摘要：Deepwater pipelines are designed to withstand, without collapsing, the external
pressure and bending imposed on them, either by the laying process or by the
topology of the sea bottom. In previous publications CINI researchers have
developed finite element models to predict collapse loads and collapse
propagation loads. Large diameter pipes for onshore and offshore applications
are manufactured using the UOE process. The manufacturing process consists in
the cold forming of heavy plates followed by welding and then by an
expansion. First the plate is pressed along its edges, formed into a U-shape and
then pressed into an O-shape between two semicircular dies. Afterwards the
pipe is welded by SAW process and finally is expanded. In this paper we
develop a 2D finite element model to simulate the UOE process and the
structural behavior of the formed pipes in external pressure collapse tests.
Using the developed model we can analyze the effects of the process
parameters in each forming step on the final geometry and
structural properties of the pipe.
