Additive manufacturing repairs oil and gas industry
Rachel Lawler speaks to Dr Paul Goodwin, R&D Metallurgist at Laser Cladding Technology Ltd, about repair and additive manufacturing solutions for the offshore oil and gas industry.
When we talk about 3D printing, many of us immediately discuss using the technology in our homes. Soon we could be replacing broken parts in our household appliances at the press of a button and the concept opens up a wealth of possibilities for making do and mending. Reducing the cost of making these one-off items is one of the major benefits of this technology, but are we thinking too small?
The oil and gas industry might not be the first sector that comes to mind when discussing additive manufacturing, but the need to reduce the costs of bespoke parts is not limited to small-scale operations. Shrinking profit margins are a concern across the board, and the offshore oil and gas sector, where repair works have long been a priority, is no exception.
Dr Paul Goodwin, R&D Metallurgist at UK company Laser Cladding Technology Ltd, works with companies operating in the North Sea and around the world. He explains, ‘Around 92% of our production work remains oil and gas related, where laser cladding is used to apply abrasive-resistant, hard-facing materials to the surfaces of down-hole tools and drill string sections.’
Goodwin is currently working on 20 different R&D projects, many of which are aiming to develop new solutions for the oil and gas industry. This work will be beneficial in the coming years as the oil and gas industry changes. He explains, ‘Oil fields will increasingly move towards deeper waters in more hostile and challenging environments – including ocean depths of more than 2,500m, more remote locations, sour well conditions and Arctic environments. These environments place increasing demands on materials, with sour well conditions being particularly corrosive’.
How the industry responds to these changes is still under debate because the future economic viability of extracting from these locations is unclear. Goodwin sees part of the solution coming from materials innovation. ‘The most challenging and hostile environments are likely to dictate a change from the use of stainless steel components to an increased use of nickel-based alloys, such as Inconel 625 and Inconel 718, to provide the necessary corrosion performance. Manufacturing components with these materials involves significantly higher costs, as nickel alloys are much more expensive than steel. This opens up opportunities for less conventional manufacturing routes, such as hot isostatic pressing and additive manufacturing to provide more cost-effective solutions and less material waste.’
Some changes have already come into effect, with many manufacturers looking to extend the life of existing kit to supplement investment in new equipment. Goodwin explains, ‘The need to reduce the overall cost of ownership of expensive downhole tooling has encouraged the use of repair and manufacturing of worn components. The laser cladding process, with its ability to rebuild worn areas back to original dimensions, is ideally suited to this. Just five years ago, the use of repaired downhole tools was rejected as too risky in terms of potential failure. Now, around 10% of our production work is the repair and remanufacture of worn tooling. One downhole component has recently been repaired for the third time and is currently on its fourth operational cycle’.
The economic benefit of this approach could be huge. Goodwin explains, ‘When you consider that each of these tools costs tens of thousands of pounds, and they can be repaired and put back into service at a fraction of the cost of a new tool, the economic case is clear and the volume of remanufacture work is expected to continue to increase.’ These savings are enough to persuade the industry to consider using additive manufacturing. He says, ‘The growing acceptance of laser cladding as a method for repair and remanufacture of worn components has increased interest in the concept of producing new components via additive manufacturing technology.’
Goodwin believes the industry is beginning to investigate the cost effectiveness of optimised combinations of additive manufacture and subtractive manufacture, in the same way as the aerospace industry. ‘There comes a point at which it is cheaper to add raised surface detail to a basic component shape than it is to take a much larger billet of expensive alloy and machine away the unrequired material. In the past six months, we have produced the first commercial parts for a customer using a basic machined core tube section with the required raised spiral blades added entirely via laser cladding.’ These configurations would usually be machined out from a much thicker tube.
‘When you consider that laser cladding also offers the ability to add a more expensive material selectively to the surface of a cheaper component body, the potential economic advantages would appear to be significant.’ Goodwin uses the example of cladding a cheaper, slightly undersized steel component body with a nickel alloy such as Inconel 625 to provide the desired surface properties. He explains, ‘This would just need minimal surface machining to produce a component that might otherwise have to be machined from a very large nickel alloy billet.’ Goodwin believes these developments will play a key role in the future of the industry. ‘I see the potential advantages of cost-effective manufacture of new components from increasingly expensive alloys via hot isostatic pressing and additive manufacturing routes. This will ensure their continued development and acceptance in helping to meet the ongoing challenges facing the oil and gas offshore industry in the coming years.’
For more information, email Paul Goodwin, firstname.lastname@example.org
BSc in Materials Technology, followed by PhD in Metallurgy at University of Surrey
Joined UK MoD research organisation in Farnborough, now known as QinetiQ
Moved to Castings Technology International
Joined Tata Steel, R&D
Laser Cladding Technology Ltd