The accumulation phenomenon in plunge grinding dominates the process and then leads to the existence of three distinct grinding states in one cycle, a spark-in, a steady and a spark-out state. In this paper the accumulation phenomenon is analytically described in terms of the wheel wear rate, the size generation acceleration, the grinding system stiffness, the contact stiffness and the cutting stiffness, which are characteristic parameters of the process. It is then pointed out that variations of the grinding force, the amount of size generation, the stock unremoved through a grinding cycle and the grinding cycle time can be predicted by the characteristic parameters.