The installation of flowlines in ever-deeper and -more-remote areas requires specific technologies for precommissioning. Coiled tubing can be a solution; however, offshore precommissioning can require coiled tubing to be deployed several times for durations sometimes exceeding a month and requires larger diameters. Therefore, a campaign was initiated to characterize the behavior of coiled tubing under combined plastic and elastic fatigue. In addition, an innovative bend-stiffener design was developed to control the stress levels in the coiled tubing at the hang-off location.
Precommissioning is a critical part of flowline installation and operation. This process occurs at the end of the installation to validate the integrity and performance of any system before commissioning.
When no direct access is available from a surface facility, precommissioning is, most of the time, performed from a multiservice vessel (MSV) using a flexible line. However, as water depth and the diameter and length of the flowline to be precommissioned increase, the submerged weight of the line becomes an issue, requiring the installation of buoyancy modules to limit the loads transferred to the vessel. To simplify offshore precommissioning activities, the company decided to use coiled tubing....
Focus on Ancillary Equipment and Fatigue in Coiled-Tubing Deepwater Commissioning
01 June 2016