Intelligent completions and electrical submersible pumps (ESPs) are realizing greater oilfield acceptance because of their capabilities to improve recoveries, especially in multi-zone wells where production can be controlled and optimized without intervention. Previously, when ESPs had to be removed for routine maintenance, the whole completion had to be pulled, which would require significant time, risk, and cost. Now, an electrical disconnect tool exists that enables ESPs to be changed out without requiring the lower intelligent completion to be removed. This paper discusses the equipment and methodology recently used in a trial test offshore Brazil to reliably disconnect an ESP in the upper completion from the lower intelligent completion that had two interval-control valves (ICVs) and two dual-sensor pressure/temperature gauges. The trial test required the disconnect sub to be disconnected from the receptacle, then reconnected again, followed by an ICV and gauge function test to prove the reliability of the wet mate connector in the electro-hydraulic disconnect tool.
This paper highlights the successful case history of the new disconnect tool installed in January 2013 in the Carapeba field, offshore Brazil. The paper will discuss the technical aspects of the concept, the well-planning details, completion procedures, installation lessons learned, and tool design improvements that will be adopted for use in future wells.
This installation will initiate the use of electrical disconnect tools for upcoming intelligent completions involving ESPs, sub-surface safety valves, or long horizontal sections that may require the lower completion to be installed on drill pipe.