Making a material difference

Two overarching developments are having a significant impact on the machine building sector - advances in materials technology and changes in the way supply chains operate.
Matthew Aldridge, MD of igus UK, explains

Extensive investment in the development of polymer technology over the last quarter of a century means that many products once manufactured in metal are now made from plastic. My own company sees this trend happening, in particular, in the field of bearing technology where plastic is increasingly commonplace.

There are several reasons for this development. For example, plastic bearings (which can be mass produced) reduce cost. They also allow you to use a soft metal such as aluminium as the shaft material instead of the more expensive highly-polished, finely-finished hardened steel required for use with metal bearings.

In addition, plastic bearings require no lubrication, and are intrinsically light in weight and corrosion-resistant. Many sectors – including automotive and aerospace – are turning towards lightweight materials because they reduce emissions, and are easier and less expensive to handle.

Plastic technology is developing fast. For example, the bearing pressure to which you can subject a plastic part has risen dramatically in the last three years. We have raised the maximum recommended surface pressure allowable on a bearing from 150 to 200MPa – an impressive 33% increase. This is allowing its use in an increasing number of applications.

On top of all this, a designer can integrate the bearing and housing as a single component made from engineering plastic rather than have to contend with a number of components in the assembly. This, in turn, accelerates the manufacturing process.

One particularly interesting development is the use of engineering plastics in the 3D printing industry. This is where my own company, igus, scores because we were the first company in the world to launch a 3D printable engineering plastic.

The designer therefore has all the technical benefits we have just been discussing in an engineering plastic filament which can be run through any 3D printer that can print standard ABS plastic.

So, when the customer is trying out a prototype, he or she can 3D print the idea and then wear test it in real life with the material that will be used in the finished product. So the designer is no longer simply testing products for how they fit. Now, he or she can test the fit and the function using 3D materials.

igus was also the first company to develop and supply an engineering plastic in powder form for selective laser sintering, an additive manufacturing process that builds three dimensional parts using a laser to selectively melt each layer of the design in a bed of fine plastic powder. Again, previously, the designer was limited to using basic plastics such as ABS in prototypes which couldn’t be used in a realworld application.

But the materials technology itself is not the only area in which we see big changes. We are also finding that companies at the forefront of materials technology increasingly offer both the materials and the service.

So, for example, as a designer you can now either buy the material from the supplier, or you can send your CAD file to the company and it will 3D print the part for you. In other words, the materials supplier can effectively become a de facto low volume manufacturer of customised components.

This radically reduces tooling costs, and you can test out a number of different iterations of an idea easily, allowing you to move through the steps of the design phase more quickly and at lower cost.

Designers rightly want the best technology, and they want it configured as easily and quickly as possible. As a result, to survive in today’s engineering design environment, progressive suppliers provide online tools to allow design engineers to very quickly arrive at the solution that suits their needs. This means, for example, that a designer can input his or her requirements and then customise the solution quickly online.

So technological change – both in materials and in the way that designers are able to apply them - is a big development in the world of plastic materials engineering.

Unshackle your supply chain
But I believe there is also a second major trend that involves a fundamental shift in the way we do business. It is, I think, generally accepted that UK manufacturing needs to become more competitive in a global market and we therefore need to improve the productivity of the supply chain.

There are many ways to achieve this, but one of the key questions I believe manufacturing companies need to be asking themselves is: are we concentrating our efforts on the areas of the business where we truly add value?

In other words, if you are making a packaging machine then make the packaging machine. Don’t spend valuable time and precious manufacturing resources making, for example, energy chains because an energy chain manufacturer has the resources, facilities and technology to do that far more efficiently than you can.

When I bring customers to our factory and show them what we do, I often witness a lightbulb moment as they realise the sense of this argument.

Just think about it. igus makes energy chains; they come out of the injection moulding machine in component form and we assemble them into a chain. Then we ship them to the customer. The first thing that the customer does is open the box and take the chain apart again to put in cables and hoses before reassembling it. That’s not lean.

Surely, it’s far more efficient to put the cables and hoses in at the point where assembly first takes place and then deliver it to the customer in a format that can be plugged straight into his or her machine. It also means the shopfloor employees can concentrate on the core business, which is what they are good at. The savings that are
possible with this approach without increasing costs are staggering – typically £25,000 to £50,000.

As top management guru Tom Peters put it in his seminal book, In Search of Excellence: “Stick to the knitting – stay with the business that you know.”