Every field development faces the challenge of keeping capital and operational expenditures (CAPEX andOPEX) within reasonable limits, while at the same time exploring matured or new technology that canachieve cost limit objectives. With the uncertainties, cyclic nature, instability in the oil and gas global investment markets, and thefluctuation in crude oil pricing, operators in energy exploration and production (E&P) industries as well asservice providers are constantly looking for better and more efficient cost-saving products and services. Thechallenge of maximizing hydrocarbon recovery in deepwater completions with minimum investment, whilemaintaining the highest level of health, safety, and environment (HSE) and service quality is a continualcatalyst for new products and service delivery techniques. In the operator’s Bonga subsea field, the conventional completions techniques for all open holestandalone screen (SAS) completion installations are performed in multiple trips. The first trip involvesrunning the lower completion including a gravel pack packer with screen assembly which allows a gravelpack packer service tool and an internal string with a pump-thru wash-down capability to enable toe-heel circulation, packer setting, and testing. The internal string, which is comprised of the packer settingtool, internal wash pipe, and accessories, is recovered after completion of the first trip into the open holereservoir section. The second trip involves running the production tubing, production packer, downholegauge mandrel, safety valve, and other completions accessories and landing the production string into thelower completion and on the tubing hanger. The major objectives and drivers for the innovative open hole single trip stand-alone screen completion(STC-SAS) in a deep offshore environment is basically to save rig costs, use proven and emergingtechnologies, employ completions best practices, reduce exposure of personnel to safety hazards, and reducenon-productive times (NPT). New completions techniques with different services and product providerscould pose a challenge in terms of vendor interface management, equipment compatibility, and proceduralintegration of multiple downhole tools with different operating boundaries and limits. The STC-SAS completions concept in deep water was generated with the operator’s Wells Front EndCompletion and Well Intervention team in December 2015. This was driven by an opportunity to furtherreduce well delivery rig time which is at a premium in deepwater subsea completions. The averagecompletions time in the field stood at 10 days per 10,000 ft well. The group was challenged to furtherimprove the well delivery time. However, there was no benchmark as the industry data showed that asingle trip open hole stand-alone screen completion had not been installed globally in a deep water subseaenvironment. This paper presents the evolution of the completions design, the critical challenges in the servicecompanies management, downhole equipment interfaces, operational steps, risks, and the lessons learnedduring the job execution that led to the successful installation of the industry’s first single trip open holesandface STC-SAS in a deep water environment.
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