TX 75083-3836 U.S.A., fax 01-972-952-9435. AbstractBranches in Level 1 and 2 lateral extensions traditionally have offered limited access. Coiled tubing (CT) intervention was limited to the main hole only, and thus stimulation of main reservoir targets was not possible.A new system designed with a 2 1/8-in. outside diameter (OD) enables rigless intervention through the completion restriction. The system includes a reentry bottomhole assembly (BHA), which consists of a surface-controlled orienting tool and a controllable bent sub (CBS). The Discovery MLT * multilateral tool identifies the window of the selected lateral before attempting reentry, and confirms successful identification. The entry is visible at the surface through a software-displayed pressure log. The technique does not require a wired coiled tubing string; the corrosion-resistant reentry tool is operated solely by flow and is conveyed with standard CT equipment. As proved by the success of the new reentry tool in Upper Zakum field selective matrix stimulation and nitrogen kickoff operations detailed in this paper, the need to bullhead huge acid treatments that result in major openhole washouts has been eliminated. These washouts can cause both poor acid distribution and prevention of future access to the lateral for CT logging operations. This paper discusses the successful deployment of a selective multilateral entry tool that was utilized to access multilateral wells in Upper Zakum field, two case histories, and the method's potential in Upper Zakum field.The two case studies presented demonstrate the success of this system in reentering a desired lateral on the first attempt for matrix stimulation operations. Current developments that enlarge the scope of application to wellbore logging are under study.

TX 75083-3836 U.S.A., fax 01-972-952-9435. AbstractBranches in Level 1 and 2 lateral extensions traditionally have offered limited access. Coiled tubing (CT) intervention was limited to the main hole only, and thus stimulation of main reservoir targets was not possible.A new system designed with a 2 1/8-in. outside diameter (OD) enables rigless intervention through the completion restriction. The system includes a reentry bottomhole assembly (BHA), which consists of a surface-controlled orienting tool and a controllable bent sub (CBS). The Discovery MLT * multilateral tool identifies the window of the selected lateral before attempting reentry, and confirms successful identification. The entry is visible at the surface through a software-displayed pressure log. The technique does not require a wired coiled tubing string; the corrosion-resistant reentry tool is operated solely by flow and is conveyed with standard CT equipment. As proved by the success of the new reentry tool in Upper Zakum field selective matrix stimulation and nitrogen kickoff operations detailed in this paper, the need to bullhead huge acid treatments that result in major openhole washouts has been eliminated. These washouts can cause both poor acid distribution and prevention of future access to the lateral for CT logging operations. This paper discusses the successful deployment of a selective multilateral entry tool that was utilized to access multilateral wells in Upper Zakum field, two case histories, and the method's potential in Upper Zakum field.The two case studies presented demonstrate the success of this system in reentering a desired lateral on the first attempt for matrix stimulation operations. Current developments that enlarge the scope of application to wellbore logging are under study.