Shunmugam M S

Surface topography of cylinder liners plays an important role in terms of functionality of the engine. The surface is finished by honing process in various stages namely rough, finish and finally plateau honing to have proper plateau portion (bearing area) at the top to resist wear and grooves at desired honing angle to retain lubrication during engine operation. Selection of parameters and their levels in plateau honing operations to achieve required surface topography is found to be very difficult. For the first time, data mining approach is used in this investigation to select significant honing parameters and their levels considering two important bearing area parameters namely core roughness depth (R k) and material portion in the valley zone (M r2) together. Data mining model was trained and tested using experimental data. The significant input plateau honing parameters have been identified and graphical representation of the decision tree has been also presented for easier understanding. Copyright © 2010 Inderscience Enterprises Ltd.

Sensing Acoustic Emission (AE) signals from a machining process is one of the most promising methods suitable for tool condition monitoring because of its sensitivity combined with quick and high frequency response. In this work, AE signals are monitored during rough, finish and plateau honing of cylinder liner using fresh and completely worn out honing tools. AE parameters such as Root Mean Square (RMS), peak to peak, skewness and kurtosis and dominant frequency in the power spectrum are analysed. The results show that the dominant frequency in the power spectrum is very sensitive to honing tool conditions and a good correlation exists with honed surface quality. Therefore, AE signals can be used for ascertaining the honing tool performance and establishing the end of tool life. Copyright © 2008, Inderscience Publishers.

Development of cylinder liner for internal combustion engines is a challenging task and it involves a thorough understanding of interaction between functional requirements of liners, performance of honing process and desired surface characteristics. In the present work, an attempt is made to bring out the relation between performance of honing process and surface characteristics with the condition of the honing tools. Signals from multiple sensors during rough, finish and plateau operations with fresh or worn out tools show a good correlation between honing tool condition and performance measures such as material removal and surface topography. A strange phenomenon of reduced amplitude in power spectrum of vibration signals occurring with worn out tools is explained. On comparing the acoustic emission (AE) signals and the signals obtained from piezoelectric cutting force dynamometer and accelerometer, it is found that the signals obtained from AE sensor show higher sensitivity in terms of performance measures. A tool condition monitoring strategy which considers all three sensors including AE sensor is proposed in this paper. Such a strategy would help in the timely replacement of the honing tools, thereby enhancing the productivity. Copyright © 2012 Inderscience Enterprises Ltd.

Surface topography of cylinder liners influences the functional behaviour of internal combustion engines. The cylinder liners after boring operation are subjected to rough, finish and plateau honing operations in which parameters such as rotary speed, reciprocating speed, pressure and honing time are selected on the basis of operator's experience. The present work is a comprehensive investigation carried out to identify the significant honing parameters and their values for different honing operations. The honing trials are carried out according to design of experiments. Before each operation, all cylinder liners are processed identically under conditions identified from the previous operation. Parameters considered for characterising the surface topography are roughness average (Ra) and all five bearing area parameters (Rpk, Rk, Rvk, Mr1 and Mr2). It is established in the present work that Ra can be replaced effectively by Rk in finish and plateau honing operations to control the final surface topography and these parameters (Ra, Rk) are influenced by honing pressure. For the most important bearing area parameter Mr2, the significant process parameters are medium honing time in finish honing and high reciprocating speed in plateau honing. These results are useful for controlling the honing operations during the manufacture of the cylinder liners. Copyright © 2009, Inderscience Publishers.