Additive manufacturing (AM) parts gain world-first oil and gas certification
September 27, 2017
Tim Skelton reports on the 3D printed innovation that has allowed the Safer Plug Company to miniaturise its pipe tools, with the help of Lloyd’s Register
Additive manufacturing (AM), or 3D printing as it is more widely known, is by no means a new concept, even if the oil and gas sector has to date been comparatively slow to adopt the technology. But that process could be about to accelerate, with September seeing the establishment of a new certification process and the first metallic AM part certified specifically for use in the industry.
With the obvious benefits it offers, it is no surprise that 3D printing is becoming an increasingly prominent feature in many people’s lives. Some have even hailed it as a ‘new industrial revolution’. Unlike conventional manufacturing, objects are built from scratch, layer by layer, rather than by forming them or machining them from a larger block. Ground plastic – or in the most recent example, metal – powder is ‘welded’ first to a template and then to itself by laser in order to form the required product. This allows components designed using computer CAD packages to be built to very precise specifications, within a much shorter timeframe, and with far less waste of materials than standard techniques, all of which helps to slash costs.
In some cases, the technology can reduce the time taken to bring products to market from several years to a matter of months or even weeks.
Despite all the flexibility it offers, the oil and gas industry has until now been reluctant to jump on the bandwagon. The latest certification framework, “Guidance Notes for Additive Manufacturing of Metallic Parts”, developed by London-headquartered engineering, technical and business services company Lloyd’s Register (LR) and produced in collaboration with The Welding Institute (TWI), could encourage a change in attitude.
Why certify? When LR analysed AM technology it recognised a massive potential for rapid growth within the oil and gas industry. Inspired by this, it set out to produce a set of guidelines to safeguard and guarantee the technology, and to give companies the assurance they need that metallic AM parts can be used safely.
According to the group, there are several reasons why such a certification scheme is essential. First, it points out that for offshore products, existing standards cannot be safely applied to the AM process. Metallic AM is similar to welding on a micro-scale, but the control systems and lessons learned from welding are not directly transferable. Moreover, the use of a powder feedstock, new controllable processing parameters and pre-heated parts all result in the need for new design and manufacturing requirements and recommendations. The precision of AM technology is also likely to see existing simpler, but worn-out, components being replaced with far more structurally complex designs with potentially inaccessible internal features.
A second incentive for having dedicated guidelines is that while tests have proved AM parts to be similar in strength to conventional parts, their ductility and fatigue performance can suffer. This is a particularly critical issue in the oil and gas sector, as the parts are often needed for safety-critical applications and are used in harsh conditions, where there is a risk they may fail to meet minimum requirements.
A guided, certified approach to design and manufacture gives end-users confidence in the safety of the components without the need for a ‘belt and braces’ approach with an unnecessarily conservative design. Guidelines also ensure part quality and repeatability.
LR sees its certification system as a “stabilising force” in an emerging and fast-developing new industry. With innovative AM technologies and new businesses appearing all the time, there is pressure on suppliers to cut costs in order to gain a competitive edge. Moreover, the scale of products required for the oil and gas sector means that large-format printers are needed, and these machines may not yet be ready to make key structural components. Certification again brings reassuring guarantees about quality and safety.
The first part The first new component for the oil and gas sector to reap the benefits of LR’s guidelines and receive certification was unveiled in early September. The part is a titanium gateway manifold, designed by British-based Safer Plug Co. (SPC), and built using powder bed fusion by AM production specialists, 3T RPD. It is designed to be included in an assembly for a suite of pipeline isolation tools, which also features the world’s smallest tool suitable for deployment in a six-inch (152-mm) diameter pipe.
According to the designers, the manifold’s complex internal channels meant it could not have been manufactured using traditional techniques. Knowing that it would need independent assurance of the innovative new part’s manufacture, design and production, SPC therefore contacted LR in 2016. Using its framework guidelines, LR was able to monitor and oversee the entire process, assessing not only the materials, but also the manufacturing process and the manufacturing plant itself.
“In taking on this initiative, LR’s Additive Manufacturing group has truly opened a gateway to the future,” SPC technical director Ciaran Early told the press when the part was unveiled. “LR’s pivotal role is to guide suppliers through the codes, standards, controls and best practices to manufacture AM parts, in order that end-users will have full confidence that [a] part meets the required level of criticality.”
What next? SPC says it wants to set an industry example by demonstrating how oil and gas can reap the benefits of AM. Lloyd’s Register will certify the next batch of 10 manifolds, and is working with SPC to develop a Type Approval certificate. This would allow it and 3T RPD to produce both the manifolds and the pipeline isolation tools on demand. LR says its step-by-step certification process will provide both the oil and gas industry and its customers with confidence in the safety, repeatability and quality of complex metallic AM components and equipment. This in turn should boost the adoption of the technology by the sector, and lead to the certification of many more quality-engineered components in future.
“As with all things new in O&G, the operators want to be ‘first to be second’ when it comes to novel technologies,” LR global product launch manager Andrew Imrie told InnovOil via email. “Although many organisations are not openly advertising the fact they are working with AM, we know a number of high profile O&G organisations are at advanced stages of assessing and developing AM for a variety of uses. LR’s role in this is consistent with our approach now for more than 250 years, which is to provide an independent method of assurance for novel technologies in the industrial manufacturing area.”
At a time of low prices, the cost savings and gains in efficiency that this could offer will go some way to helping beleaguered oil companies regain some of their commercial advantage.