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Emerald Group Publishing Limited
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The "flexible" automated manufacturing cell
The "flexible" automated manufacturing cell
Keywords: Robots, Autmation, Plastics
The reports on annual sales of robots in the UK makes depressing reading. Why is it that sales of robots in the UK are poor compared to the rest of Europe and, indeed, the world? Why is it that even in the Far East, where we know labour costs are (in most cases) lower than ours, does the robot population continue to grow year on year at higher rates than in the UK?
UK industry has obviously been through difficult times in recent months and with the threat (reality in some cases) of plant closures, cut-backs in production and job losses, it is easy to understand the low confidence and low investment in new plant that is apparent.
One thing is certain, however – if this dismal trend continues, then so will our manufacturing base continue to decline. We will never return to the "good old days" of being a major manufacturer of goods but we can reduce the decline and (hopefully) achieve some stability by making the very best use of our strengths, skills and resources. No one doubts the creativity, engineering and design skills we have – let us use these skills to maintain our own manufacturing base rather than allow others to benefit from them!
We cannot compete with the low labour rates of emerging Asian and Eastern Europe countries. We will only succeed by being cleverer and smarter. This means developing new technologies and increasing the amount of investment in automation.
In the past we have been successful in automating processes involving high volumes, long runs and few material/tool changes. Investment in automation is relatively easy to justify where the financial return can be spread over many hundreds of thousands (or millions) of parts and months/years of production. Our competitors abroad have also been successful!
In the future we must think about increasing the use of automation of processes where volumes are lower (sometimes very low) and product changes are frequent. A single manufacturing system must be capable of producing a number of quite different products with minimal (ideally zero) downtime for tooling changes etc. The automobile industry is a good example. The most modern car plants are capable of producing a number of completely different models simultaneously on the same production line.
The challenge for us all is to consider how we can apply flexible automation solutions to the industry we each work in.
The plastics injection moulding industry is an example of one sector where "flexible" automated manufacturing cells have yet to be used on a large scale. Less than 10 per cent of plastics injection moulding companies in Europe are currently thought to be investing in this technology.
Automation is not new to the plastics industry – robots have been used for over 25 years on injection moulding machines – mainly to remove products that are either difficult to remove manually or would result in damage to the product if allowed to fall out of the machine under gravity. Automation can also (as in many other industries) significantly improve output and product quality.
Today, most robots used on injection moulding machines are CNC controlled and electrically driven. They are fast and accurate, but most importantly, they are programmable and can easily store any number of programs/routines to perform a multitude of tasks dependent on the product being produced. Combined with relatively simple quick-change gripper head and mould change systems, rapid set up/start up are easily achieved – allowing different products to be changed quickly and frequently, so reducing downtime and inventory levels/storage costs.
It is a sad fact that most robots sold today for injection moulding machines are used for simple "pick and place" applications – even though they are easily capable of handling many more tasks. Downstream operations such as printing, painting, assembly, packing etc. can make use of the same robot (or in more complex systems, additional robots) to allow a range of fully finished products to be produced with minimal handling and labour cost.
For sure, the downstream automation costs may be higher than using traditional "dedicated" equipment, but the ability to respond quickly to new products/design changes will become more important in the future. Only those that invest in flexible manufacturing solutions will be able to quantify the benefits, those that don't are not in a position to do so!
I work for a company that manufactures machinery and automation almost exclusively for the plastics industry. The technology exists now to achieve flexible automated systems. It may not be cheap, but with the improvements in control technology and computing power, it is cheaper now than ever before. My background is totally within the plastics industries so I cannot comment on whether other industries will benefit in the same way – I suspect there are many!