Are Composites A Viable Alternative to Steel in Oil and Gas
The oil and gas industry has traditionally used steel throughout the hydrocarbon value-chain, from the construction of wells and rig systems to onshore pipelines, storage tanks and refineries. However, composites are gaining traction thanks to the numerous advantages they offer over conventional building materials like steel and aluminum. Using composites leads to a reduction in the overall weight of the structure, offers better corrosion resistance properties, reduces the overall operational cost and offers greater design flexibility.
The Current Scenario
Composites are currently used in the oil and gas industry to manufacture risers, drill pipes and tubing, pressure vessels, tanks and pipe systems for fluid transport. They are also used in secondary applications such as in the grids and gratings, handrails, cable trays, ladders, decking and flooring of offshore platforms. Composites are in demand for operations at greater depths as a replacement for metal in subsea piping, such as the growing adoption of thermoplastic composites (TCP) in deep-sea oil and gas applications. In 2009, Airborne Oil and Gas, a manufacturer of TCP, became the first company to develop and deploy an offshore TCP downline. One major factor that aided the adoption of TCP was that it is cheaper and easier to transport, prepare and install than steel.
Composites are being adopted widely across the oil and gas industry. Airborne Oil and Gas’ carbon fiber reinforced PVDF has shown to generate 30% greater savings on as-installed cost compared to steel, while Saudi Aramco has deployed composite materials across significant portions of its oil and natural gas flowline network. In addition, Technip FMC and Magma Global have entered a partnership to develop a new carbon fiber composite hybrid flexible pipe (HFP) for use in offshore applications while Solvay’s partnership with Baker Hughes aims to implement TCP in offshore flexible pipes and risers.
Despite all the benefits that composites offer, the oil and gas industry has shown reluctance in adopting composite solutions. This is often attributed to widespread conservatism among the old guard in the industry, who believe that steel is “good enough” to meet their needs. Another major challenge that composites face is the absence of a global design and qualification standard. Current qualifications for a new composite pipeline product stipulate a minimum required testing time of more than a year and a half. To enable the future widespread adoption of composites, Saudi Aramco signed a charter with TWI Ltd. and the National Structural Integrity Research Center to create the Non-Metallic Innovation Center (NIC) in September 2019. The center will develop field application technologies that are non-metallic and ready to deploy. The aim is to increase the adoption of composites by improving existing qualifications and developing new service standards, inspection and monitoring technologies.
There is an enormous opportunity for the adoption of composites in pipe systems, risers, umbilical and frac plugs, and balls used during hydraulic fracturing. Composites would also be quite useful in repairing offshore defects and are a helpful alternative to traditional maintenance practices because they can often be performed without having to shut down the operations.
Compared to industries such as aerospace, automotive and construction, where composites have been widely used for decades, the adoption rate of composites in the oil and gas sector has been slow. There is a lack of relevant performance information to contend with, particularly in hostile offshore environments, which are a major hinderance to the growth of composites. However, the benefits offered by composite materials outweigh the perceived risks inherent in using new material technologies.