This paper outlines a general concept and develops a practicalwell surveillance method to monitor and operate sand controlcompletions that optimizes production without introducingextra risk of completion impairment and failure. The generalconcept requires: (a) determining the sand control failurecriteria that the surveillance method should be based on, (b)establishing a direct link between the identified failure criteriaand pressure transient analysis information, and (c) validatingthe surveillance method. The proposed surveillance methodutilizes readily accessible well information without requiringproduction log measurements of down-hole velocities withinthe completion interval.The proposed method is fully developed for cased hole,gravel pack completions assuming the gravel-filledperforations dominate flow within the completion. Theequations are given and velocity criteria are established. Inthis case the two dominant completion failures are screenerosion and destabilization of annular pack. The maximumflowing velocities for these failure mechanisms can beestablished using field production logs, laboratory screenerosion data, and mathematical calculations of fluid flow inthe annulus pack. The pressure drop across the gravel packedperforation tunnel is the dominant completion pressure dropfor the cased-hole gravel pack system. This pressure dropequation is non-linear or proportional to square of perforationflowing velocity.The well surveillance method monitors down-hole flowingvelocity and completion pressure drop to operate the wellwithout introducing unnecessary completion impairment andsand control failure risks. The process of ramping up the welland determining a safe maximum rate goes beyond the strictadherence to absolute values of acceptable completion pressure drop and down-hole velocities and is integrated withprudent surveillance. The method recommends severalpressure transient analyses be taken, at increasing flow rate,during the process of ramping up toward the peak rate, to helpassess and diagnose the performance of the completion. Thisintegrated assessment by direct measurement of completionpressure drop and corresponding calculation of flowingvelocity provides real time feedback of information on theperformance of the completion during the ramp up process.Using this direct and simple process, engineers can customizethe operating guidelines for each well so that less impairedwells can be produced at higher rates and the more impairedor higher risk wells are identified for remedial operations andproduced less aggressively.This paper demonstrates the application of the proposedconcept and surveillance procedure, in reaching the peak rate,for the cased-hole gravel pack completion. Three fieldexamples are provided to illustrate how engineers are able touse standard pressure transient analyses and the proposedsimple method to assess the completion response to eachadditional choke increase and to optimize well productivityduring the ramp up process. This paper summarizes keyfindings on the implementation of this new integratedsurveillance tool.
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