The aims of every oil & gas operator to optimize production, increase oil recovery, and minimize operating cost are driving the industry to look for innovative completion and production solutions. This is true for brownfields where operators are looking to rejuvenate reservoirs that still have reserves in place as original completion efficiencies deteriorated over time. A workover offshore Malaysia was conducted in a field to recover oil from a multilayered, high water/oil contact reservoir. The objective was to increase production and recovery volumes in a cost-effective way and reduce rig time. The original completions lacked the ability to control and choke the flow from each zone independently, and thus could not optimize comingled production and water cut, resulting in limited oil recovery from the reservoir. For this reason, an intelligent completion with downhole variable flow control valves and real-time pressure and temperature gauges was considered. The objective was to design an intelligent completion that is both cost effective in a marginal field and that can fit inside an existing cased-hole wellbore that requires sand control. Because of the many challenges faced in combining the multizone gravel-pack system and the intelligent completion components, both had to be re-engineered to allow for a perfect interface. This resulted in the first intelligent completion installation inside a shunt-tube gravel pack with multizone packers.

The aims of every oil & gas operator to optimize production, increase oil recovery, and minimize operating cost are driving the industry to look for innovative completion and production solutions. This is true for brownfields where operators are looking to rejuvenate reservoirs that still have reserves in place as original completion efficiencies deteriorated over time. A workover and new well offshore Malaysia was conducted in a field to recover oil from a multilayered, high water/oil contact reservoir. The objective was to increase production and recovery volumes in a cost-effective way and reduce rig time. The original completion designs in the field lacked the ability to control and choke the flow from each zone independently, and thus could not optimize comingled production and water cut, resulting in limited oil recovery from the reservoir. For this reason, an intelligent completion with downhole variable flow control valves and real-time pressure and temperature gauges was considered. The objective was to design an intelligent completion that is both cost effective in a marginal field and that can fit inside a cased-hole wellbore that requires sand control. Because of the many challenges faced in combining the multizone gravel-pack system and the intelligent completion components, both had to be re-engineered to allow for a perfect interface. This resulted in the first intelligent completion installation inside a shunt-tube gravel pack with multizone packers and subsequently future wells with same design.

The development of any marginal field is a difficult process when the operator is faced with the challenge of maximizing hydrocarbon recovery with a minimum investment, when at the same time, the highest HSE standards must be achieved. This paper summarizes the challenges faced by an operator in Malaysia, who successfully completed two (2) oil-producer wells in a developmental field using a single-trip stand-alone screen (SAS) completion system. The improved system enabled the operator to save up to 24 hours per well during the completion phase using a jack-up rig, when compared to running conventional dual-trip completions. This system eliminated the need for a liner hanger or gravel-pack packer and mule shoe. It also allowed wash-down capability via a permanent inner string that eliminated extra runs that would have been required using wash pipes in a conventional dual-trip completion. Both wells were selected as candidates for this pilot project based on the guidelines below: Simple completion design Shallow depth < less than 2500 m measured depth drill floor (MDDF) “J-type” wells with low deviation < 450 Short openhole length < less than 500 ft Initial single-target zone. Potential risks identified during the operation were discussed in depth with the complete project team. A service/engineering company's software program that included a comprehensive set of engineering tools for analysis, well planning, modeling, and well-operation optimization was used to simulate the completion string performance in the actual downhole conditions. The simulation results helped determine the risk of undesirable incidents that might occur during the completion installation. This concept was proven later by the successful deployment of the completion string. Packer selection for this type of completion design was also critical. With a wide variety of packers offered in the current market, the completion designer proposed that a specific hydraulic-set retrievable production packer be used. The selected packer provided heavy hang-weight capability with easy installation and retrievability for future work overs. The packer's hydraulic setting mechanism comprised an anti-pre-set system that would prevent the packer from prematurely setting due to friction pressures on the completion tubing during openhole displacement operations. The success of the completion installation on the first well gave the operator enough confidence to apply the same operational approach to a second well that included an additional pay zone, which was isolated using a swellable packer; the second completion was successfully deployed as well. A total of 48 hours, equivalent to 28 percent of rig-time savings, optimized the overall completion efficiency for this campaign. This pilot project will be used as a bench mark for future stand-alone screen applications on wells with similar characteristics.

Smart Auto Gas Lift (AGL) refers to a downhole system that utilizes gas from a gas zone or a gas cap in a well to lift oil below or above the gas zone in the same well. This paper illustrates a novel AGL intelligent completion design approach including candidate screening, pre-drill feasibility study, sensitivity analysis, and followed by the completion installation and production operation practices for the first two (2) successfully completed AGL wells in Malaysia. In the candidate screening process, a novel design approach was used based on a 3D numeric single wellbore dynamic model forecasting method. Firstly, candidate screening was performed for the application suitability of AGL in the candidate reservoir. The key screening factor includes the identification of the source of AGL gas, either from the associated overlaying gas cap or independently from another layer of non-associated gas, estimation of gas pressure and oil pressure, estimation of volume of available AGL gas and longevity of gas reserve throughout oil production life, and considering the reservoir structure and drive mechanism. Secondly, single well prediction modelling analysis was performed to evaluate candidates' dynamic performance on production rate, water cut, gas oil ratio (GOR) profile and pressure depletion over time. This is to make sure designed AGL completion will meet expected various production dynamic responses during the entire life of well. The next step is to conduct production snapshot nodal analysis for the appropriate choke size design for AGL downhole flow control valve. Those dynamic results from the single wellbore prediction model becomes important input for nodal evaluation to simulate changing reservoir conditions at different stages. Finally, various sensitivity analyses on layer properties and valve setting depth are followed to ensure that the AGL valve choke sizing design range is flexible enough to cover expected reservoir uncertainties and to be effective over the entire well life. Based on above design and analysis approaches, a specified range of AGL valve choke opening were designed for T field candidate wells and smart AGL completion system was installed successfully and safely in two wells by end of 2014 without any health, safety and environmental (HSE) issue and AGL related non-productive time (NPT). The production and well test data were available for production performance surveillance, and the dual permanent downhole gauge system (measuring pressure and temperature in both the tubing and the annulus) at gas zone enabled the continuous auto gas injection monitoring at real time basis. This paper discusses AGL well design approaches, justifications, best practices and lessons learned regarding completion installation, well clean up and production operations to give a general guideline for AGL implementation in this area in the future.

This paper summarizes the challenges faced during the well completion design, planning and execution stages in the "Well-B" located on the "Field-A" offshore Malaysia. In addition, it highlights the modifications and techniques incorporated in the completion design to ensure that the well was delivered flawlessly in terms of HSE and quality. At the initial planning stage, the proposal on this well was to complete two oil producer sands with active sand control methods, the upper zone with Cased Hole Gravel Pack (CHGP) and the lower zone with Open Hole Standalone Screens (OHSAS), this concept changed after the analysis of the logging while drilling (LWD) output, when the subsurface team decided to complete an additional zone (midzone) with a stacked Cased Hole Gravel Pack. The well completion operation effectiveness on this well could have been affected by the following challenges: High deviationMultiple sand control techniques in one wellOperation and logistic challengesAdditional zone expected to be completed with the available inventoryLimited resources and time The team incorporated several techniques into the original completion design to enable the effective execution of these three zones and achieving the overall well objective. After the well was successfully completed, it became the first highly deviated well in the field with an open hole standalone screens in the lower zone and two cased hole gravel pack in the upper zones with a dual upper completion string. This well completion will become the benchmark for planning, designing and deploying future wells with similar characteristics and reservoir conditions.