Production gets smart

Posted on 9 Sep 2010 by The Manufacturer

Talk of advanced manufacturing across all industry sectors has exploded in the last 12 months. But what does advanced manufacturing really mean for UK companies in terms of processes, skills and competition? Jane Gray finds out.

There is a question mark beside the new Government’s business policies, where after a positive Budget manufacturing is unsure about the future of initiatives like the Manufacturing Strategy and the Manufacturing Advisory Service. This was exemplified by the disquiet following the withdrawal of the pledged £80m loan for Sheffield Forgemasters. Despite this, advanced manufacturing is still the strategic buzz word for the future of British industry.

But this is an ambiguous term for many. The wealth of new high-tech processes that make up advanced manufacturing seem to be poorly understood by the manufacturing community as a whole, in terms of the potential these processes have for bringing competitive advantage.

TM talks to representatives from industry and academia about their involvement with some of the most forward-thinking production methods in development.

Additive manufacturing
3TRPD is a specialist in additive layer manufacturing using precision laser technology. Working with plastics and metals the company boasts the UK’s largest selective laser sintering (SLS) facility and is a leading provider of direct metal laser sintering services (DMLS) to the medical device and aerospace industries across Europe.

Chief executive Ian Halliday explains what this radical new production method could mean for British industry, and highlights the challenges that bar the way for wider adoption: “The potential that additive manufacturing could bring to British industry is massive. But the biggest thing standing in the way of that potential is lack of education and awareness.

“3T holds seminars with existing and potential customers to try and counter this as well as partnering with universities like Loughborough, Oxford and Exeter. We are particularly proud that we have good working partnerships with competitors to help strengthen our emerging industry.” Despite a perception that additive manufacturing is a nascent technique available only to the cashrich for the production of low volume parts, Halliday draws attention to his plastics business. “Plastics now provide us with a profitable and varied market.

Around 30 per cent of the plastics we produce are architectural models and the bulk of our production is on a variety of prototypes for different industries. We also make production parts like electrical windings and there are some exciting possibilities opening up in luxury consumer goods like lamps and jewellery.” What is the benefit of producing these products through additive layer manufacturing rather than injection moulding techniques? “The windings we produce have thin fins about a millimetre apart,” says Halliday. “Creating an injection mould for that shape would be very difficult and the chance of those fins surviving more than a few injections is minimal.

By using additive manufacturing our customer got a significant performance increase, and we’ve produced around 15,000 windings for them.” But it is the metals application of SLS and DMLS which holds the real key to changing industry.

“The potential here is a thousand times greater than in plastics,” says Halliday. “The important thing with metals is for people to understand the limitations of the process. Then they can start thinking about the applications.

“The major limitation in DMLS is in the need to build supports for any surface with an angle of less than 30 degrees to the horizontal. These supports can be machined away but need to be considered in the design phase of a part.” This is not the case with plastics which are light enough to be free forming. Other constraints are material suitability and component size.

Learning to work creatively within these boundaries could change engineering and production practices on a large scale. 3TRPD is about to sign contracts with a large medical company for the batch production of medical implants and it supplies parts to all but one of the big aeroengine manufacturers in Europe. “We are talking about serious parts, like parts for live test-bed jet engines. The products we will produce for these markets are far lighter than anything that could be created using conventional methods [such as milling] because we can build internal and external structures, hollow structures in one go and variegated skin thicknesses. This has the dual advantage of allowing us to optimise a part for specific stress and load expectations. We can create structures that are simply impossible using machining or injection moulding.” However, Halliday stresses that he does not want additive manufacturing to be seen as a panacea or a replacement for more traditional manufacturing techniques. Instead, he explains how additive manufacturing can enhance them.

With injection moulding, for example, Halliday says that it is frustrating that many companies are unwilling to think about the opportunities available through collaboration. “Resistance to change and a persistence in seeing additive manufacturing as a threat is a real barrier and it is stopping the UK tooling industry seizing the competitive advantage they sorely need to rival China and Asia.

“One way that additive manufacturing could give this advantage is through creating more efficient cooling channels in tooling parts. We can easily build conforming cooling channels within a mould – for tooling companies this means that products will cool more evenly and more quickly, reducing faults and maximising throughput. Some companies we have worked with have reported a 25 per cent increase in throughput from this development and sometimes it is more than 50 per cent.”

This form of semi-solid metal casting is commonly used in Asia for the high volume production of small components for consumer electronics.

But improvements in the quality, precision and reliability of the technology means that it could now be exploited in the UK for producing high value components in the automotive and aerospace industries as well as by companies making low to medium volumes of goods for niche markets.

Advanced engineering company Shearline has chosen to pursue this opportunity and, in partnership with the University of Sheffield and the Advanced Manufacturing Research Centre in Rotherham, will soon establish the UK’s first test rig for magnesium thixomoulding.

Charles Maltby, technical and commercial director at Shearline, explained why he feels this is important for British industry: “There are no machines capable of performing this process in the UK at the moment and only about six in Europe. We are behind.

