There is a famous scene at the beginning of the 1970’s film classic The Graduate when a family friend of the eponymous lead character takes him aside and says, “I just want to say one word to you. Just one word…Plastics. There’s a great future in plastics.”
There is no doubt that there was and is a great future in plastics — or maybe more appropriately, non-metallic materials. There are those in the chemical process industries who do not want their products called plastics. How about polymers? Or maybe one of the many composite formulations, such as fibre and glass reinforced plastics? Take your pick, but any of them will provide a variety of industrial solutions.
Probably one of the biggest successes for non-metallics has been in the automotive industry. The removal of large amounts of metallic elements — much of them the dazzling chrome trim —made modern cars significantly lighter than their predecessors, resulting in greater fuel efficiency even before engineers began to tinker with the engine.
In the subsea arena, weight reduction can, in fact, be addressed in two ways — make the elements lighter, or support the weight using buoyancy. Two of the traditional applications for buoyancy offshore were drilling risers and remotely operated vehicles (ROVs).
Then along came Total’s Girassol project, off Angola, at the beginning of the century. The decision to employ a freestanding riser system, the first of its type in that configuration, required a package that provided both insulation and weight support, and sent the development team off to find a supplier that could provide such a product. This precipitated a fierce competition between several companies, which was eventually won by Balmoral Offshore Engineering, and created a whole new market as this concept began to be used more widely.
Record set
With weight reduction firmly in mind, a very recent development has the subsea industry abuzz. As long as six years ago, Louisianabased ExPert E&P Solutions, a company where the main activity was the repair and maintenance of drilling risers, perceived a need in the completions market for a buoyant landing string.
This is seen as gamechanging technology. By reducing the weight of the landing string, casing string installation could be accelerated with the resulting reduction in rig time and cost savings. One operator told ExPert E&P Solutions that it saw the potential to save $40 million per well, and that by using this new system in a campaign, it could “drill three wells and get the fourth one for free”. It also would allow older rigs to handle very heavy casing strings.
While ExPert E&P Solutions was designing the landing string — working through spinoff company Landing Strings Solutions — it went to Trelleborg Offshore to come up with what would be a technically challenging buoyancy package. The buoyancy not only had to withstand the maximum pressures of very deep water, but also had to cope with high temperatures and exposure to drilling fluids. Additionally, it had to contain no metallic elements to protect the wellhead from any accidental damage.
Trelleborg, which 10 years ago acquired CRP Group, one of the competitors in the Girassol supply competition, developed the chemical formulation for the syntactic foam with a composite spheres buoyancy package (like most of such products, the exact chemical make-up is not made public) as well as a polymer-based clamp and fastener system.
This system had its initial use for Anadarko installing what is said to be the heaviest landing string ever, at just over 1 million tonnes, off Diamond Offshore’s sixth-generation drillship Ocean BlackHawk in 5900 feet (1800 metres) of water in the Gulf of Mexico.
There are actually so many companies supplying thermal and pipeline insulation — quite often, the same firms that provide buoyancy also do insulation — that it would be difficult to catalogue them all. One that has done well in the component marketplace is UK-based Advanced Insulation, which supplied spray-applied insulation and encapsulations to a number of major operators, such as BP, Total, Eni and Chevron, for a range of equipment, including subsea trees and valves.
Another is US-based Materia, which recently picked up the pipeline insulation contract for Shell’s Appomattox project in the Gulf of Mexico. It uses a thermosetting cross-linked polymer, marketed under the name Proxima, which is said to be incompressible at waters beyond 3000 metres (10,000 feet), thus maintaining its structural integrity. Materia will execute this job with pipe coating specialist Bayou.
There are few companies in this field with the pedigree of Covestro, the material science division of chemical giant Bayer that was spun off in 2015. Materials for the offshore sector fall into the company’s Coating, Adhesives & Specialties business unit.
Covestro/Bayer had been involved in elastomers, or more specifically polyurethane polymers, for more than two decades, and the evolution of its involvement in the offshore sector was based on the material properties — corrosion resistance and a measure of flexibility. Products include both pipeline and cable protection as well as pipeline insulation, plus bend stiffeners and restrictors.
The challenges that these materials need to deal with are at the opposite end of the spectrum — low temperatures encountered on the sea bottom and the high temperature of produced fluids.
New players
There are some less familiar names trying to raise their profiles in the offshore sector. Nylacast, which dubs itself as a provider of “engineering plastic solutions”, is looking for applications to replace metallic components with nonmetallics. These include pipeline centralisers, bundle spacers, J-tube seals and protection for flexibles.
Nylacast also aims to enhance the performance of components through custom formulated materials. For example, its centralisers and spacers are made from CF110, an oil-filled cast polyamide 6. This standard polymer has been adapted to meet the specific application, which requires a ferrous coating on the underside and is “creep” resistant.
Also on the lookout for new opportunities is Rochling, a 190-year old privately held German company that only entered the plastics sector in 2000. Half of its €1.5 billion ($1.7 billion) turnover comes from the automotive industry. The company is looking to diversify into other markets, with oil and gas a key target, again to try to take advantage of the lightweight and corrosion resistant properties of plastics as well as the ability to reformulate existing materials.
Rochling is also producing pipeline centralisers, but as well it makes PTFE back-up rings for sealing solutions, valve seats, sheave segments for pipelay spreads, and subsea end-caps. In all of its products, it is trying to take advantage of a good coefficient of friction, thermal stability and mechanical properties of plastic formulations.
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