Imagine you’re a customer waiting on a replacement for a broken part for your washing machine, or the operator of an aircraft fleet forced to ground a plane due to a lack of parts when faults occur. Or, even more critically, a doctor in a hospital working with a shortage of equipment, as machines in need of repair lie idle.
Such situations are far too common. Often, they occur because of hold-ups in, or a lack of production within a supply chain.
For example, when an airline changes the layout of the cabin, it needs to plug the gaps between old and new components using spacer panels. Producing these by injection moulding will first require the design and production of a mould, which takes multiple weeks to produce. One false step grounds an aircraft for weeks. In the meantime, manufactures must get both the requirements right and make enough of the parts they need to complete the job. Such delays are inconvenient at best, costly at worst.
Delays versus inventory in manufacturing
Now imagine yourself as the manufacturer. One of the big challenges faced by industrial product manufacturers is to deliver spare parts to their customers – whether other companies or individual customers – on time when needed, as per their contracts. After all, to fail to serve the customer is to lose business.
To fulfil such obligations, manufacturers need to keep large numbers of spare parts, covering all eventualities in their inventory – even if their customers may only need a few every year. This means manufacturers spend time and money producing parts that customers never use. These parts also incur an additional cost when it comes to secure storage.
And then, if available spare parts are no longer fit for use, it leaves manufacturers with a great deal of waste to dispose of. Increasingly, the pressure is on to do this in an environmentally friendly way, incurring yet more cost.
Cutting corners to keep costs low is also not worth the risk to reputation when it comes to customer safety and satisfaction. The parts may not be of appropriate quality.
And then there are elements outside of the control of the supply chain itself – a disruption in transportation links which delays the delivery of parts, items broken or going missing en-route. Finding or manufacturing a replacement can take several more weeks.
It’s clear that traditional manufacturing methods and the impact they have on the operation and sustainability of a supply chain are no longer fit for purpose. As many companies face pressure to tighten their belts as well as operating in a greener fashion new technology, like in many other industries, is bringing new solutions.
Where traditional manufacturing falls short, 3D Printing can pave a new path to build a resilient and sustainable supply chain.
3D printing a more sustainable supply chain
Conventional manufacturing typically removes materials from a larger block to achieve the desired shape and finish. By contrast, 3D Printing, or additive manufacturing (AM), is the process of producing parts layer by layer to a near final shape from a digital design. AM can produce parts with complex shapes – often which cannot be produced by conventional manufacturing – in a wide range of materials, both metal and polymer. AM gives engineers freedom in their designs beyond the limitations of traditional manufacturing processes.
Initially, engineers used AM to swiftly develop prototypes during product development process. The technology has quickly grown in popularity for producing finished parts for products destined for market. Today organisations across industries such as aerospace and defence, automotive, medical and others are using AM for producing tools, jigs and fixtures and, of course, spare parts and for serial production of parts.
3D printing vs traditional methods
There are a number of reasons why 3D printing, or AM, is proving to be more effective than traditional methods for manufacturing spare parts are wasteful. First is the ability for low-cost customisation. Producing a part with a specific shape usually requires something called a die, or tool, made of steel which can be very costly. Also, a machine has to be set-up specifically for this purpose, which requires additional time. Making a single part at a time can come with a large bill – often larger than the value of the eventual part produced. Producing multiple parts the same die or tool reduces the cost of course, but also limits design possibilities.
AM doesn’t require a die. It can produce parts with complex shapes more swiftly. Manufacturers can also produce these parts in low quantities, enabling manufacturers to respond to individual supply demands – keeping customers happy and reducing the need to create excess, typically unused and wasted, stock of parts to cover “just in case” scenarios.
AM can also help to build supply chain resilience. Making parts within 2-3 days helps supply chains to be responsive and avoid supply disruptions by providing an “on demand” service. For example, Daimler Bus has authorised its coach operator customers to produce specific spare parts on-demand using a certified and validated process so that they do not have wait for the parts.
Small scale manufacturing means more orders for small businesses
Such practices also work well at the local level. This brings more business to SMEs and allows those which need the parts to more swiftly serve their customers as the chain becomes shorter. A case in point is small injection moulding manufacturers, whose business models are based on high volume and low cost hence severe competition from low cost manufacturers overseas. But, if organisations can produce these moulds using AM, it will not only reduce cost and lead time, it will also enable injection moulders to produce customised parts in low volume, enhancing their business model. Companies like Nexa3D provides such free-form injection moulding technology.
Moreover, parts produced using AM can have a lower overall carbon footprint than those made using traditional methods. This is due to a number of factors. AM parts use or waste less material thanks to the method of part production and avoiding surplus stock, as well as shorter transport routes due to more localised production.
Airbus found exactly this in using AM parts which weighed 55% less and used 90% less materials. Others can be recycled or produced by recycling other materials such as fishing nets. My own research shows how UK based Filamentive and Fishy Filaments are proudly showcasing the circularity potential of AM.
Limitations of 3D printing
But there are limitations. Only a few parts in a portfolio of a company can be produced by AM. Companies need to identify those parts systematically using both design and supply chain data or expert knowledge and consider redesigning to make parts feasible to be produced by AM.
The companies also need to choose the appropriate AM technology, the equipment and materials. For different AM technologies, parts need to undergo post-processing, require quality assurance and adherence to standards. Other challenges exist in terms of ensuring the security of the design files and product authenticity. Companies like Autentica are trying to address the above problem by using a non-fungible token enabled system of identification to help avoid counterfeiting.
AM has potential to improve resilience and sustainability of supply chains, but it requires a concerted effort by manufacturers to systematically adopt the technology, develop in-house capabilities over time and use the AM service providers to address some of the capabilities they may lack. The investment in doing so will far outweigh the costs over the long-term, but missteps in choosing wrong parts to print or using inappropriate technologies or missing some of the hidden costs in post-processing and quality assurance can prove to be costly and deter companies. It is not to be considered to be a fancy toy which will address multiple problems but instead a friendly set of technologies to develop a well-functioning supply chain – provided the companies do the essential background work to understand it first.
Dr Atanu Chaudhuri is an Associate Professor in Technology & Operations Management at Durham University Business School.
- Digital Supply Chain
- Sustainability