A large amountoffluid carrying rock debris rapidly flows out of the well when a blowout or well kick occurs. During the process of closing the blowout preventer (BOP) ram, solid particles in the drilling fluid will erode the rubber core of the ram. To address this issue, the work aims to determine the optimal erosion model for nitrile rubber and predict the erosion amount of the rubber core quantitatively, so as to provide a basis for evaluating the sealing performance of the rubber core after shut-in.