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Perforated base pipe is an important component in a completion system. Field applications

The use of Underground Gas Storage (UGS) is expected to increase considerably in the near future due to various factors. Many of the UGS wells require sand control. Expandable Sand Screens (ESS) have many advantages as a completion option in UGS wells. But there has always been a concern on the effects on ESS due to cyclic loading. The paper deals with the changes in the borehole that would be caused during annual injection and production cycles from the storage reservoir.

When simulating bolts, the amount of detail to include is often raised. The analyst is left with using judgment in deciding to include or not include details, such as threads. For system models, where the primary bolt function is to transfer load from the cover to the base, thread details are sometimes perceived as not needed. It is believed that a reasonable result can be achieved without this detail. Should the bolt head contact interface be bonded or full, and how does this affect the shank stress, is another concern. This again is a judgment left to the analyst.

Santos Basin is one of the most promising basins of Brazil, recently it was discovered light crude oil of 30º API (American Petroleum Institute), this reservoir of high productivity is located below a salt layer of two thousand meters of thickness. Salt also known as an evaporite rock is found in many hydrocarbon basins around the world. Evaporites are sediments formed initially from minerals dissolved in water, the most common are: halite, gypsum, and anhydrite. These minerals are found in areas that passed by a geological time of high evaporation or precipitation.

For the past few decades, with depletion of hydrocarbons in more readily accessible regions, petroleum operators have shown increasing interests in exploring onshore oil and gas reserves in Arctic areas, which are typically overlain by substantial permafrost layers on the order of 150 to 500 m thick. A key challenge to the completion of these wells is how to manage the impact of thaw subsidence of permafrost layers throughout expected well life.

Thermal technologies are widely used for the heavy oil recovery. The thermal processes usually consist of some variation of Cyclic Steam Stimulation (CSS), steam flood or Steam Assisted Gravity Drainage (SAGD). These thermal recovery applications have experienced numerous well casing failures around the world, often resulting in loss of wellbore integrity, lost production and added costs.

The Extended Finite Element Method (XFEM) capabilities of Abaqus V6.9-EF1 could have a significant impact on finite element modeling of failure for the U. S. Army. The Army has many areas where fracture is important from failure of components, to penetration, to warhead development. To assess the value of XFEM under static loading, comparisons were made with experimental data of notched panels. The panels had different angles of notches. The crack growth direction and applied forces for crack growth were compared to experiments using ABAQUS.

In developing weapon systems for the warfighter, the US Army uses modeling and simulation tools to support the design, test and manufacturing of these systems. One of these tools is Abaqus/Explicit, including the coupled Eulerian-Lagrangian capability CEL. The addition of CEL in version 6.7EF-1 opened the door to a new realm of problems that could not be previously be modeled. With the addition of this new capability came the need for internal validation to establish a level of confidence for the class of problems of interest to the U.S. Army.

Monte Carlo reliability calculations for high-reliability systems are very computationally expensive. Variance reduction techniques optimize this process greatly and directional simulation is one such technique. Directional simulation is particularly valuable for high reliability systems where the failure surface is highly curved or dislocated.