Design of a Two Piece Lifted Jacket for 630 Foot Water Depth

摘要

A new type of jacket design was developed for a Gulf of Mexico platform in 630 feet of water. The jacket was designed for installation in two sections that were joined underwater with a grouted connection. Both jacket sections were lifted from transport barges and installed on location with a Semi-Submersible Construction Vesel. This installation method was used to avoid the typical launch framing required for jackets in this water depth. This launched jacket weight. The jacket fabrication schedule is also reduced due to less steel tonnage. This paper describes the unique features and important aspects of the design, including the design approach, the underwater mating and the splice details. The development of this design concept has added an alternative to conventional single piece launched jackets designs for water depths from 500 to 700 feet. Information provided in this paper will allow designers and planners to evaluate this alternative design concept. Results are presented showing the steel weight savings.