Deepwater wells using fracpack stimulation are progressively moving to ultradeep water depths and total depths; the bottomhole pressures (BHPs) and temperatures of future reservoirs could exceed 20,000 psi and 250°F. To safely perform deepwater fracpack treatments, the following pressure and tubular limitations should be considered:• Maximum surface tubing pressure because of pipe limitations and gravel pack assembly component ratings.• Maximum surface annulus pressure because of blowout preventer (BOP) ratings.• Maximum allowable tubing movement while pumping to help prevent premature job cessation.• Maximum allowable downhole slackoff and overpull because of well path, pipe, pipe connections, and downhole component ratings.Depending on the well depth, pressure, temperatures, and BOP type (subsea or dry-tree), various pipe, connection, or equipment limitations might be exceeded during multistage fracpack stimulation operations. Initial pipe loading as well as pre-fracpack stages, such as the pickle, acid treatment, or minifrac calibration treatment, will alter the pipe failure and movement conditions and must be accounted for in the final completion design.Because of these concerns, a workflow process has been delineated to evaluate the maximum allowable treating pressures, tubing movement, and tubular limits for deepwater subsea and dry-tree fracpacks across four components:• Input component to consolidate well and stimulation data for further workflow analysis.• Surface treating pressure evaluation component to analyze certain treating pressure limitations.• Commercial wellbore, casing, and tubing simulator to evaluate work string safety factors, tubing movement, and downhole forces. • Commercial torque and drag simulator to evaluate surface slackoff requirements and allowable work string overpull.A description of the variables, range of values, and other considerations for each of these four components is discussed, and the benefits of using this process to evaluate fracpack stimulation are shown. Well case histories are also used to support this process.

Particle movement is a problematic occurrence for wells producing in the Gulf of Mexico (GOM). The particles could be formation sands or proppant. The most widely used and most effective method of sand control in the GOM is the mechanical method. The mechanical method used in most wells includes the use of screens with a proppant pack. An alternative to the mechanical method is the chemical-consolidation method. With this method, the particles are bonded together to prevent movement. This paper describes chemicals and treatments that can be used to consolidate downhole particles as well as explains scenarios in which these materials can be used.Chemical consolidation has many applications in unconsolidated-reservoir environments. One application is to use this technology to consolidate the formation in the near-wellbore region, which would be suitable as the only form of sand control. Another application would be to use these chemicals for screen repair. When the well is producing proppant and formation sand because of a damaged screen, consolidating the proppant pack around the screens is a proven way to stop the particles from flowing. Both of these techniques involve injecting chemicals into the well. Instead of consolidating with a chemical injection, proppant particles can also be coated with chemicals on the surface during pumping of the proppant-stimulation treatment.The results that can be observed from these treatments demonstrate that produced solids can be eliminated. The production data of wells that have used these chemicals to measure the effectiveness of the treatments were compared. From the data presented, it can be concluded that these treatments provide additional options for completing or repairing wells that require sand control. The data also demonstrates ways to stop solids from being produced with well-intervention treatments.This paper explains a variety of ways that particle-consolidation chemicals can be applied, along with a general description of the materials used. Lab data associated with these chemicals is presented. Use of this technology is discussed in detail, including several case histories in the GOM.

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Deepwater completions are defined as those executed in water depths of greater than 1,500 feet. The extreme depth in itself presents challenges, but in addition to these, operators are continuing to seek completion methods that will increase reliability, flexibility, and eliminate future interventionsstrategies which further add to well-completion complexity.The Gulf of Mexico is a prime area for deepwater completions, and because of the extensive need for sand control, fracpacked completions have become the norm as they offer reliable sand control and long-term completion efficiency with higher sand-free producing rates and faster reserve recovery. The application of intelligent well designs provides operators with other advantages with respect to cost-effective development of multiple, smaller reservoirs.Operators are continually faced with the need to balance the cost and risks associated with well complexity against the cost and risks of future interventions -both of which are impacted by ever-increasing day-rates and the tight availability of rigs and multi-service vessels needed for intervention.The challenge of combining intelligent, multi-zone completions with sand control is further complicated when dealing with deep, high-pressure deepwater wells. Lessons are being learned every day in these arenas. This paper summarizes two examples of multi-zone, frac-packed, intelligent 15k deepwater completions that were recently undertaken in the Cottonwood project in the Garden Banks Block 244 operated by Petrobras America. Measures taken to streamline and mitigate risk during rig operations and to reduce non-productive time through inspection and qualitycontrol efforts will be discussed. Project Description and OverviewThe Cottonwood Deepwater Project is located in the Gulf of Mexico's Garden Banks Block 244, approximately 138 miles south of Louisiana in 2,118 feet of water. The prospect consists of Pliocene and Upper Miocene turbidite sands that have filled in pockets on the flank of a remnant salt feature. The complex structure and inherent stratigraphy as well as the potential for compartmentalization provided a myriad of challenges for the geoscientists. The many deep and highlypressured reservoirs added further challenges to the success of the well completions.In 2005, Petrobras America acquired a 100-percent working interest (WI) and became the operator of the block. Mariner Energy joined as a 20% WI partner prior to the sidetracking of Well 'B'. The sidetrack confirmed 40 meters (130 feet) of natural gas and condensate pay.In September 2005, Petrobras America announced an ambitious plan to drill an additional well, complete both wells, install production facilities, and begin production by early 2007 -less than 15 months from project sanction. Petrobras achieved this timeline, and the wells are now Petrobras' deepest and highest-pressure producing wells worldwide. Cottonwood was developed as a subsea development with a 20-mile flowline to a production platform in East Cameron block 373. The planning schedu...