With the number of subsea wells increasing so has the requirement to be able to provide lower cost through-tubing live well intervention solutions to a number of well servicing problems. Through-tubing operations on subsea wells are routinely being conducted from a variety of vessels such as monohull or smaller semi-submersible vessels through to larger drilling based rig operations. Many times when performing said remedial or abandonment work on subsea wells the conditions can prove to be extremely challenging to both operator and service provider. Many of the older subsea wells have come to the operating company via a variety of mergers and/or acquisitions and may prove to have a limited history. Often the actual conditions and geometry of the wellbore can be unclear until the subsea well is actually re-entered. However, at this point, the intervention vessel is already on station and incurring daily costs to the operator. In this paper we are going to disseminate several case histories, highlighting the technical and economical advantages that have been achieved in subsea well interventions utilizing through-tubing inflatable intervention tools. Apart from the more recognizable feature of being able to be conveyed into the well on either electric wireline or coiled tubing allowing for live well intervention, the often less perceived advantage of the inflatable type packing element is in its ability to be able to be set in a broad range of both diameters and conditions. Having this ability allows for the operator to have on board the vessel the opportunity to cover many different types of scenarios that may be encountered. This philosophy can markedly reduce the amount of tools required on board to cover a multitude of operations minimizing logistical, storage and cost concerns. One of the presented case histories will highlight how a planned operation prior to load out to plug the completion tubular in order to repair a leaking flowline ended up with the same mobilized tool providing a barrier while being set in the actual subsea tree due to the tubing being found to be parted on entering the well.

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