Published: 04/05/2011
Published: 04/05/2011
Operations in the Gulf of Mexico (GOM) are affected during the months of June through November by the weather, as hurricanes are generated and come into the GOM, creating the need to plan abandonments to avoid harm to any personnel, environment and minimize damage to facilities. During June 2010, while executing a scale clean out operation on a platform with 1.25 coiled tubing (CT), the pipe got stuck. After 11 days of troubleshooting, it was required to evacuate the platform due to a hurricane that was approaching. A management of change was developed to safely secure the CT string at surface, which would allow for abandonment while maintaining well control (WC). During this process three options were analyzed: the first option was to add additional support to the injector head(IH) jacking frame and leave the pipe stabbed in, this option was rejected because it would not guarantee WC in the event that the storm takes down the IH. The second option was to secure the CT with the Blow Out Preventers(BOP) then shear it, and rig down the IH. This Approach provided WC, but it created additional risk and limitations when resuming the retrieval operation after the storm. The third option was to secure the CT at the BOP and cut it above the IH. With the removal of the IH, this would leave the section of pipe that was previously across the chains and riser free above the BOP. An appropriate valve would then be connected to the CT stub end, for WC. Furthermore, by sliding a riser section over the CT stub and making up a gate valve and night cap would minimize the exposure to the storm. Finally, the riser could be secured to the deck. After analyzing available options, the third alternative was recommended and approved by the BOEMRE; as this option addressed WC and allowed safe recovery by re-stabbing the pipe back into the IH, and rigging up the required equipment to proceed with the pipe recovery operation.