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Technology Applications

HP/HT Liner-Top Packer

With standard service ratings up to 15,000 psi and 400°F, Weatherford’s SwageSet liner-top packer (Fig. 1) meets International Organization for Standardization 14310 standards and is V0 qualified, demonstrating its capability to withstand combined loading conditions while maintaining seal integrity. In high-­pressure/high-temperature (HP/HT) environments, this packer increases reliability with a patent-pending seal ­assembly that is swaged to the host casing. Run as part of a liner-hanger assembly, the packer element forms a permanent, antiextrusion seal between the liner outside wall and host-casing inside wall. The seal is formed by transferring set-down weight through the ­polished-bore receptacle and into the integral swage, firmly sealing the packer element against the host-casing inside wall. Setting force is permanently locked into the element with integral body-lock rings. The packer’s seal system consists of ridge-shaped elastomers bonded to an expandable-metal ring and is less susceptible to swabbing off than conventional, all-­elastomer elements when running in the hole or circulating at high flow rates during well-cleanup or cementing operations. The packer serves as a positive high-performance barrier at the liner top, preventing gas migration and isolating annular pressures.

Downhole Casing Orientation

IWC announced the first downhole operation with its Casing Orientation Tool. The tool was used for orientation assurance at a depth greater than 2500 m for two premilled windows on a ­multilateral-well casing operation in Norway. The tool was run with the 9⅝-in.-casing string (Fig. 2) and then provided real-time orientation data to the surface by use of the company’s wireless wall-mounted telemetry system. Without the need for further well operations, cement was pumped through the tool and it was sacrificially cemented in the well with the casing. Subsequently, the shoe track was drilled out successfully by use of conventional techniques. The telemetry system provided real-time data using mud-pulse telemetry, while retaining through-bore access in the tool, enabling cementing and intervention operations to continue. This telemetry technology, combined with critical data sensors such as orientation, pressure, and temperature, provides data on demand during well-­construction operations while allowing through-bore access for pumping, cementing, or intervention. Critical well-­construction activities, such as orientation of multilateral completions or orientation of tubing-conveyed-­perforating guns, can be performed with high precision and confidence.

Formation-Damage Removal

Peak Well Systems added the SIM ­FloWell (Fig. 3) to its SIM System well-­remediation and flow-control tools. The new tool is a slickline-set remedial technology that is capable of removing formation damage within selected downhole zones to improve productivity. This system improves well productivity by removing certain types of formation damage (e.g., crushed zones in perforation tunnels and tenacious filter cake and scale) in oil and gas wells that were wireline perforated. The condition of the near-wellbore region is critical in producing hydrocarbons, and the perforating process is a major contributor to skin damage. The severe compressive force of perforating can reduce the permeability of the surrounding rock, which in turn reduces productivity. Used in conjunction with the company’s SIM Plug System to provide selective isolation of the zone to be treated, the treating tool induces a sudden pressure drawdown in the wellbore, causing a surge of fluid inflow from the reservoir to reduce the skin damage. Because the tool is run, set, and retrieved on slickline, it offers a low-risk intervention to clean up wellbore damage while conducting routine slickline operations.

Conical-Diamond-Element Technology

Smith Bits, a Schlumberger com­pany, has introduced its Stinger conical-­diamond technology. The polycrystalline-diamond element enables high point loading, to fracture rock more efficiently during drilling to increase the rate of penetration (ROP) and durability. Developed with proprietary ­synthetic-diamond-manufacturing technology, the conical-diamond element has an ultrathick polycrystalline-diamond layer that is significantly thicker than that of conventional polycrystalline-diamond-­compact (PDC) cutters. The element’s shape is optimized for strength in axial compression. When centrally positioned in a PDC-drill-bit cutting structure (Fig. 4), the new element improves performance by crushing the formation core at the borehole center, increasing drilling speed. Using the company’s IDEAS integrated-drillbit-design platform, extensive simulations were conducted showing ROP increases in several rock types, including shale, limestone, and sandstone. The virtual drilling environment demonstrated that central placement of this element would yield an ROP increase of at least 18%. In the Williston basin, an 8¾-in. PDC bit typically is used to drill the vertical hole before the curve and the lateral section in the Bakken oil-bearing sands. In field tests, centrally placed conical-diamond-element technology was added to the baseline vertical-section-drill-bit design. Average ROP was increased by more than 46% compared with the next-best performance in offset wells, with a record ROP increase of 77%.

