Collaboration combats sand control failures Article featured in Harts E&P Magazine   In mature basins, sand issues can account for up to 10% of all shut-in wells either due to failure of the existing downhole sand control or onset of sand production due to pressure depletion and/or water production.   There are many reasons for sand or fine material entering and accumulating in the wellbore, and depending on the level of severity, the consequences need not be detrimental. However, the accumulation of sand production downhole or in surface equipment can lead to production being killed, wells shut-in, or collapse of the formation.   As an inherent problem in the oil and gas industry, the first indication of sand issues downhole will often be as a result of detrimental effects that can occur at surface, such as fill in separators or erosional damage to pipe work.   As existing solutions have been extremely limited due to their high cost and/or poor performance, together, independent global completions service company Tendeka and diagnostic specialists TGT have created Sandbar to mitigate the costly consequences of sand control failure in wells. Downhole monitoring and remediation The conventional process of thru-tubing sand control can be costly and time consuming. In many cases there is a requirement to remove sand from the wellbore prior to installing the chosen sand control solution. Once installed many traditional remediation techniques still allow the wellbore to refill with formation sand reducing productivity and increasing susceptibility to erosional failure.   Therefore, the major challenge is to regain sand control in existing completions and prevent sand from filling the wellbore, without the requirement to perform a workover or complex thru-tubing gravel packs.   Proper diagnosis is the critical first step to any kind of well remediation planning and execution. But determining the precise location and extent of sand ingress downhole has challenged the industry for decades, as previous attempts were unable to reliably distinguish between sand and fluid flow.   The challenge of locating and effectively mitigating sand production has now been addressed by combining the features of two products, one to accurately identify the locations of sand ingress within the wellbore, and the other to quickly repair the damage. The conventional process of thru-tubing sand control can be costly and time consuming. In many cases there is a requirement to remove sand from the wellbore prior to installing the chosen sand control solution. Once installed many traditional remediation techniques still allow the wellbore to refill with formation sand reducing productivity and increasing susceptibility to erosional failure.   Therefore, the major challenge is to regain sand control in existing completions and prevent sand from filling the wellbore, without the requirement to perform a workover or complex thru-tubing gravel packs.   Proper diagnosis is the critical first step to any kind of well remediation planning and execution. But determining the precise location and extent of sand ingress downhole has challenged the industry for decades, as previous attempts were unable to reliably distinguish between sand and fluid flow.   The challenge of locating and effectively mitigating sand production has now been addressed by combining the features of two products, one to accurately identify the locations of sand ingress within the wellbore, and the other to quickly repair the damage. Accurately eliminating sand issues Managing and curtailing sand production issues is essential to maintain asset integrity and extend the life of the asset. Tendeka and TGT have joined forces to create the more effective, intervention-based solution, ‘Find Fix Confirm’ sand remediation service, which is believed to be the first specialized, integrated approach to fully understand and fix sand production issues.   First, the ‘Find’ element of the solution, whereby TGT’s ‘Sand Flow’ diagnostics precisely locates sand entry to the wellbore and provides a qualitative sand count, clearly identifying problem zones, even in turbulent flow conditions (Figure 1). Figure 1: TGT’s Anechoic Chamber completely absorbs reflections of sound and electromagnetic waves, enhancing the company’s acoustic diagnostic capabilities Although commonly used to diagnose a known sand production issue, Sand Flow is also used proactively to ensure downhole sand control measures are working correctly. This can include targeting unconsolidated formation that requires regular intervention, sand screen failure, and surface equipment failure.   Sand Flow diagnostics are delivered using TGT’s ‘True Flow’ system and ‘Chorus’ acoustic sensing platform. Fluids travelling through the well system produce a rich spectrum of acoustic energy, and Chorus captures and decodes the acoustic signature generated by sand particles entering the wellbore. Deployed in hole on wireline, Chorus reveals sand ingress locations and sand count by analysing the acoustic power spectrum of acquired data, and discriminating between sand flow and fluid flow. By flowing from the reservoir whilst the tool is in the well, the acoustic signature of any sand within the production stream can be characterized such that the sand entry points and sand rate can be identified. Chorus leverages high-fidelity recording across a wide dynamic range and proprietary sand-recognition analysis to deliver robust sand detection in a broad range of sand flow scenarios.   To ‘Fix’ or regain sand control in existing completions and prevent sand from filling the wellbore, Tendeka’s one-trip, thru-tubing sand control system ‘Filtrex’, is deployed via coiled tubing into the well and positioned across the target area to quickly repair the breach or damage (Figure 2).   Figure 2: Sand clean out and screen installation by Filtrex is performed across three key stages As a retrievable thru-tubing system, the flexible, open cell matrix polymer filter can be easily installed by conventional means in a live well, this includes thru-tubing, and through tight nipple restrictions.   When self-centralized, it can expand in deviations up to 90˚ and is understood to be the only product of its kind that can be run through larger casing/liner configurations, for example, a 3.688-in. nipple and set in a 7-in. liner. It can be deployed in-hole compressed within the running tool and compression sleeve. This offers full compliance to the damaged section once set. By dropping a ball from surface, a simple two-stage application of pressure firstly sets the anchor, and secondly releases the compression sleeve.   Upon removal of the sleeve, the matrix polymer expands to contact the wellbore and the deployment string can be retrieved from the well. Filling the annular gap with the open cell matrix polymer prevents further ingress of formation solids into the wellbore whilst still allowing passage of liquids or gases. The multilayer system ensures full expansion in the damaged screen section or casing and effective flow divergence regaining sand control in existing completions (Figure 3).     