Optimization of Stinger Geometry for Deepsea Pipelaying

Abstract

The configuration of the stinger and ramps of a laying barge can be adjusted by varying the angles between adjacent segments and the arm of each support. On the basis of suitable idealizations and discretizations, a method is developed apt to optimize, for a given laying situation, the choice of the foregoing geometric parameters, alone at given tension or in association with the tensioner thrust. In the former case the function to minimize is the maximum absolute value of the bending moment in the overbend. In the latter case the thrust at the tensioner is minimized for given upper bound on the maximum stress in the overbend. The optimization procedure proposed consists of three phases and allows for unilateral contact between pipe and supports.