Reducing Crude-Transmission Viscosity

STWA’s AOT 2.0 (Fig. 5) Midstream product is an add-on system component for pipeline pump stations. It is designed to reduce the frictional-­pressure loss of the pipeline as the crude oil moves between pump stations along the pipeline. By reducing the ­frictional-pressure loss in the pipeline, pump-station operation requires less pressure to overcome the pipeline’s friction per mile, leading to greater energy efficiency and higher maximum flow rates achievable within the pipeline’s pressure limits. This turnkey product uses an ultralow-amperage electric bath to encourage particulate-matter aggregation of the paraffin or asphalt content of the crude oil being transported, to reduce the viscosity of the crude oil quickly and easily. The system has been tested by several entities, including the US Department of Energy, which reported viscosity reduction as great as 56%. Each unit has a maximum flow rate of 5,000 gal/min and is designedfor installation as parallel units to anypipeline flow rate, with a minimum of components and with negligible maintenance required.

Aqueous-Waste Treatment

The aim of Centrifuges Un-Limited’s ELVOS waste-treatment unit (Fig. 6) is to split a primarily aqueous waste containing oil-based-mud solids and oil into clean water (for discharge to sea), clean oil (to be recovered and recycled as a fuel), and solids (for disposal or for further thermal treatment at the source). This separation is achieved by use of a three-stage process. Stage 1 removes the heaviest of the solids from the aqueous waste, clarifying the liquid so that only ultrafine particles remain. Stage 2 removes the finer solids and splits off most of the oil. Stage 3 is the final polishing step for the water, removing any remaining particulates and traces of oil from the effluent. Before discharge, the final effluent is tested to confirm that the hydrocarbon level is less than 30 ppm. The unit can be operated safely by one person and uses minimal consumables. Its small footprint requires less space than a 20-ft container. The system is capable of reducing oil-in-water content to less than 5 ppm, to meet the strictest standards and operate within the world’s most environmentally sensitive locations.

Oilfield-Data Management

Senergy Software has released ­Version 3.8 of its Oilfield Data Manager (ODM) software suite, with significant changes, particularly in the user interface. This version includes Analysis Sticks features and enhancements to the reservoir-­performance-module 3D Viewer. The geological tools enable storing, integrating, interpreting, and presenting many kinds of well-based data. The software enables incorporating and visualizing many forms of data, with the objective of using all available information to make an informed interpretation of the subsurface. The reservoir-­performance-module 3D Viewer makes time-based data viewable in 3D and allows the user to roll time back and forth to examine dynamic behavior. A new method for handling core shifts, which can be associated with discrete and curve data, enables the core shift to be applied automatically wherever these data are displayed such as within charts, maps, and crossplots. A new Heatmaps chart item can be used to display any numeric data, such as discrete sample data or log-curve data. A color gradient is used to represent numerical variation across selected data types for a particular well. A new Dictionary Summary provides a powerful tool for managing dictionaries within the suite.

Replacing Hydrochloric Acid

PZS Stabilization introduced its SGA-1 seminoncorrosive acid to the oil and gas industry. This new acid in the NCA Products line enables more-­environmentally-proactive fracture-treating processes. The seminoncorrosive acid is made specifically to replace hydrochloric acid. Unlike hydrochloric acid, this seminoncorrosive acid has no adverse environmental effects. The basis for this technology is a patented stabilization and production process related to the hydrogen ion tetrahydrate molecule. The proprietary system enables isolation of hydronium, the ion that determines the pH of acids. Even though this solution is seminoncorrosive, it is extremely safe, offering benefits including worker and environmental safety. Whereas other acids, including hydrochloric acid, can cause burning, this seminoncorrosive acid is safe to handle. Skin toxicity tests show that this seminoncorrosive acid has a corrosive nature comparable to that of water, with a level of 0.02 on a scale of 0 to 5. When mixed with water, this semi­noncorrosive acid causes no exothermic reactions or excessive heat reactions. This seminoncorrosive acid is formulated specifically for fracturing treatments and will perform better than hydrochloric acid.

BOP Hydrostatic Testing

Clover Tool offers blowout-preventer (BOP) hydrostatic-test units for BOP, hose, manifold-valve-system, and ­riser-line hydrostatic testing. These all-­electric test units have a small footprint, are explosion proof, and are easy to customize, maintain, and operate. Model CTU-20P-D2-4 (Fig. 7) is a dual unit that offers triple-hydrostatic-test capabilities up to 30,000 psi. During critical operations, one side can be used as an immediate backup. When operating in tandem as a single station, it can reduce BOP-fill/-test time by half. Operating independently, integral twin recorders allow separate tests at different pressures simultaneously. The unit has redundant high-pressure valving, providing washout and leakage protection. An auxiliary fluid-supply connection provides a direct quick-fill port (5,000 psi). Valving and gauges can be set for different operational modes and are switchable without opening safety-interlock doors. Individual operational controls are accessible from either side (the chest-high console is mounted for easy operator view). Filter elements are available in various micron values to accommodate customer requirements. For less-critical operations, a 15,000‑psi single-test unit, Model CTU‑15P-S1, is available.