Multilateral Reentry System for Well Surveillance:Design,Implementationand Summary of 40 Jobs Performed in Fields

摘要

Multilateral wells are a popular choice for fields where maximum fixed asset utilization is required.Although Drilling and Intervention(Stimulation)techniques for such wells are mature and reliable,reservoirsurveillance required novel method for lateral access.Such technology was developed and used in morethan 40 wells in Middle East.Summary of experience,description of tools and methods,lessons learnedand vision for further development will be described in this work.In order to be useful for lateral reentry and logging,intervention system should comply with followingminimum requirements:1.Be compatible with logging tools and systems provided by various Service companies and withvarious conveyance methods.2.Operate with logging systems,not equipped with wired through capability.3.Be of slim design so it can be used in variety of completions.4.Be equipped with diagnostics systems to detect laterals and confirm successful entry.All these requirements were implemented in new Multilateral reentry system.Once in field,system wasproven reliable and useful for logging intervention in multilateral wells in various operating conditions.Multilateral reentry system,consisting of motorized bend sub,wireless communication bridge anddiagnostic section was designed,tested and further deployed in field.Within 40 jobs performed it wasoperating in variety of environments(onshore,offshore);open hole and cased hole completions;was runin oil,gas and water wells,in conjunction with most of commonly used logging systems.Although duringmost of jobs conveyance was performed using electric line Coiled Tubing,some of wells were accessedon wireline using Well Tractor technology.The system was proven reliable and practical experience wasgathered for successful operation of this and any other multilateral reentry system to be designed in future.Application of this system allowed to receive important data needed for fields development and allowedoptimization of completion systems in some cases.Although overall application of multilateral interventionsystem was a success,improvement areas were identified in order to increase operational portfolio;and willbe presented in this paper.Recommendations of intervention friendly well design will be shared as well.As unique experience of running Multilateral reentry system for logging purpose is described here,withpractical recommendations on well construction,surveillance planning,execution and evaluation,this paperwill be interesting to wide category of practicing engineers of various specialties.