The use of steady-state models in process simulation is a well-established method in many process industries. Designing a large crushing plant by relying on steady-state simulations alone will not generally provide the full picture of possible operational performance. The dynamics and variation between equipment and stochastic events can significantly reduce predicted plant performance. In order to dynamically simulate the crushing circuit, models for process equipment need to be further developed. The purpose of this paper is to create a wear function for an existing Particle Size Distribution model (i.e., a Swebrec-function) with data obtained from a real crusher operating at gradually increasing closed side settings. This is done to create an accurate and updated model of the crusher in which the transient consequences of wear are captured. The Swebrec-function and correlation model were implemented into simulation software with simulated events: this simulation was validated with actual process readings. Improved simulations were then attained with the developed functions. (C) 2012 Elsevier Ltd. All rights reserved.