Figure 3: Filtrex expanding out of compression sleeve The first of its kind, the device can perform sand clean out and chemical treatments during live well deployment, thereby preventing multiple intervention trips. When deployed on coiled tubing the installation of the system has the potential to significantly improve the financial feasibility of restoring production to failed wells. As it negates the need for a workover or complex thru-tubing gravel packs, the remedial system can also cut intervention timings and associated run changes by at least half.   The length can be modified to suit the application and lubricator length restriction. If longer lengths are required these can be stacked on top the previous screen section. The system design allows the combination of many distinct layers with a range of cell sizes. This ensures the design has the flexibility to size the screening for each application to ensure appropriate retention of sand in reservoirs up to 110°C (230°F).   Finally and crucially, the service can ‘Confirm’ the effectiveness of the solution with the redeployment of TGT’s Sand Flow diagnostics through the internal diameter of the Filtrex system to confirm that no sand is entering at that depth. This enables better use of resources and more reliable sand control outcomes.   Innovation through partnership As a single approach, existing remedial methodologies to address sand management, such as running an insert sand screen, applying consolidation treatment or performing a remedial gravel pack, are disjointed, lack insight on the precise location of the problem, and often fail to fully eliminate the problem. Likewise, their use can vary in complexity, cost, risk, longevity and effectiveness. Associated weaknesses can often result in reduced production or in extreme cases, loss of surface containment due to erosion.   Bringing together two technologies in one service offering will ensure fast, accurate and tailored remediation to a variety of sand control issues at a fraction of the time, cost and risk of conventional solutions to this age-old problem. Being compatible with thru-tubing operations, including live well deployment and single trip sand clean out, provides greater flexibility and assurance.   Ultimately, it will empower operators to better understand the true sources of sand production and its behaviour and ensure reservoir management decisions are precisely targeted for improved integrity and enhanced asset life.

Dubai, 8 September 2020 - Independent global completions service company Tendeka and diagnostic specialists TGT have agreed a partnership to mitigate the costly consequences of sand control failure in wells.   The remedial sand control collaboration known as ‘Find Fix Confirm’, will see TGT’s Sand Flow product used to accurately identify the locations of sand ingress within the wellbore. Then, Tendeka’s Filtrex  thru-tubing sand control system is precisely situated to quickly repair the damage. Crucially, the service can confirm the effectiveness of the solution with the redeployment of TGT’s diagnostic product.   In mature basins, sand issues can account for up to 10% of all shut-in wells either due to failure of the existing downhole sand control or onset of sand production due to pressure depletion and/or water production.   Launched in 2019, Tendeka’s Filtrex solution is a one-trip remedial system enabling sand-free production to be restored effectively and efficiently. It is fully compatible with thru-tubing operations, even through the tightest of restrictions. The first of its kind, Filtrex can perform sand clean out and chemical treatments during live well deployment.   TGT’s Sand Flow product precisely locates sand entry to the wellbore and provides a qualitative sand count, clearly identifying problem zones, even in turbulent flow conditions. Delivered by the ‘True Flow’ system with ‘Chorus’ acoustic technology, Sand Flow provides the clarity and insight needed to manage sand production more effectively. Although commonly used to diagnose a known sand production issue, it is also used proactively to ensure downhole sand control measures are working correctly.   Paul Lynch, Advanced Completions Director at Tendeka said: “The management and control of sand production is an inherent problem in the oil and gas industry. Often, the first indication of sand issues downhole will be as a result of detrimental effects that can occur at surface, such as fill in separators or erosional damage to pipe work, ultimately resulting in a shut-in well. Existing solutions have been extremely limited due to their high cost and/or poor performance.   “Our Find Fix Confirm sand remediation service addresses both issues to offer a more effective, intervention-based solution. We believe this is the first time a specialized, integrated tool can fully understand and fix sand production issues, to ultimately maintain asset integrity and extend the product life of the asset. We are already seeing significant interest from operators around the world.”   Ken Feather, Chief Marketing Officer at TGT commented: “Proper diagnosis is the critical first step to any kind of well remediation planning and execution. But determining the precise location and extent of sand ingress downhole has challenged the industry for decades, as previous attempts were unable to reliably distinguish between sand and fluid flow.   “Our Sand Flow diagnostics are powered by Chorus technology which captures and decodes the acoustic signature generated by sand particles entering the wellbore to reveal sand ingress locations and sand count. Equipped with that information, Filtrex can be targeted to repair the breach, then Chorus can be deployed again to confirm that the breach is fixed. Overall, Find Fix Confirm enables better use of resources and more reliable sand control outcomes.”   The ‘Find’ element of the solution will see TGT’s Chorus acoustic sensing platform deployed in hole on wireline to pinpoint sand entry locations utilizing time-domain analysis. By flowing from the reservoir whilst the tool is in the well, the acoustic signature of any sand within the production stream can be characterized such that the sand entry points, particle size and volume can be identified.   The ‘Fix’ aspect will see Filtrex deployed via coiled tubing into the well and positioned across the target area. By dropping a ball from surface, a simple two stage application of pressure firstly sets the anchor, and secondly releases the compression sleeve. Upon removal of the sleeve the matrix polymer expands to contact the wellbore and the deployment string can be retrieved from the well. Filling the annular gap with the open cell matrix polymer prevents further ingress of formation solids into the wellbore whilst still allowing passage of liquids or gases.   Lastly, is the ‘Confirm’ stage. Here, the Chorus tool is deployed again but this time passed through the internal diameter of the Filtrex system to confirm that no sand is entering at that depth.