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Several myths have historically permeated the oil industry. These myths typically included: "I can't gain incremental production from a lateral exceeding 1500 ft", "I have to produce my well at the critical coning rate to prevent early water production", and "I have to gravel pack my well to achieve sand control and completion longevity". These myths are being conquered with the generational development and implementation of Inflow Control Technology that allows the wellbore to access and produce larger reserve volumes while eliminating the onset of early water production and/or premature gas breakthrough. Inflow Control Technology enables the prevention of water/gas breakthrough by passively controlling the inflow profile along the length of a well. An increased understanding of wellbore and reservoir fluid dynamics has been achieved through the continued research and application of this technology. To address the diversity of reservoir conditions, this understanding has spawned the integration of state of the art completion and inflow control technology to achieve well specific solutions. Optimum completion solutions should be designed to address the reservoir characteristics. Today, the industry has delivered sand control completions in lateral lengths exceeding 11,000 ft, eliminated water breakthrough in naturally fractured carbonate formations, and provided sand control without gravel packing in formations that would have otherwise required a gravel media. This paper discusses the origin of the historical myths and the case histories leading to the obsolescence of these myths. The global applications reviewed include completion installations in the UK and Norwegian North Sea Sectors, and Saudi Arabia. Advanced Completion Technology The key to increasing the Net Present Value of a reservoir is to increase recoverable reserves while denying sand influx, delaying unwanted water or gas production, reducing well count, and ensuring completion longevity. Horizontal wells can increase reservoir hydrocarbon recovery but also pose unique reservoir drainage challenges. Without proactively managing inflow, destructive erosion of the sandface or early gas or water breakthrough is likely because frictional pressure drop causes the flow to be unevenly distributed and greatest at the heel of the horizontal section. Uneven drawdown dislodges sand grains, which follow the path of least resistance to create localized problems that can disable the well, or at least precipitate a costly intervention. Consequences can be serious and include limited horizontal length and significantly shorter productive well life, both of which leave reserves in the ground. Inflow control devices (Figure 1) were developed to create a uniform production profile along the entire horizontal section of a well and to virtually eliminate annular flow.[1,2,3] This greatly reduces the risk of "hot spotting" which is the primary cause of plugging and erosion in sand control screens. By eliminating the annular flow, sand dislodged from the formation will not be transported and redistributed down the annulus. This reduces the requirement for gravel packing and increases screen life.[4,5] Figures 2 through 5 illustrate the effect that inflow control devices have on the water-oil contact and the gas-oil contact. Figure 2 shows a horizontal well with standard screens and the pre-production state of the water-oil contact and gas-oil contact. With standard screens, the inflow into the well is greatest at the heel and thus the water and gas move quickly toward the heel, Figure 3. This phenomenon results in unrecovered oil, Figure 4. A horizontal well completed with inflow control devices will create a uniform inflow profile into the well, thereby pulling the water and gas evenly toward the well, Figure 5. A completion can now be designed for maximum reservoir recovery by increasing well length and alleviating gas and water coning risks. This can also reduce the number of wells required for efficient hydrocarbon recovery in the reservoir, greatly reducing field development costs. Inflow control technology was developed to address these issues.

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractHorizontal wells on a global basis continue to serve as a primary well type for improving recovery efficiency, increasing reservoir drainage area, delaying water and gas coning, and increasing production rate. However, in longer, highly deviated and horizontal wells, non-uniform flow profiles can result in premature water or gas breakthrough, screen plugging, and erosion which can shorten well life and decrease well profitability. This paper describes historical and new applications of a proven production technology system that optimizes production, delays water and gas coning, minimizes annular flow to prevent erosion, and ensures uniform inflow along the lateral at the cost of a minimized pressure drop in high-rate horizontal wells. Global applications to date of this system include sandstone and carbonate formations as well as light weight and heavy oil. The case histories presented include the Norwegian Sector of the North Sea and carbonate formations of Saudi Arabia, where this production technology, combined with sand control technology, has resulted in significant savings for the operator and improved production in horizontal oil wells.

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TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractWhen operating companies and the service companies combine teamwork and technology development with cohesive communication and planning, the result is proper integration of multi-discipline technologies to ensure successful field applications. The authors will outline some of the obstacles encountered and describe how the tools and procedures were designed to optimize reliability and achieve completions with better well life.Completion case histories are reviewed for wells in Brazil's offshore and deepwater Campos Basin, and deepwater Gulf of Mexico. The discussion addresses well planning, pumping operations, frac-pack design, selection of well screens with extended longevity and fluid systems that prevent formation damage.Openhole deviated and horizontal completions continue to be a primary method for reducing cost and improving recovery by maximizing reservoir contact. Integrating this technology with Intelligent Well Systems achieves a significant reduction in the number of wells required to maximize well productivity and reservoir drainage. Openhole completions have been utilized to successfully develop many of the reserves in offshore Brazil. These completion types include horizontal producers and injectors, gravel packs, stand alone screens, openhole gravel packs with annular isolation and integration of Intelligent Well Systems.Globally, technology has enabled the successful application of gravel packs in lateral lengths exceeding 8,300 feet, and water depths exceeding 6,100 feet. The growth of frac packing in deepwater Gulf of Mexico has intensified engineering efforts to meet the demands specified by the operating companies for fracturing formations with high permeability. Frac-pack applications in deep water can require pump rates exceeding 60 barrels per minute and proppant concentrations of 15 ppa. Specialized tools and performance software have advanced to address the increasing demands and risk management required in today's deepwater market. The evolution of technology is enabling reduced operations risk, better reliability and enhanced oil recovery.