Over the last decade, the oil and gas industry has continued expanding exploration and production activities into deep and ultra deep waters worldwide.
Production of these deepwater fields is greatly dependent on subsea pipelines and failure of a pipeline can lead to loss of production and, in the worst case, can cause pollution.
Diverless deepwater pipeline repair systems have been developed in order to be able to intervene rapidly and efficiently in case of severe pipeline damage. Some of this repair equipment has been deployed offshore following major pipeline failures.
The successful subsea repairs confirmed the suitability and reliability of the equipment and, moreover, ‘lessons learned’ allowed the development of more compact repair solutions.
Innovative engineering led to the utilization of diverless pipeline repair equipment for a construction purpose since there was no existing technology readily available. For this particular case, significant cost savings could be achieved when the export pipeline of a new deepwater field could be connected to an existing producing pipeline nearby instead of constructing a long pipeline to shore. A combination of proven diverless pipeline repair and standard subsea construction equipment is used to accomplish the goal.
This paper will describe the achievements that are made in deepwater diverless pipeline repair technology, will address specific repair cases, lessons learned and will develop the actual case where for the first time diverless pipeline repair equipment combined with standard subsea construction equipment was used for connecting, in a diverless manner, a new deepwater pipeline onto an existing producing pipeline.