The operation of downhole sand-face tools has relied upon depth measurements, downhole indicators that use applied tension or compression noted on the surface weight indicator, as well as hydraulic pressure in order to verify service-tool positions in relation to the sand-face assembly. This strategy has worked well in the past. However, with field developments with increasing well depths, higher-angled wells with increasingly complex geometry, and increasing intricacy in sand-face tool systems, the need for additional methods to aid tool operators in locating and communicating service-tool positions has become apparent. Also, modeling the effects of the pumped treatment on the tool system and work string in real time will assist in understanding when, and if, the tool system will move out of position.The introduction of multiple-zone one-trip sand-face completion systems developed for applications in the ultradeepwater Lower Tertiary play of the Gulf of Mexico has led to the development of a visualization tool that provides the tool operator with additional information to validate conventional tool-locating methods as well as providing a communication interface to communicate the tool information to others. This innovative visualization tool is a software program known as the "Real Time Visualization Service (RTVS)". The RTVS package provides detailed visualization of the entire sand-face assembly, including the service string, providing the tool operator and observers with another tool-location validation method along with an exceptional pre-job planning tool. The visualization software provides the capability to monitor operations at the rig site or remotely from a real-time monitoring site or home personal computer. OTC 23626anchoring the sand-face assembly. The service string is then released, and the tool positions are determined for squeeze, circulating, and reverse positions for each interval to be treated. Completion Planning ProcessThe completion planning for the RTVS service is a stepped process, similar to what is being done today, with the exception of more detail in each planning step. The planning process has three phases: Pre-Job Planning, Real Time Monitoring, and Post Job Analysis.Pre-Job Planning -Pre-job planning is a multi-faceted process. For the purpose of this paper the focus will be on the procedure generation, specifying the completion components, assembly and inspection of the equipment prior to shipping to the well site. Once the well completion is defined, a step-by-step completion procedure is created. A detailed completion schematic will normally accompany the completion procedure and is provided by the service provider. The completion schematic will list the specific completion equipment for the procedure and provides the proposed component depth, length, outside diameter, and inside diameter. During the assembly process, equipment dimensions are verified, equipment is drifted before and after makeup into completion assemblies, and completion assemblies are pressure tested. A sand-...

This paper describes the development and testing of an innovative downhole zonal pressure maintenance device (PMD) developed for open and cased hole well completions. This PMD will be deployed as an integral tubular component in a generation IV single-trip multizone sand control system (STMZ) currently run in deep water and in other unconsolidated soft-rock applications. It will significantly increase the system's capability and provide proven time-saving benefits of such technology into the soft-rock formation arena. Typical generation IV systems currently used isolate the discrete zones from one another and the wellbore. The operational steps include setting the top-most packer first. This process isolates the zones from the hydrostatic overbalance pressure, creating an opportunity for uncontrolled crossflow among zones with differing bottomhole pressures. This crossflow can, and will, move hydrocarbons as well as formation sand into the wellbore therefore certain limitations are placed on the existing STMZ system. The PMD maintains the initial hydrostatic pressures on each zone independently to help prevent uncontrolled crossflow and its detrimental effects. The PMD construction is totally mechanical and fully autonomous, not requiring any signals from the surface for its operation. It has built-in intelligence to sense the array of initial hydrostatic pressures in various zones and to store them for subsequent use. Prototype tools were developed and tested in the laboratory, simulating near realistic multizone completion operations. The PMD design enables the amount of fluid leakoff into the formation to be minimized, thereby reducing formation damage. This capability is accomplished by automatically adjusting the PMDs to the respective zones to reflect the individual differences in reservoir pressure; it is particularly useful for completing wells wherein significant differential pressure exists between compartments because of the depletion that has occurred in some reservoirs. The paper illustrates expected results on a multizone completion and displays the pressure maintenance behavior resulting from the use of this device. Tests were conducted in the laboratory to validate the tool performance under extreme conditions of high leakoff rate in conjunction with an abrasive fluid with plugging tendency (oil-based mud). Another condition simulated relatively high pressure differential (2,000 psi) while reversing out after a "frac pack" operation. The tool design incorporates state-of-the-art technologies, such as 3D printing and hydraulic miniaturization using implementation techniques unique to oilfield applications. Generation IV single-trip multizone system technology has been a key enabler for formations, such as those found in the Lower Tertiary of the Gulf of Mexico. The PMD provides a novel tool to extend these multizone applications to unconsolidated formations and to multizone reservoirs with high reservoir pressure differentials.

