The use of polyester in mooring lines of floating structures is a very recent issue due to the
oil exploitation in deeper and deeper water. It is nevertheless a reality. After several years of
research and field evaluation, PETROBRAS decided to use polyester lines in several
floating production systems (FPS) in Campos Basin, offshore Brazil. Two of them were
installed in 1997 and others are planned for 1998 and 1999. The basic research that
sustained the feasibility of the lines has been consolidated in Del Vecchio (1992), where a …

The work presents an expression to deal with the stiffness non-linearity of polyester mooring
cables. The basis for that is a PhD thesis of the second author and full scale testing of five
inch diameter polyester mooring cables. On one hand, weak dependence on the frequency
has been detected. On the other hand, the mild to significant dependence on the average
load and load amplitude has become clear. Suggestions on how to deal with the expression
in a mooring design are also addressed. INTRODUCTION The use of polyester in mooring …