Simulation-based analysis of geometry-dependent wall thickness distribution in corrugated pipes

Corrugated pipes are a widely used for drainage pipes, automotive applications, and in medical engineering. In contrast to normal pipes, corrugated pipes exhibit higher stiffness and simultaneously higher flexibility by less material demand. Due to rising commodity prices and the plastic usage debate, it is of great interest to produce corrugated pipes with high quality and low material input. One major factor to manipulate the wall thickness distribution is to adapt the mold geometry. This research investigates the wall thickness distribution depending on the mold geometry. Therefor, we carried out a comprehensive parametric design study with a vast number of 2D-axisymmetric Finite Element Method (FEM) blow-molding simulations. All independent geometry parameters and the initial fluid parison thickness were varied within a wide range. Based on the data set derived by the parametric design study, we analyzed the relationships between the mold geometry and the wall thickness distribution. These key findings are crucial for the mold and pipe design with respect to optimized wall thickness distribution. In the next step, these data will be validated by experiments on a corrugated pipe plant with different molds. Moreover, an extensive multi-dimensional regression model describing the wall thickness distribution as a function of the mold geometry is planned.