y an unwanted miss-aligned feeding situation where more mate-rial reports to one side on the crusher than the other. This phe-nomenon was also observed visually during the experiments.The simulated pressure is calculated by exporting the total forceacting on the mantle in the vertical direction divided by the area ofthe hydraulic piston. Since a quarter section of the crusher hasbeen simulated it is natural that the cyclic behaviour is observed.This can be regarded as an extreme misaligned feeding situation.An offset for the simulated pressure has been applied to accountfor the mass of the main shaft assembly.