RIASSUNTO
Abstract
Rigid jumpers are typically used to provide fluid conduit between different subsea equipment, and are an important part of the subsea oil and gas field development. Although numerous rigid jumpers have been successfully designed and installed, rigid jumper design for corrosive hydrocarbon flow could still be challenging, especially under constraints such as requirements from corrosion resistance alloy (CRA) liner. This paper presents the design considerations and installation techniques applied to PY35–2/35–1 project jumper design and installation in South China sea in 300m water depth. First, the jumper design criteria were described. A total of 11 rigid jumpers with sizes ranging from 4" to 10" were considered in this project. The maximum design pressures are slightly less than 4000psi, and are different for each jumper based on flow assurance data. Second, the jumper constructability was assessed, and constraints were identified due to CRA liner requirement, especially for the 4" jumpers. External coating also imposes limitations to the design. Third, jumper design and analysis results were summarized on both installation and in-place conditions. To facilitate offshore installation, two different jumper lifting options were selected. The base option is to use a jumper installation frame (JIF), which can support up to two jumpers on each frame. The second option is conventional lifting through running tools (CVCRT). Fourth, the jumper installation procedures, and lessons learnt from offshore installation are presented. Experience on the jumper installation sequence constraints was discussed, as well as technical assessment carried out to verify one of the jumper's integrity after having been locked on the wrong hubs. Finally, conclusions were drawn. It was found that the jumper constructability and installability should be adequately considered in early design phase to minimize the design cycles, and jumper design robustness should also be checked to quantify and mitigate the project risks. In summary, all jumpers have been installed successfully offshore, and some of the relevant techniques and experiences are summarized and discussed in this paper.