Performance Analysis of Through Tubing Sand Screen Application in Offshore East Malaysia

Abstract

Abstract Through Tubing Sand Screen (TTSS) is routinely used as a remedial sand control solution by the Operator to mitigate sand production in offshore wells located in East Malaysia. A smaller outer diameter (OD) wire-wrap or premium mesh screen is retrofitted inside or set at the end of an existing tubing to filter sand coming from failed primary sand control zone or when there is no sand control installed. The solution has been adopted extensively to mitigate sand production from existing wells as a low-cost application with relatively simpler installation and retrieval operation via slickline, consequently allows for fast reactivation of sand producing wells. Given the large number of installations carried out by the Operator yearly, and most of them recurring in nature, a study is conducted on the past TTSS installations to understand the performance and develop a workflow for design and operation with the aim of improving future installations. This study is done by analyzing past TTSS installations and the associated production performance including sand production parameter i.e. sand count. Parameters such as screen type, length, opening size and installation depth are studied to evaluate the impact to the production performance and the screen service life. Wells with premature TTSS failure are selected for detailed teardown study, whereby the retrieved TTSS joints are sent to workshop to be cut and analyzed for failure mechanisms such as erosion and plugging. Outcome of the study includes a workflow that addresses the main design and operation consideration for TTSS installation capturing the best practices of past installations. Additionally, the study is used to develop strategy for TTSS installations including the required changeout frequency based on the lifespan and inventory management. The paper describes a study on the TTSS performance analysis including selected case studies and teardown analysis. Also, workflow on TTSS design, selection and installation will be discussed.