[2]  Jorge H.O. Seabra,et al.  Wear and scuffing of austempered ductile iron gears , 1998 .

[3]  Andrew Ball,et al.  Gear tooth stiffness reduction measurement using modal analysis and its use in wear fault severity assessment of spur gears , 2003 .

[4]  Akira Ishibashi,et al.  Effects of Overloading at the Commencement of Running upon Accuracy and Surface Durability of Gears , 1971 .

[5]  David,et al.  A comparative experimental study on the diagnostic and prognostic capabilities of acoustics emission, vibration and spectrometric oil analysis for spur gears , 2007 .

[6]  A. Davies,et al.  Handbook of Condition Monitoring , 1998 .

[7]  A. Cameron Basic lubrication theory , 1976 .

[8]  Anders Flodin,et al.  Wear of spur and helical gears , 2000 .

[9]  Jorge H.O. Seabra,et al.  Scuffing and lubricant film breakdown in FZG gears. Part I. Analytical and experimental approach , 1998 .

[10]  Paula J. Dempsey Gear Damage Detection Using Oil Debris Analysis , 2001 .

[11]  David,et al.  Identification of the acoustic emission source during a comparative study on diagnosis of a spur gearbox , 2005 .

[13]  Bernd-Robert Höhn,et al.  Influence of oil temperature on gear failures , 2004 .

[14]  Jorge H.O. Seabra,et al.  Scuffing and lubricant film breakdown in FZG gears Part II. New PV scuffing criteria, lubricant and temperature dependent , 1998 .

[15]  Zhongxiao Peng,et al.  An integrated approach to fault diagnosis of machinery using wear debris and vibration analysis , 2003 .

[16]  Cheng-Kuo Sung,et al.  Locating defects of a gear system by the technique of wavelet transform , 2000 .