Statistical Modeling of Pin Gauge Dimensions of Root of Gas Turbine Blade in Creep Feed Grinding Process
Creep feed grinding is a recently invented process of material handling. It combines high quality of the piece surface, productivity, and the possibility of automatic control. The main objectives of this research is to study the influences of major process parameters and their interactions of creep feed grinding process such as wheel speed, workpiece speed, grinding depth, and dresser speed on the pin gauge dimensions of root of gas turbine blade by design of experiments (DOE). Experimental results are analyzed by analysis of variance (ANOVA) and empirical models of pin gauge dimensions of root are developed. The study found that higher wheel speed along with slower workpiece speed, lower grinding depth and higher dresser speed, cause to obtain best conditions for pin gauge dimensions of root.
Selections of working conditions for creep feed grinding. Part(III): avoidance of the workpiece burning by using improved BP neural network
In this study, the grinding force of the creep feed grinding are modeled and forecasted by using the improved back propagation neural (BPN) network. The results show that the grinding energy can be accurately predicted by the application of the grinding force model. Due to the previous paper, the workpiece burning occurs as the grinding energy is greater than the critical grinding. Thus, a judgment for the occurrence of the workpiece burning can be achieved. Comparing with the experimental results, the applied algorithm of the improved BPN network is proved to be effective in forecasting the working conditions of the workpiece burning. Thus, a selection scheme of working conditions in view of the avoidance of the workpiece burning is further developed. Considering the working efficiency, the working conditions are selected to maximum metal removed rate, MRRmax. The results show that a larger size of wheel is available to have a better working efficiency.
Workpiece Burn and Its Prediction in Creep Feed Grinding — Experimental Research of the Temperature Variance Process in Contact Zone
Summary On the basis of improving the experimental technique, the authors have obtained a set of experimental curves by developing uniquely designed experiments. The temperature distribution and its variance characteristics in contact zone during entire creep feed grinding process can be fully explored. According to the newly discovered experimental results, it was confirmed that the heating state of continuously renewed grinding surface during film boiling of coolant in creep feed grinding is quite different from that of boiler tubes. There exists a gradually developing process from low surface temperature in normal condition to burning temperature in contact zone during creep feed grinding. Therefore the prediction of workpiece burn can be realized. At the end of this paper, a scheme is proposed for in process prediction of workpiece burn during creep feed grinding used in production.