“Magnesium thixomoulding allows designers to experiment with exotic, free-flowing shapes and to exploit the light weight yet resilient qualities of magnesium as a material. High performance motor car manufacturers are already using magnesium to make hidden parts and increase performance.” Shearline has not been shy to grasp the potential of additive manufacturing in creating adventurous designs for their moulds in short turnaround times.

Mr Maltby says that a coalition between these two technologies could open new possibilities to the many UK companies who make low to medium volume products. Using additive manufacturing to grow the tools and then injection moulding a complex design in one step could greatly simplify the supply chain for niche parts and would be cost effective without making design compromises.

At a time when the sustainability of production processes is under ever-closer scrutiny, the importance of thixomoulding becomes even more acute. “Magnesium is one of very few metals that can be applied to the mould in a thixotropic state.

It is not molten but sheered into particles the size of sugar granules and with some temperature and pressure it takes on the qualities of a liquid. This process cuts down on the energy needed to melt a metal but also reduces pollution as the sulphites and sulphates produced when melting metals are excluded. It is a very clean process.” Magnesium is a very green and sustainable material. It is extracted from different ores and not very intensively at the moment, but it is in huge natural abundance. “A cubic mile of seawater contains 400 million tonnes of magnesium. This can be extracted as a bi-product of desalination processes,” says Maltby.

One big market that Shearline hopes to attract with thixomoulding capabilities is aerospace.

Magnesium is one third lighter than the aluminium typically used in aircraft production today and while it may not be a suitable material for high load-bearing parts yet, there are myriad parts and casings in aircraft, many of which are made from aluminium and machined from solid which could be exchanged for less energy intensive, lighter magnesium alternatives.

Additive layer manufacturing at a glance
Products are built layer-by-layer using a precision laser to melt a powdered substrate either of metal or plastic. The laser builds the product working directly from CAD data with no need for moulds or casting.

Multiple products for different parts and customer orders can be created in the same machine run and adjustments can be made to the design of products between runs with ease.

The process is energy intensive but efficient in materials consumption and can create high efficiency savings in the lifecycle of a product through material optimisation and weight reduction.

Research has shown that reducing the weight of an aircraft by 100kg using additive manufacturing structures would save approximately 4.5million litres of fuel over the lifetime of the aircraft, equating to one million tonnes fewer CO2 emissions. For an airline operating 30 long-haul aircraft this would mean saving £2.5m per year (data courtesy of Exeter University).

The UK is currently a world leader in terms of additive manufacturing capability and capacity, but funding is limited and 3T’s average lead time between expression of interest in DMLS potential and production of parts is two years.

Printed electronics
Not all advanced manufacturing methods have to include disruptive shifts in technology. Some of the most exciting possibilities in manufacturing are inherent in capabilities that the UK already has strengths in.

An example is the printed electronics industry.

The implications that the development of this industry could have for a whole range of sectors is staggering. Terry Watts, CEO of Proskills, the Sector Skills Council for the process and extractives manufacturing sector, says: “The process for printed electronics is pretty consistent with standard printing, but instead of printing ink you print circuits; potentially quite sophisticated circuits. I have seen solar panels being printed and even a television, but there are more mundane applications such as printing lights into wallpaper.

Much research is going into the types of substrates companies can use to print on. These are mainly fabrics at the moment, but it is possible to print onto paper, plastics and ceramics. “Critically, the technology you use to print electronics is the same as you would use for magazines and newspapers. Without too much cost or upheaval you can turn a normal litho printer into a machine for printing solar panels,” adds Mr Watts.

“Academia claims that the UK is the absolute world leader in this technology and according to international benchmarks Britain has the strongest printing industry in Europe, so this could potentially have a very big impact on the economy.” The obstacle to seizing this lucrative opportunity, as with additive manufacturing, is awareness, says Watts. “The technology is not widely known about among printers and the supporting supply chain. Even the trade bodies seem under-informed, so Proskills is working hard with academia to educate our sector.

It is a common problem that in the UK we are often world leaders in understanding new technology, and in driving research into its application, but not in converting that into production capability.”

The smart road ahead
Smart production processes have many enthusiastic champions in the UK. Among these is Sir James Dyson, who in March this year produced an extensive report for the Conservative Party on the importance of R&D and forward-looking technologies to the strength of British industry and the UK economy’s ability to recover from recession.

Mr Dyson’s report, Ingenious Britain, states that “for advanced economies with relatively high labour costs, producing standard products using standard processes would not sustain competitive advantage.” Sluggishness from some organisations in opening their eyes to new technologies and the education channels around them is, arguably, holding British industry back. Meanwhile the cost of the new generation of smart techniques must not be discounted.

Cash for investment is thin on the ground and lack of financial confidence among SMEs due to sluggish bank lending and uncertainty over the reliability of government funding streams is a problem. However, through collaboration, exploiting tax credits and partnering with universities, research centres and larger industrial enterprises, it is possible to explore how the latest technologies and skills sets could transform companies’ competitive scope.