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Ceramics have long held significance as a prime material to humans and today can be found in any industry. This paper discusses the successful application of standalone ceramic screens as an emerging technology solution for well restoration and sand control in Columbus Basin offshore fields. In well sand screens, they are proposed to significantly boost erosional limits and durability, when compared to traditional metallic screens. This hypothesis was tested in oil and high-rate gas wells in highly unconsolidated and low volume reservoirs which were previously shut-in or undeveloped for various reasons. In all cases, development through traditional rig-based sand control techniques would have been uneconomic. This paper presents the job design approach including candidate selection, screen selection, erosion testing, and deployment. Well performance post implementation is also examined. Initial screening for up-hole recomplete candidates showed that a sand control completion was required to access reserves from the unconsolidated reservoirs. Additionally, the proposed reservoir intervals were short and resulted in high flow velocities challenging even traditional sand control techniques such as cased hole gravel packs. Applying a ceramic standalone screen as a solution was based on the building of a natural sand pack to retain the formation sand with screen slot sizing designed to minimize plugging. Various screen slot sizes, geometries and analogous cores were tested in laboratory sand retention tests to retain the largest sand particle sizes and allow a natural sand pack to develop. Interpretation of the results was often challenging due to the wide variabilities in particle size distributions inherent to the nature of the sands being tested – non-uniform, poorly sorted and high fines content. Deployment of the screens was performed rig-less and was further complicated by aged offshore infrastructure with de-rated cranes, limited deck space and compact well bays. Bespoke solutions were developed to allow screen deployment without the use of the platform crane and straddle systems to enable downhole connection of multiple screen sections. Standalone screen designs were developed for failed sand control repairs and newly perforated sections. Start-up of the wells was performed with a bean-up strategy allowing for a stabilized natural sand pack development. Both oil and high-rate gas wells showed similar results with sand free production from the onset with minimal plugging on most applications. This paper will discuss the importance of candidate selection to minimize same. Utilizing job data and flowing measurable parameters, the ceramic screens flow velocity performance was estimated to be between five and ten times greater than those associated with traditional metallic sand screens under the same standalone application. Further laboratory erosion work was also performed to de-risk the flow rate potential of installed ceramic screens, significantly improving understanding of the failure mechanisms of the ceramic screen. This resulted in doubling previous flux velocity thresholds for the screen from 100 ft/s to 200ft/s. The performance of ceramic screens highlights their applicability as a viable sand control technique once properly aligned to expected well performance. It now widens the toolbox of non-rig sand control applications beyond the conventional rule of thumb provides a lower cost alternative to rig completions.

The Dvalin gas field is located in the Norwegian sea on NCS and is operated by Wintershall DEA Norge. It is supported by two independent reservoir structures, Dvalin East and Dvalin West. The field was explored through wells 14S and 15S in 2010 and 2012, respectively. The field is characterized by dry gas, high CO2, high temperature (160 °C) and high pressure (SIWHP 620 bar). The targeted Garn sandstone has good reservoir quality, but with a high permeability contrast. The field development was sanctioned in 2016 and calls for a 4 well solution through a centrally located subsea template, producing gas back to the host platform Heidrun TLP 15 km away. Water depth at location is 380 m and targeted reservoirs are at 4140 m MSL (East) and 4240 m MSL (West). Production plateau rates are estimated to be approximately 106 MMscf/D (3 million std m3/d) per well where thin high-permeability zones within the Garn formation are expected to dominate the inflow. The lateral facies development is thought to be relatively homogenous throughout the field, thus S-shape wells falling off to vertical through the reservoir will ensure effective drainage. Sand failure is expected after short time of production and would increase the risk of erosion causing severe damage to well jewelry and production facilities. It has been decided to integrate sand screens as a means of downhole sand control as part of the primary lower completion design. The sand screens will offer sand control, erosion resistance, hot spotting resistance as well as robustness towards a full hole collapse during reservoir pressure depletion. As the subsea completions are carried out from a mobile drilling unit in harsh environments, protection of the sand control filter media during installation is of utmost importance. This paper will describe the selection process of sand control and qualification steps carried out to use ceramic screens as the stand-alone screen solution for successful deployment and integrity for the Dvalin field development

Formation sand production is one of the major production challenges in most of the mature fields in Malaysia. Often, failure in primary sand control equipment requires the operators to adopt through-tubing sand screens as remedial sand control. Due to the erosion prone nature of the thru-tubing metallic sand screen, operators are forced to impose limitation on the production rate coupled with stringent surface sand monitoring system to avoid surface flow line leakage and loss of primary pressure containment. Therefore, to seek a more robust technology than conventional metallic screens, alternative technology with through-tubing ceramic sand screen (TTCSS) has been considered with the idea of higher durability and resistance against erosion. This paper will discuss the performance and lessons learnt from the application of through-tubing ceramic sand screen throughout several mature fields in Offshore East Malaysia. Over the past two years, there have been about twenty-five TTCSS installations in Offshore East Malaysia. Seven pre-mature failure cases were observed, where sands were produced to the surface and even caused leaks on the flow line. The average effective production period for all TTCSS across all the fields ranges from 6 to 11 months. Teardown investigations have been conducted to diagnose the failure root cause. Most failed TTCSS exhibited similar failure patterns at the end caps, which house the spring compensator. Failure to stop the flow through the end caps led to substantial erosion at spring compensator and base pipe, inducing large flow path for sand production to the surface. Other than the design failure, application failure was observed at the ceramic rings due to their brittleness. Computational fluid dynamic simulation and laboratory testing have been conducted at the higher incremental production rates to support the observations from teardown inspections, refine the hypothesis of failure mechanism and enable an incremental design change to be modified into TTCSS. In order for TTCSS to be one of the competent candidates for remedial sand control, new improved standard design of TTCSS with strengthened end cap area will be studied to prevent similar failure.

