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This paper was also presented as SPE 68762 at the 2001 SPE Asia Pacific Oil and Gas Conference and Exhibition, 17–19 April, Jakarta, Indonesia. Abstract This paper will describe the first coiled-tubing-conveyed perforating (CTCP) jobs performed offshore in a horizontal well in the Campos Basin, Rio de Janeiro, Brazil. The operation was needed to obtain the objectives sought after for this well and also to provide a "learning curve" for a major job that was to be run subsequent to this job using the same method. The second job was to be in a water depth of 968 ft., and more than 1,000 ft. of guns would be run. Both jobs will be discussed in this paper along with the advantages gained on the second job from the first experience. The first procedure required perforating of a 262-ft. interval in a 92-degree horizontal well using 2 in., 6 SPF super deep penetration scalloped guns that would be coiled-tubing deployed through 3–1/2 in. production tubing. The operation was to be performed from a semi-submersible platform, and the running and retrieving of the perforating guns would have to be accomplished without killing the well so that damaging completion fluids would not come into contact with the reservoir. Requirements for the job were that a safe method be used and that equipment and operational costs be kept at minimum so that a greater return on investment could be realized. Operational conditions included the following:Perforation was ato be conducted with the well in an underbalanced condition so that no formation damage would be sustained.The operation had to be run from a semi-submersible 5that was set in a water depth of 430 ft. (2nd job performed in a water depth of 968 ft.)The gun assembly would have to pass through a 2.81-in. minimum ID. He two jobs were completed under live well conditions, and both were successful. The estimated cost saving from elimination of 3 days of rig time for the second job was approximately $360,000. Even more significant for this technology, there are no documented jobs in which this perforation length has been attempted anywhere in the world from a semi-submersible or where the water-depth distance was used as a lubricator for the guns. Introduction Coiled tubing has been used for several years to deploy perforating guns, and this technology has enabled many operators to use the latest techniques to complete high-angle wells with optimum completion designs. Until recently, however, this perforating method was not used in Brazil because of the complexity and risks involved, particularly on offshore platforms (semi-submersible rigs and/or drill ships) where daily costs are extremely high. For twenty years, Petrobras has been developing state-of-the-art technology for deepwater environments in order to determine best practices to realize the most efficient production. From the time of its first oil production in 1977, the Campos Basin, located off the northern part of the state of Rio de Janeiro has been proving its potential as a major oil-producing province. Already responsible for three-quarters of the country's production, Campos is by far the main production area in Brazil. During those twenty years, 66 fields have been discovered, and exploration and drilling operations are ongoing. (See Fig. 1) This paper will cover two CTCP jobs that were performed in the Moreia and Albacora Fields. The Moreia Field, in which the first job was performed, reaches water depths of 430 ft, and the Albacora Field, where the second job was performed (because of the success of the Moreia job), reaches water depths of ± 1000 ft. The jobs were performed from a semi-submersible platform. (See Fig. 2)

Coiled tubing has been used to deploy perforating guns for several years, and use of this technology has enabled many operators to complete high-angle wells with optimum completion designs. Until recently, however, this perforating method was not used in Brazil because of the complexity and risks involved, particularly on offshore platforms (semisubmersible rigs and/or drill ships) where daily costs are extremely high. This paper will describe the first experience of coiledtubing-conveyed perforating (CTCP) performed offshore in a horizontal well in this South American country.The first CTCP job was to be performed not only to obtain the well objectives needed for the well but also to be used as a "learning curve" for a major job that was to be run subsequent to this job using the same method. The second job was to be in a water depth of 968 ft. and more than 1,000 ft. of guns would be run. Both jobs will be discussed, along with the advantages gained on the second job from the first experience.The first procedure required perforating of a 262-ft. interval in a 92-degree horizontal well using 2 in., 6 SPF super deep penetration scalloped guns that would be coiled-tubing deployed through 3-½ in. production tubing. The operation was to be performed from a semi-submersible platform, and the running and retrieving of the perforating guns would have to be accomplished without killing the well so that damaging completion fluids would not come into contact with the reservoir. Requirements for the job were that a safe method be used and that equipment and operational costs be kept at minimum so that a greater return on investment could be realized.Operational conditions included the following: 1. Perforation was to be conducted with the well in an underbalanced condition so that no formation damage would be sustained. 2. The operation had to be run from a semi-submersible platform that was set in a water depth of 430 ft. (2 nd job performed in a water depth of 968 ft.) 3. The gun assembly would have to pass through a 2.81-in. minimum ID.