Enhanced Thru-Tubing Ceramic Sand Screen: Performance Review from Pilot Installation in Offshore East Malaysia

Abstract

Abstract Sand production remains as one of the most challenging complications in managing mature fields in Malaysia. More than half of the wells in Malaysian fields are completed with downhole primary sand control or require sand management throughout their lifetime. To further aggravate the issue, most primary sand controls installed have suffered from failure after an extended period of production. Thus, operators are often compelled to rely on thru-tubing metallic sand screens to reactivate idle sand wells. However, most metallic sand screens suffer from sustainability issue due to substantial erosion especially for those installed in wells with high gas flow rate. Therefore, alternative technology such as through-tubing ceramic sand screen (TTCSS) has been considered and applied due to its higher durability and resistance against erosion. This paper will discuss the evolution of TTCSS design and performance improvement in terms of longevity. Field application in Malaysian mature fields has shown that ceramic sand screen demonstrates a longer lifetime when compared to conventional metallic sand screen. However, to further improve the mean time between failures (MTBF) of TTCSS, extensive studies have been conducted by carrying out detailed teardown investigation and computational fluid dynamic (CFD) simulation. Design changes have been proposed and incorporated to mitigate the erosion risk at end cap area based on previous well installation. The enhanced TTCSS were then installed in the same well with high erosional velocity as pilot testing. The operating well envelope and installation method were maintained following the previous installation. TTCSS with enhanced design were then retrieved after a period of three months for detailed evaluation. Several criteria have been identified as key performance indicators for the success of enhanced TTCSS design. Throughout the pilot testing period, sand production at surface has been closely monitored to detect any sand grains larger than screen slot sizing. Upon retrieval, enhanced design of TTCSS shall not exhibit similar erosion patterns at end cap area which will affect the integrity of spring compensator system and cause the screen to lose its filtration mechanism. Lastly, enhanced TTCSS design shall prevent parting of screen during retrieval, reducing the risk of leaving the screen downhole as fish. This paper will present the outcome of pilot testing of enhanced TTCSS by comparing the performance with the original design using both teardown investigation and velocity calculation. Suggestion for further optimization will also be discussed to ensure TTCSS remains as one of the competent candidates for remedial sand control which can offer greater durability and longevity.