Restoration of Adjustable Downhole Flow Control Capability in Deepwater Subsea Intelligent Multi-Zone Completion by Utilizing Electric-Line Stroker as a Linear Vertical Displacement Transducer Deployed via Riserless Intervention Vessel

Multi-Zone intelligent completions normally employ downhole flow control (DHFC) sleeves to selectively produce, isolate or regulate the flow from the individual zones contributing (or injecting) into the wellbore. This selectivity is based on different well management needs not limited to; choking production to manage individual well stock contributions to a facility, isolation of produced water, injection of water into target zone (for injector wells), isolation of one zone to stimulate another, and isolation of lower pressured zones from higher pressures zones to prevent crossflow and inefficient production of the reservoir intervals. This latter reason is also a regulatory requirement in the Gulf of America (GoA) and is the premise of the use of DHFC within the wellbore in question. BP has had long success with DHFC application in producer wells in GoA, albeit most of these DHFC sleeves were simple "on-off" sleeves, i.e. each sleeve only had two positions, fully open or fully closed. However, the DHFC sleeves discussed in this intervention operation were "adjustable" sleeves, i.e. each sleeve could be opened incrementally to regulate flow from its respective zone. This type of sleeve technology is less frequently used by BP for multi-zone intelligent completions, mostly due to little need to regulate individual zonal contributions. Unfortunately, the completion in which these adjustable DHFC sleeves were installed (see Fig. 1) had issues with both the upper zone and lower zone sleeves. The former was suspected to be stuck-closed, the latter was suspected to be partially open and hindered from being fully open, both of these inferences were based on hydraulic pressure signals from the production facility and the observed lack of response from the DHFC sleeves. This paper describes the novel deployment of an electric-line stroker tool as a passive linear vertical displacement transducer (LVDT) to troubleshoot failed DHFC sleeves installed in an intelligent multi-zone completion in the deepwater GoA. The LVDT verified effectiveness of hydraulic commands from the production facility via accurate linear-movement measurements of the DHFC sleeves during open and/or close functions, as part of the diagnosing and remediating process.