Exxon Production Research Company

Technip France

Timothy Otis Weaver

Lyle D Finn

Michael Y H Luo

M Sidney Glasscock

Mark A Danaczko

Michael P Piazza

Kenneth M Steele

Thomas Wozniak

The present disclosure provides a system and method for supporting a catenary riser coupled to an offshore platform system including a pull tube and a pull tube stress joint for girth weld stress reduction and improved fatigue performance. A pull tube sleeve is coupled around a welded connection of the pull tube. The sleeve has a larger inner diameter than an outer diameter of the pull tube to form an annular space therebetween, and a fill material is filled into the space between the sleeve and the pull tube. The fill material provides a supportive coupling between the sleeve and the pull tube. The sleeve, the pull tube, or both can have gripping surfaces formed in or on their surfaces to retain the fill material in the space. The sleeve can be formed from a plurality of portions and be welded, fastened, or otherwise coupled around the pull tube.

Pull tube stress joint for offshore platform

A complaint offshore platform in which the primary restoring force to lateral displacement is established by flex piles driven into the seafloor and fixedly secured to the platform legs a preselected distance above the seafloor. The platform includes a substantially rigid space-frame structure extending from the ocean bottom to a position above the ocean surface. A drilling and production deck is secured atop the space-frame structure. Shear piles extend through the base of the space-frame structure to prevent lateral displacement of the base while permitting the space-frame structure to pivot about its base. As the platform sways about its base in response to environmental forces, the flex piles establish a vertical couple at the location at which they are attached to the space frame structure. This couple resists movement of the platform away from a vertical orientation. In the preferred embodiment, the flex piles are secured to the platform at or near one-half the total height of the space-frame structure.

Compliant offshore platform

Growing community of inventors

Houston, TX, United States of America

Timothy Otis Weaver