Vol. 59 No. 9
September 2007
Dennis Denney, JPT Technology Editor
Composite Cement Retainer
BJ Services’ Python composite cement retainer (Fig. 1) is a substantially nonmetallic tool used for squeeze cementing. The sleeve valve is stinger-controlled from the surface by picking up to close and setting down to open. The composite cement retainer also can be used for downhole well control, primary cementing, flow testing, and as a plug for temporary well abandonment. The materials ensure a longer lifetime in high-temperature wells. The small gauge-ring diameter provides increased running clearance. The design is such that small pieces are generated during removal, and they are easily circulated out, including the slips. The design ensures that all components are rotationally locked, and it uses a pressure-balanced sleeve valve. The retainer can be set mechanically or on wireline.
For additional information, email sales@bjservices.com.
Fig. 1—BJ Services’ Python composite cement retainer.
Metal-To-Metal Seal
Caledyne has introduced its retrievable metal-to-metal (MTM) downhole seal system for mature and challenging oil and gas reservoirs. The seal (Fig. 2) is designed to replace traditional elastomeric or rubber seals on downhole tools such as packers, bridge plugs, and liner hangers. The downhole seal consists of a flexible material contained inside a metal shell. The structure creates a complete metal barrier in the well, which, when fully energized, protects the flexible material from harsh downhole conditions. The system acts in a manner similar to a standard rubber or elastomeric seal, while remaining resistant to high hydrogen sulfide and carbon dioxide concentrations. Performance rated to more than 10,000 psi at 300°C, the seal can be installed on permanent and retrievable packers, bridge plugs, hanger packers, and subsea sealing applications such as plugs and flange seals. The first installation of the seal on a liner hanger was in the North Sea in late 2006. Applications include high-pressure/high-temperature, steamflood, and well-abandonment projects. The seal is available in 5‑, 5 1/2-, 6 5/8-, 7-, and 9 5/8‑in. sizes, and all are suitable for both permanent and retrievable applications.
For additional information, visit www.caledyne.co.uk.
Fig. 2—Caledyne’s elastomer-free high-performance MTM seal.
Compressor Lubrication
Anderol’s Royco889 is a reciprocating-compressor lubricant. In Canadian oil fields, where temperatures can fluctuate more than 50°F in a 24-hour period and most of the crankcase components are steel, aluminum, and cast iron, the drastic change in temperature creates water condensation, causing rust to form in the crankcase and cylinder areas. Water condensation from well-quality gas includes many organic and corrosive components, which can exacerbate the rust problem within the compressor. The specialty lubricant is a polyalkalene-glycol-based fluid. The synthetic-based formulation effectively removes water from the crankcase, significantly minimizing the opportunity for rust to form. Traditional mineral-oil and synthetic-based compressor lubricants are soluble in gas, and gas is soluble in the lubricant. This relationship causes a deleterious effect on the quality of both the lubricant and the gas. The specialty lubricant resists gas absorption into the lubricant and liquid absorption into the gas, extending the application life of the lubricant and enhancing the quality of the sale gas. Reciprocating compressors can use gas from the compressed stream as fuel, and contaminants in the gas can cause deposits on the exhaust valves. In field tests, these problems were eliminated with the improved quality of the com-pressed gas. The extreme-cold-weather properties eliminated the need to warm the lubricant before starting the compressors.
For additional information, email jcohen@anderol.com.
Pipe-In-Pipe Insulation
Corus Tubes and Cabot Aerogel have developed a hybrid-insulation pipe-in-pipe system (Fig. 3) insulated with Nanogel aerogel, a nanotechnology-enabled combination of silica aerogel and polyurethane foam. The system combines the ultralow conductivity and wide temperature-stability range of the silica aerogel with the strong bonding of polyurethane foam. An inner layer of aerogel placed in direct contact with the inner pipe and the outer layer of polyurethane foam create a bond between the aerogel layer and the outer pipe. In addition to providing mechanical support, the polyurethane foam compresses the aerogel layer to improve thermal performance. Operators planning to develop and extend production capacities of high-pressure/high-temperature (HP/HT) and remote fields could apply this solution to flow-assurance issues to increase output and manage costs better. The combination of the aerogel’s ultralow conductivity and wide temperature-stability range is suited to withstand the extreme operating temperatures and transfer axial and radial loads associated with HP/HT flow systems.
For additional information, visit www.corusgroup.com.
Fig. 3—Corus Tubes’ pipe-in-pipe system.
Three-Sampler System
Jiskoot combined three sampling systems for a single installation on a North Sea production platform. The systems provide the operator with daily and weekly sampling data. The setup (Fig. 4) comprises a liquid fast-loop system, an automatic gas-sampling system, and a manual gas-sampling system. The combined system was in-stalled in an open frame to allow installation that takes advantage of the existing fire- and gas-detection systems. The liquid fast-loop system uses three Jiskoot-210 cell samplers. Each liquid sampler has a bypass valve that enables it to be serviced while continuing to use the sampling system. Each gas system has two Jiskoot-G5 gas samplers, and each sampler can be isolated from the line with double block-and-bleed valves. Each sampler can feed one of two Jiskoot CPC-sample receivers, fitted with 80% proximity switches, by use of an electrically operated solenoid valve. The receivers maintain samples at the line pressure to ensure sample integrity.
For additional information, email jmoreau@jiskoot.com.
Fig. 4—Jiskoot’s three-sampler system for the North Sea installation.
