Numerical Model to Simulate Tensile Wire Behavior in Unbonded Flexible Pipe During Bending

The tensile wires in flexible pipe play an important role for forming the axial strength and stiffness of the pipe and for supporting the pressure armoring wires to resist the internal pressure. In the meanwhile, the fatigue life of the flexible pipe is generally often limited by the tensile wire life because the stress variations in the wires are considerably greater than those in other metal layers of the pipe. Therefore, exactly understanding and evaluating tensile wire behaviors are significantly important and necessary. In other words, as long as the behaviors of tensile wires can be evaluated the working mechanism of pipe bending can be evaluated.