A numerical study on differential pressure needed for ball pig motion in pipelines based on nonlinear hyperelastic material model

In this paper, numerical investigations are carried out in order to evaluate the essential differential pressure for running a ball pig in a pipeline. 2nd order polynomial hyperelastic material model, fitted to uniaxial tension test data of sample polyurethane, is utilized as the material model. Four main parameters include pipe internal diameter, ball pig oversize ratio to pipe internal diameter, ball pig thickness ratio, and ball pig material hardness are investigated via finite element simulations. It is shown that the differential pressure is a linear function of the ball pig thickness ratio as well as the material hardness while is a polynomial function of the oversize ratio factor. Moreover, the differential pressure does not considerably depend on the absolute value of pipe internal diameter. Results can help pigging operators and manufacturers having more accurate prediction of differential pressure needed for pipeline cleaning and de-watering via ball pigs.