As part of the overall Ichthys project there was a requirement to develop a remedial sand control application that would be suitable for installation should the sand production levels exceed the tolerance of the system. After an exhaustive review of available techniques, a remedial insert ceramic sand screen was selected as a potential option for these high rate gas wells. In order to be confident that the screen would be suitable for the application a comprehensive design and qualification plan was developed. Due to the nature of the application and the technology itself the qualification programme was significantly more complex than typical oilfield equipment qualification; many of which can adopt standard API/ISO testing protocols with clear cut pass/fail criteria. A number of specific elements were required to underpin the qualification. Firstly and perhaps most importantly was pre-qualification of the overall strategy itself. This can be thought of as the engineering work to endorse the approach, including the assessment of any inherent risks, and the development of the overarching qualification framework including understanding the dependencies between specific qualification work scopes. Once the strategy was endorsed and the framework developed, a significant amount of time was spent maturing the testing programme and the subsequent pass/fail criteria, often involving extensive discussion with a number of specialised companies and especially the provider of the screen. A thorough and extensive set of modelling and testing was conducted to endorse the final product for the application including fundamental FEA and CFD modelling through more traditional burst/collapse testing, end ring weld certification and corrosion studies to bespoke bending, impact and erosion testing. In addition as this is a new technology and does not conform to any existing sand screen quality plan it was necessary to conduct a joint quality management system audit and screen manufacturing assessment. This led to the construction of an agreed Quality Control Plan; and specific production quality checks to ensure critical requirement conformance of the overall process and end product. The end result was a successfully qualified product for the Ichthys high rate gas remedial application.

Sand production is a common problem throughout the oil and gas industry, particularly in ‘high rate’ gas reservoirs coupled with low rock compressive strength. Conventional downhole sand control techniques such as gravel packing can act to limit both well geometry and/or productivity. Furthermore, problems with gravel pack installations can lead to preferential inflow, leading to ‘hot spotting’ and ultimately loss of sand control. To evaluate the erosion resistance of sand control equipment under the highly erosive environment of high rate gas wells, innovative testing equipment is needed. This paper will discuss the development of a Gas Sand Screen Erosion Test (GSET) rig and its application to evaluate the erosion resistance of ceramic sand screens. GSET is designed to simulate ‘accelerated’ erosive down-hole conditions. The GSET cell can accommodate but not limited to a screen stub section, screen coupons and variety of downhole equipment. A combination of high flow rate gas and volume controlled particle reservoir matched sand is coalesced into an acceleration tube. The high velocity sand particles (>80m·s-1) impact the ceramic sand screen, causing erosion within the target area. In this paper, the GSET rig was operated for 48 hours at maximum velocity (>80m·s-1) and with a sand concentration of 750 ppmw. Take into consideration that the velocities seen throughout this paper are significantly greater than what a conventional reservoir/completion system would have to tolerate. Initial and final sand screen analysis was conducted to evaluate the performance of erosion resistance. An array of analysis techniques was applied with focus on gap aperture size and surface topography. Gap aperture measurements were a focal point, as it is directly proportional to its ability to maintain sand retention capabilities. This paper highlights the potential of the new GSET rig, enabling laboratory testing of erosion resistance of sand control equipment for high rate gas wells under accelerated conditions. Test results obtained with the ceramic sand screen section underpin the inherent high erosion resistance of ceramic sand screen technology ensuring longevity in highly erosive environments. Thus, providing opportunities to complete both new reservoirs and intervene in existing fields with remedial sand control solutions; through extension of the viability of stand-alone screens, simplification of well construction or intervention and increase in productivity. The observations made by the authors are supported by extensive laboratory testing. The resources provided in this paper will allow petroleum engineers to appropriately evaluate the potential benefits of utilizing ceramic sand screen technology in their completions.

This paper will present the first successful application of ceramic sand screen in Malaysia. Oil production from the field has a long history beginning with the first production in 1972. A great number of sand control methods have been tested and applied in the field. Production history has showed instances of sand production contributed by factors such as in-situ stress changes, increase in water production and cascading effect from production operation activities. A few wells completed with primary sand control equipment have failed and remedial action by metallic through tubing sand screen experiencing rapid wear, forcing the operator to control sand production by beaning down the wells and closely monitoring sand production at surface overtime. Worse still, some of the wells had to be closed-in. Hence ceramic sand screen was considered as remedial sand control due to its superior durability and resistance compared to metallic sand screen. This paper incorporates sand retention tests conducted using actual core samples to customize the slot opening/size, impact test conducted using actual ceramic sand screen assemblies in a training well to look closely at the installation mode and tool assemblies, newly-developedinstallationand well unloading procedure as guidance for offshore personnel and actual field result of the wells installed with the ceramic sand screen. Through tubing remedial sand control using ceramic sand screen has successfully revived the idle wells back to production at a lower total cost, oil gain beyond the initial target and higher Return OfInvestment (ROI). It has proven to be a great new technique which enables the effective sand control in highly erosive environment and would openup bigger opportunities to unleash locked-in potential of wells with sand production problem throughout PETRONAS’ operation.