Flexible and light, thermoplastic composite pipe (TCP) is more easily transported and installed in deep-sea applications than conventional metal pipe. Spooled here is 1.2 kilometers of a 6.7-ksi m-pipe, made by Magma Global. Source | Magma Global Ltd.
Not surprisingly, inherently corrosion-resistant composite materials are increasingly used to mold previously metal parts deployed in a host of offshore oil and gas drilling applications. Oceans are Earth’s largest naturally occurring corrosive environment, thanks to salt in seawater. Combine manmade multipliers such as high temperatures and pressures and the host of aggressive chemicals, solvents and other fluids required to operate an offshore oil rig, and you develop a recipe for conditions that, over time, can be corrosive to almost any material — especially metals.
Composite oil and gas parts include non-load-bearing topside platform components, such as fire-water mains, high- and low-pressure tubing, processing vessels and tanks, fire-blast panels, gratings and handrails, as well as newer subsea structures, such as carbon fiber rod umbilicals and
An extensive qualification and pilot program has resulted in AOG’s carbon fiber/ polyvinylidene difluoride (PVDF) gaining acceptance for demanding flowline applications. Source | Airborne Oil & Gas
components for protecting wellheads, manifolds and other equipment related to subsea processing. Composites also are making an inroad into higher volume, more demanding offshore oil and gas applications, such as the systems of pipes producers use to find oil, and bring it up from the wellhead to the surface. As major oil and gas corporations drill more and deeper offshore wells to meet growing global energy demand — research firm Technavio estimates growth of the offshore oil and gas market to grow by $2.79 billion with a CAGR of more than 4% between 2020 and 2024 — pipe demand has also grown, but the development and qualification process for composite pipes has been lengthy.
In the past few years, Airborne Oil & Gas (AOG, rebranded as Strohm in October 2020; Ijmuiden, Netherlands) and Magma Global Ltd. (Portsmouth, U.K.) have been leading the way for development and qualification of thermoplastic composite pipe (TCP) for deep-sea applications, including a number of successful qualifications and pilot programs around the world. In March 2020, AOG/Strohm announced that its TCP made with Evonik (Parsippany, N.J., U.S.) Vestape carbon fiber/PA12 tape was the first to be certified according to DNV GL ST-F119 TCP industry qualification standards after a years-long qualification process. According to Strohm, its TCP risers, jumpers and flowlines are low-cost, corrosion-resistant and deliver a 50% smaller carbon footprint than using steel for the same applications.
In June 2019, Airborne Oil & Gas announced the successful completion of its first thermoplastic composite pipe (TCP) based on carbon fiber-reinforced polyvinylidene difluoride (PVDF) polymer. The company says this pipe provides a solution that doesn’t corrode, is resistant to CO2 and hydrogen sulfide (H2S), and is lightweight and spoolable, with a small bend radius. In 2020, several projects to qualify and build TCP deepwater risers, downlines or flowlines were announced.
Onshore oil & gas
Over the past decade, a composites-aided technology called hydraulic fracturing, often termed “fracking” or “frac’ing,” has enabled the U.S. to increase its onshore oil and natural gas extraction. The process artificially fractures low-permeability rock strata with explosives and then injects pressurized, sand-laced solutions into those fractures to facilitate oil and natural gas extraction. Each wellbore requires 10-40 multi-component tools called “frac plugs” (and accompanying “frac balls”) to stimulate multiple oil- or gas-producing layers, or “stages.” These critical parts are typically made with composites.
In 2014, it was estimated that demand for these downhole parts exceeded more than 20,000 units per week. Reportedly, in 2016, hydraulically fractured horizontal wells accounted for 69% of all oil and natural gas wells drilled in the U.S. — about 670,000 of the 977,000 producing wells were hydraulically fractured and horizontally drilled. According to the U.S. Energy Information Administration (EIA, Washington, D.C., U.S.) in July 2019, the number of active crude oil and gas rigs in the U.S. had reached 1,297. As of July 2020, this number had fallen to 617, up from 456 in April 2020 during the peak of the United States’ COVID-19 pandemic lockdown.
In 2018, Exel Composites’ (Vantaa, Finland) company Diversified Structural Composites (DSC) developed a fiber-optic-embedded carbon fiber composite rod for Ziebel’s (Tananger, Norway) well intervention system. The DSC-manufactured 6.2-kilometer-long, 15-millimeter-diameter carbon fiber rod (the Z-Rod) is designed to deliver multiple fiber optic cables securely into a hostile downhole environment. Typically, the rod is deployed into a producing or injecting well for 48 hours to measure temperature and acoustic vibrations along its length. This enables a variety of applications — including flow allocation, fluid movement visualization, leak detection and stimulation fluid monitoring — which are valuable for optimal well and reservoir management.
In addition to pipes and equipment for natural gas and oil drilling, composites are increasingly used to manufacture pressure vessels to store and transport compressed natural gas (CNG). See “The markets: pressure vessels” for more.
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