Monitoring and evaluation of process parameters in a plunge grinding operation

SUMMARY

Plunge grinding, like other grinding operations, is a complex process because of a large number of factors that are involved. This often makes it difficult to determine the optimal grinding parameters in pursuit of a certain product quality and cost, based upon the existing generic knowledge and experience about the process. However, the combined effect of the large number of factors and therefore, the performance characteristics of a given grinding system (including grinding wheel, component, grinding machine as well as workpiece holding system) can be learned by monitoring the grinding process. This can then help in the determination of optimal or near optimal grinding parameters. The paper describes a computerised system for the analysis of a plunge grinding operation based on the monitored power traces. This analysis yields data on important parameters such as grinding power (P), specific energy (E⊂s⊂), grinding force (F⊂t⊂), system deflection (Δy) and stiffness (K⊂s⊂). The paper also discusses the evaluation models used in the system, in particular, the model proposed for evaluation of system deflection and stiffness. The effect of the system stiffness on grinding process is analysed and a method to determine spark-out period, required to eliminate the system deflection, is proposed in the paper.