The present work aims to represent the sedimentation curve of different industrial pulps through the Weibull model PDF, which employs two parameters k and gamma, dispensing the graphical methods to design thickeners and clarifiers, using exclusively mathematical equations. This provides greater accuracy and increases significantly the speed in sizing calculations. To ratify the use of the model, sedimentation curves of various types of pulps were generated in the laboratory, several types of curves were obtained through tests given in the literature and exhaustive comparison tests between the data obtained in the tests and those predicted by the model. The proposed model presented good data adjustment in relation to those obtained in several bibliographic references, presenting maximum error of 12%.