Overcoming Completion Challenges with Interventionless Devices - Case Histories Of The 'Disappearing Plug'

摘要

The ongoing need for greater operational cost efficiency hasrnencouraged oil companies to seek new methods that canrnsimplify completion processes and reduce the number ofrnrequired well interventions. This focus has resulted in newrnchallenges for engineering/manufacturing and servicerncompanies to develop multi-functional equipment. To meetrnthese challenges, a new generation of completion equipmentrnwith capabilities that would have been considered impossiblernten years ago has been introduced to the oilfield. Thisrnequipment has been designed to not only reduce the number ofrninterventions normally required in traditional completionrnscenarios but also to meet challenges of safety and reliabilityrnthat can surpass the cost of contingency measures should thernproduct fail.rnThe development of one such device, the "disappearingrnplug," which serves as a plugging device for setting arnhydraulic-type packer, will be the focus of this paper. Whenrnrun in with the completion, the tubing will fill automaticallyrnthrough an auto-fill device, and then, will close during one ofrnthe pressure cycles. The fluid-expendable plug materialrndisintegrates on the last pressure cycle, which allows full-tubing-rndrift production and eliminates the need for a slicklinernor coiled-tubing run to retrieve a plugging device as would bernthe case with conventional methods.rnWhile the industry average for successful installation ofrninterventionless devices has still not reached the sought-afterrn100% reliability, when these concepts have been successful,rnthe expected economic job goals have been surpassed. Whenrnsuccessful in offshore, horizontal, and/or high angle wells where slickline or coiled tubing intervention after completionrnis significantly more costly, these interventionlessrntechnologies have proven to be even more beneficial.rnThe paper will discuss development of the plug, some ofrnthe failures that occurred, how these difficulties werernaddressed, and finally, will discuss several recently runrninstallations. These clearly show the extent of the economicrnbenefit that can be realized.rnDisappearing plug technology currently improvesrneconomics by eliminating the need for slickline and coiled-tubingrninterventions in plugging operations. When settingrnhydraulic packers, this not only reduces operating costs butrnalso the risks associated with interventions and plug failures.rnOne of its most significant contributions, however, becomesrnapparent when considering the future trends of the industry —rninterventionless and intelligent well technologies. Therndisappearing plug will undoubtedly play an important role inrnthe actualization of these future well trends.