Patent ID: 6022174
Filing Date: 2000-02-08
Classification: B63B

Abstract:
A method for installing an offshore tension leg platform, comprising the steps of bringing a freely floating platform structure (7) to a temporary draft which is somewhat larger than normal draft in operating condition, bringing the platform structure (7) into a predetermined position with respect to substantially vertically arranged tension legs (1), which in advance have been attached to one or more foundations (2) on the sea floor (3) and which at their upper ends have been provided with a coupling element, guiding the tension legs (1) in place with respect to the platform structure (7) so that their coupling elements (5) assume a position a distance above the corresponding connection means (9) on the platform structure (7), and causing a relative movement between the coupling elements (5) and the platform structure (7) in order to bring the coupling elements (5) to rest against a seat in the corresponding connecting means (9), whereupon further tensioning of the tension legs (1) takes place by reducing the ballast of the platform structure (7), characterized in that the coupling elements (5), except in their end position, are permitted to move substantially without vertical constraint with respect to the connecting means (9) during a final stage of said relative movement and to impact in said end position against the seat in the corresponding connecting means (9).