ABSTRACT
Rubber covered nip rolls have a number of applications in the paper industry. One of them is the coating process, where color or size is applied on one or both sides of the paper web. Paper's tendency of form "uncoated wrinkles" can be diminished by choosing the optimum crowning shape for the rolls as a function of nip load and cover material parameters. The Split Hopkinson Pressure Bar method is based on the propagation of one-dimensional elastic pressure waves in two slender bars, between which the specimen is placed. To obtain the nip pressure profile in machine and cross machine directions, the contact between the rolls was modeled in Abaqus using a 3D nonlinear static analysis. In order to decrease the nip pressure gradient in production conditions, the shape of the rolls can be modified by changing the crowning profile.
