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Technology Applications

Hydraulic Rod Pumping

NOV Monoflo has introduced its Corlift high-performance hydraulic rod-pumping system. Pumping sites where conventional pump jacks have not been economical are ideal for these low-profile units, with a small footprint that causes minimal ground disturbance. Additionally, this system requires relatively brief installation time and minimal manpower compared with traditional pump jacks. The system is manufactured in an ISO-9002 certified facility and powered by a 5.7-L EPA-certified field-proven power-skid option. Consisting of a mast mounted directly to the wellhead (Fig. 1), this system has quick and easy stroke-speed and -length adjustments and a pump-fill optimization by use of the hydraulic-pump controller. The system can be used with rod and tubing rotators, and guide wires are not necessary during installation. Available in several models, the system has lifting strength up to 30,000 lbf and stroke length up to 144 in. for various oil- and gas-production applications.

High-Temperature Pressure Measurements

Schlumberger’s PressureXpress-HT service provides accurate formation-pressure measurements under extreme conditions (Fig. 2). Rated at 450°F and  20,000 psi for at least 14 hours, the service acquires pressure and fluid-mobility measurements in a fraction of the time required by multifunction formation-tester tools. Fully combinable with the company’s other logging tools, this tool eliminates a separate wireline run to obtain critical pressure data. Equipped with a flasked high-resolution Quartzdyne gauge, backed up by a Sapphire gauge, the tool does not require thermal stabilization. Coupled with set and retract times as low as 15 seconds, the tool maximizes measurement efficiency while minimizing the possibility of sticking. The tool uses a heat-management-optimized design to perform extended surveys at maximum temperature for measuring formation pressure in a wide mobility range, including very low mobilities. Critical hydrocarbon-fluid profiling can be performed by use of the company’s InSitu Pro real-time quality control and interpretation for pressure and gradient analysis. Pressure profiles and mobility measurements are combined with seismic and log data to develop a static reservoir model after the first logging run.

Topdrive Casing System

Weatherford’s TorkDrive series of tools is a major component of its OverDrive casing-running and -drilling system. The system was designed to provide a safer, more-efficient alternative to conventional casing installation. Mounted to the rig’s topdrive (Fig. 3), the tool combines several conventional casing-running tools into one: power tong, elevator, fill-up/circulation tool, and weight compensator. Hence, the system requires fewer personnel on the rig floor. The company’s new electronic-modular (EM) tool for the system has an electronic controller that can be fully integrated with electronic rig-control systems. Most modern rigs use digital-communication systems and robust industrial networks to interface rig equipment. These systems allow the driller to use a single console to control many rig parameters during operations. The EM tool’s ability to integrate with the rig’s network further reduces personnel requirements. Current casing-running methods with premium connections can require up to four specialized crew members on the rig floor at a time. By use of a fully integrated topdrive-control system, the casing-running crew can be reduced to one person on the rig floor.

Casing-Patch System

Mohawk Energy has introduced its MetalPatch casing-patch system (Fig. 4) developed for cased-hole completions. It is designed for well-integrity issues such as failed completion equipment, leaking connections, corroded casing or tubing, and perforation shutoff, or for relining the entire well. The casing patch can be installed along intervals ranging from 30 to 6,000 ft in length. All sealing elements in the patch, which include the upper and lower seals and premium threads, use metal-to-metal sealing technology. Also, the patch is compatible within the tolerances of the customer’s API casing by use of a proprietary compliant-sealing system that allows reliable sealing throughout the variations in API inner diameters. The system targets operations in which the casing patch can be used to seal off failed fracturing sleeves or to work over old wells with corroded casing.

Resistivity and Imaging While Drilling

Schlumberger’s MicroScope resistivity- and imaging-while-drilling service provides high-resolution laterolog resistivity and electrical images around the borehole in conductive-mud environments. The new 4¾-in. logging-while-drilling tool (Fig. 5), used in 5⅞- to 6½-in. hole sizes, measures azimuthally focused laterolog resistivity and images at multiple depths of investigation. The high-resolution resistivity measurements help to identify bypassed-pay zones and develop better reservoir estimates. It is particularly suitable for formation evaluation in high-angle and horizontal wells. The high-resolution images are provided in real time and in recorded mode, enabling optimal placement of horizontal wells and identification of fractures and faults for completion-design optimization. The service delivered quantitative resistivity measurements and quality borehole images during a 150-well field-test campaign in diverse environments, including carbonate and clastic reservoirs and unconventional shale plays.

Insulated Pipe-In-Pipe Riser

Recent developments in the UK continental shelf have set new precedents for temperature and pressure requirements in rigid-riser systems, with temperatures ranging from +180 down to –30°C. Tata Steel and its supply partners, Eisenbau Krämer and the pipe-bending plant of Salzgitter Mannesmann Grobblech, recently designed and created a system to produce insulated bends for risers and spools (Fig. 6). One of the most significant challenges of such riser systems is how to pass the inner flowline bend into the outer casing pipe while achieving efficient insulation throughout the riser and bend structure. The solution uses a 16-in.-diameter pipe within a 22-in.-diameter pipe to overcome these challenges by deploying granular Nanogel insulation in the annulus of the pipe-in-pipe system. This granular material has trapped nanopores of air, inhibiting heat transfer by conduction, convection, and radiation, and produces a solid yet flexible barrier to retain insulation, allowing movement of the inner and outer bends. Also key to the solution was annular-gap consistency throughout the assembly, which demands tight control of dimensional tolerances during manufacture of the pipe and bends.

Pipeline Cleaning

T.D. Williamson S.A. was contracted to clean two pipelines in southwestern Romania. The lines were choked with produced sand and paraffin. Also, the lines were bent at acute angles at several points and had various internal diameters. One of the lines required installation of a liner into the existing steel pipe, which had to be free of debris. Before cleaning commenced, the operator removed sections with acute bends and replaced them with straighter sections. Pig launchers were installed at strategic points along the line. The pigs were fitted with transmitter units that allowed tracking progress of the pigs by use of the company’s remotely-operated SmartTrack tracking and pressure-monitoring system. To clean the lines, a four-step cleaning program was carried out with special cleaning pigs: a medium-foam pig, an OptionAll 2CC pig, an OptionAll 2CC pig with brush, and an OptionAll pig with gauge plate. Every step involved multiple runs with each type of pig. With each successive run, the pressure of the line dropped and flow increased. Approximately 12 m3 of sand and paraffin was removed, allowing crude to flow
much faster.