Although multiple-zone, downhole sand-control tool systems have been in use since the early 1990s, these systems had been designed for jobs requiring low-pump-rates with low-pressure differentials. Multiple-zone systems capable of high fracturing pump rates and the associated differentials only recently have been introduced to the oilfield. Although these jobs are becoming more common, most of the completions have been limited to four or five discretely treated zones. This paper presents a case history from Indonesia in which a high pump rate, high differential pressure-rated single-trip multiple zone-sand control tool system was capable of treating six discrete zones in an offshore deployment. The challenges for this completion were numerous. Manufacturing lead time was very short, and the system would have to be adapted to the unique requirements of the completion design and the use of new components. Since the proppant and pump rating limit testing for these systems had been based on five zones, complicated calculations and extrapolations had to be used to ensure that the crossover tool would survive the erosive effects of treating six zones. To provide assurance of the service tool's elastomeric seal integrity, a testing program was executed between treatments to provide tracking and verification of conditions. Procedures and equipment would be in place to replace the service tools, if any leaks were evident. Since system installation experience was limited in this area, gathering sufficient knowledge and experience for system deployment had to be addressed quickly. This would require sharing of lessons learned, use of experienced personnel from previous installations, and conducting of detailed training discussions between subject matter experts and service personnel. Deployment challenges and solutions, successes experienced at the well site, and the actual performance of the operations will be detailed in the paper.

This paper demonstrates the importance of wellbore cleanliness during lower, intermediate, and upper completion installations that lead to both successful installation and operation of an isolation barrier valve. This should result in bringing the well into production or injection in a timely and efficient manner. Excessive debris remaining in the wellbore can complicate and delay production or injection and also compromise well productivity by causing damage and preventing installed equipment from operating properly. Post-production/injection debris in the well can also impact and affect production and injection rates. Downhole tools in deepwater environments not operating remotely as designed because of debris can result in a complex and costly intervention. Typically, when this occurs, a drift or bailer run is conducted to establish holdup depth. In some cases, these have tagged up to 50, 80, and 100 ft (in extreme cases, 150 ft) above the valve expected to operate. Sometimes, slickline, electric line (e-line) bailers, coiled tubing (CT), or a work string with a Venturi junk basket are used, and then the valve is either functioned open or the debris is milled out and the valves remotely functioned cycled open once all the debris is removed. Additionally, cases have occurred where the debris is cleaned out, enabling the tool to function and open, depending on tool design. The tools can be designed and qualified to industry standards and tested at downhole conditions, pressure, and temperature with applied tubing and simulated hydrostatic pressure; however, this does not mean functionality cannot be impaired. The importance of wellbore and surface equipment cleanup should not be undervalued. Wellbore cleanout, circulation, displacement, and correct conditioning of fluid are important during the final stages of the operation. If executed properly, these can result in the well entering production or injection on time and without issue. The criticality of robust procedures cannot be overlooked. Not only is it important to condition and displace drilling fluid with clean completion fluid, it is also important to ensure that all debris is removed, including jetting the blowout preventer (BOP) and wellhead cavities before running the completion. Additionally, particular attention should be given to the landing string, tubulars, and drillstrings used to land and lock the completion. All surface lines and pump cavities should also be cleaned before pressure testing. Due diligence during initial cleanout can enable successfully bringing the well on-stream and help prevent costly interventions.

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