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An offshore operator in Malaysia had run a completion string in a highly deviated 7-in. gas well. When continuous pressure build-up in the production casing annulus was observed during well clean-up, leakage in the completion system was suspected. After several attempts to mitigate the pressure build-up failed, the operator initiated further investigation, which confirmed the suspicion. Small tubing leaks that were allowing produced gas inside the tubing to seep through to the annulus were found. These leaks could have allowed the pressure to increase, and possibly, could have caused the casing to collapse. In order to produce through the annulus, the pressure would have to be vented. With the high demand of gas in Malaysia and since the rig was still at the location, the project team decided to initiate immediate recompletion of the project instead of waiting for a later intervention. This well is one of three wells completed to develop the FN field within KCL area, located approximately 200 km offshore from Bintulu. The field was expected to deliver up to 100mmscf/day per well to help relieve an anticipated gas shortage. This paper discusses the history of the wells, the diagnostic methods used to analyze the well problems, the pros and cons of each solution considered, details regarding the recompletion chosen, and the challenges encountered during the recompletion activities. The discussion also highlights the successful solution used for closing and reopening the fluid loss isolation barrier valve (FLIBV) with a wireline tractor rather than with other options considered after conducting a successful system integration test (SIT) prior to the project execution. The unique solution chosen was a first for Malaysia, and probably, for the world. The success of the recompletion results provided improvements for future applications and will be a benchmark solution for future operations.

Abstract The demand for high capacity production in deep wells has increased interest inthe monobore concept, and thus, when an anticipated gas shortage was expectedin East Malaysia, this concept was considered as a possible strategy for afield in Malaysia which consists of a 3-well development. The targeted area, located approximately 200 km offshore from Bintulu, is expected to deliver100mmscf/day of gas to the Malaysian Liquified Natural Gas (MLNG) plants atBintulu, East Malaysia. New technology such as a tubing hanger profile, fluid-loss device, and glassreinforced epoxy (GRE) completion for large-bore wells and their firstapplication in this country will be presented along with the well requirements, work-over operations, and the innovative solution design developed. Details regarding the completion design, prior development, pre-job planning, asystem-integration test (SIT), operational challenges, and post-job discussionsconcerning the successful completion of these wells will be discussed, as thistype of completion was a first for Malaysia. The findings from the extensive development of the best solution for operationsand the challenges of the project cost objectives will be used to providelessons and improvements for future applications. Introduction The field developments consist of 10 new fields that will be developed in twophases. The first phase consists of 3 of the fields. The second phase consistsof 7 wells in each field, and these will be completed two to three years afterthe first field campaign. The second phase completion design will be based onthe design review and the lessons learned from the initial development. In each field, the first phase will be developed using 3 separate techniquesthat have been identified for each field. The wells have been chosen to bedeveloped as single monobore completions, whereas the other two fields will bedeveloped as openhole sand-control completions and subsea completions. Eachtechnique was chosen to be part of the Petronas long-term vision to train thelocal project team with new technologies and prepare them with basic guidelinesfor the second phase field development. Although all of these completiontechniques have been installed in other regions by other major oil operators, they were new concepts for the project team, and therefore, would provide newcompletion experience.

Many small oilfields in poorly sorted and highly non-uniform unconsolidated formations with high fines content cannot be developed economically using the preferred sand control method, gravel pack. ‘J’ Field in Malaysia is a small oilfield with marginal economics that was developed successfully using stand-alone screen (SAS), a cost-effective open hole (OH) sand control method. Deployment of SAS in ‘J’ Field does not meet the industry-accepted criteria for sand control methods but provided the operator adequate sand control while fulfilling its economic needs. Recent advances in OH sandface completion technologies such as multi-layer mesh screens, inflow control devices (ICDs), and zonal isolation using swellable packers provided improved performance and reliability of recent SAS installations. This project marks a few firsts in sand control screen technology: World's first installation of multi-layer mesh screenMulti-layer mesh screen is the current state-of-the-art in premium mesh screen technology. It uses several layers of woven metal mesh filters of gradually decreasing micron rating and diffusion-bonded together, which creates a filter that provides better plugging resistance and solids retention capacity.Malaysia's first installation of tube-type ICDICDs are passive flow control devices that are used in OH horizontal (Hz) wells to delay the onset of water breakthrough and minimize its effect by balancing inflow from toe to heel or between high-perm and low-perm zones. ICDs are integrated with sand control screens for use in unconsolidated formations. Swellable packers are used in ICD completions to provide compartmentalization. This paper highlights the recent success of utilization of these cost-effective OH sandface completion technologies in the development of ‘J’ Field.

As part of the second stage development of a mature oil field offshore Malaysia, deeper reservoirs in Field S were identified from four different blocks. In order for the wells to be economically viable, up to eleven (11) sands were planned to be completed. This proved to be challenging due to the high differential pressures between reservoirs, highly depleted zones above the target sands, and pressure and reserve uncertainties of the target sands. This paper covers design, planning, and execution of the well completion for four (4) infill wells where the differential pressure between zones was predicted to be up to 1,700 psi (Pounds per Square Inch). Some of the zones were highly depleted, and the most depleted zone was 0.216 psi/ft (Pounds per Square Inch per Foot). Even with the lowest brine weight of 8.5 ppg (Pounds per Gallon), the over balance was about 1,800 psi. The completion was designed to maximize the number of sands in each well (eleven (11) sands with six (6) zones) to gain maximum production, while at the same time the short string needs selectivity. One of the challenges was the production casing design could not be larger than 7". To facilitate selectivity on the short string, the upper completion was designed with a Y-block. To avoid significant losses from high overbalance and differential pressures, stage-by-stage perforation was planned. However, the challenge was to achieve the required under balance across all the zones since there was no stimulation planned. Both static and dynamic under balance perforation techniques were used for perforation. With all the upfront planning and design, the well completion operation was successfully executed with less than 1% Non Productive Time (NPT) recorded, which was an excellent achievement considering the complexity of the completion design and operation. In conclusion, the post-analysis showed the production rate target was successfully attained - indicating the formation damage was minimal even though the wells were drilled and completed with more than 1,000 psi overbalance.