We present a new perforating technology based on new wireline conveyance equipment and advanced downhole modeling to maximize operational efficiency in long pay-zones under all pressure conditions. Results of perforating jobs of long pay-zones carried out on wireline in very short times compete with traditional Tubing Conveyed Perforation (TCP) operations which take much more time. Also, perforating jobs with large gun sizes that until recently were not possible in a single run with traditional wireline conveyance, are now efficiently executed in a single run. The new technology that allows conveying long lengths of perforating guns on wireline in a single run is based on four main elements: wireline systems with safe working loads up to 30,000 lbf, cutting-edge shock resistant mechanical weak points and disconnect systems, conveyance modeling, and an advanced transient dynamic modeling for perforating shock prediction. The perforating job design modeling is based on the reservoir zones and completion information, both a conveyance and a wellbore dynamics and shock simulation are carried out to determine the highest payload that can be more safely deployed per wireline run, and with the number of runs required, costs and risks are compared between wireline and TCP shoot and pull operations. For a well with a 750 ft thick pay zone, a North Sea operator requested a comparison between this new wireline perforating technology and conventional electric wireline deployment in terms of reservoir productivity, risks, and operational performance. For this well TCP was not considered due to reservoir and operational risks and challenges. Compared to the conventional electric wireline conveyance this new perforating technology offers better efficiency with only two wireline runs using a cable with 18,000 lbf of safe working load and a 10 Kpsi surface pressure control equipment compared to 6 to 8 conventional runs. The longest run consisted of 388 ft of 3 3/8″ guns, which was a new world record on wireline, with energetic liner charges and dynamic underbalance to ensure maximum perforation tunnel cleanup and well productivity. The total operational time for the perforating job was significantly less than conventional electric wireline, which translated into significant rig time savings. This paper demonstrates how the application of innovative technologies have minimized the risks of wireline conveyance with long and heavy perforating gun strings. We utilized well and reservoir information to design a more safe and reliable job execution, including prediction of perforating shock, tension profiles and wellbore dynamics. The new perforating technologies described in this paper have extended considerably the range of perforating jobs where wireline conveyance can be more efficient than traditional coiled tubing and tubing conveyed perforating.

The Raudhatain Zubair reservoir play a key role in the production development plan for North Kuwait. The Zubair production is contributing 20% of total north Kuwait production. Well RA-XX3in North Kuwait Raudhatain field, produced a significantly higher oil rate than existing wells in the field. Production was the application of the latest perforating technologies comprising of deep penetrating charges along with the unique Perforating for Ultimate Reservoir Exploitation and Dynamic Under balance (DUB). The charge used is the deepest penetrating charge available in the industry today, based on API-19B section 1, with penetration depth of 65.2″. Prior existing wells produced an average of 1500 BOPD. This well after being perforated using Dynamic Under balance (DUB) and deep penetrating charges produced 3000 BOPD with zero water cut. The interval perforated was in a high deviated well where traditionally a Tubing Conveyed Perforation (TCP) deployment would have been used to convey guns with a static under balance, correlating the gun positioning with a RA marker more than 2000 ft above the interval. Using the wire line tractor, the guns were positioned accurately on depth, utilizing DUB technology, with significant rig time saving over the conventional TCP runs. A further three wells have been shot using this conveyance method and has shown to provide significant rig time saving with additional production due to DUB technique and accuracy of gun positioning. This SPE paper and presentation will demonstrate the effectiveness and efficiency of deploying guns using WL tractor and benefits of DUB perforating. This successful operation has provided a new approach to underbalanced perforating on tractor to achieve clean, zero-skin perforations is replacing the prevailing underbalanced concept of perforating job design.