When a well is abandoned the flow line contains well effluent which must be recovered before abandonment is completed -this can present problems, especially in deepwater sub sea wells. In a well in the Campos Basin, Offshore Brazil, in a water depth of 624 meters (2067 ft.), pigs were pumped from the wellhead to the production facility to flush the flexible line, however they became stuck leaving some 1400 meters (4593 ft.) of 4 inch ID flow line filled with production fluid. To clean the balance of the flow line it was decided to cut the line downstream of the pigs and insert a flexible deployment flow line from surface to seal inside the cut and thereby facilitate the continued displacement of the flow line. It was agreed that the use of an inflatable packer deployed by a Remote Operating Vehicle (ROV) would offer the best chance of success, however two problems existed which could affect the adequate sealing of the packer element:

• The ID of the flexible flow line contained a continuous spiral groove 1/16inch deep.

• The sea floor temperature at the mud line was 39°F.

To evaluate this, lab tests were initiated and successfully performed to confirm viability of the seal in this situation. The packer was then made up with a 1″ hose to a 4″ ID flexible deployment line located on a work barge, run to bottom and inserted into the flow line cut using the ROV. It was set, the setting plug sheared and 862bbls of sea water were pumped through the line to clean it out. Upon completion of the job the packer was left in place and recovered along with the flow line.

In this paper the authors will describe the testing of the concept, its subsequent successful use with the ROV and the problems which were encountered with inserting the packer into the flow line. They will go on to describe two further such operations in which the lessons learned from the first operation were taken into account. All the operations were successful, allowing recovery and subsequent reuse of the flow lines.

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