Rebalancing the economy will need refurbished industry

By the end of the last century, the UK had seen decades of Government overemphasis on the services sector to the detriment of manufacturing.  Machinery design has changed beyond recognition compared to some of the assets that are still being repaired today, albeit at an increasingly punitive energy cost.

But things do show signs of change; electromechanical actuation is beginning to replace hydraulics and pneumatics on the factory floor. It is over ten times more energy efficient than pneumatic actuation and over four times more efficient than hydraulic actuation. It is also less noisy and has fewer emissions and leaks, which fits in with the environmental targets set by the Government and the EU.

Pneumatic systems use air even when actuator motion is not required, while electric actuators only use energy when it is needed. The longer the dwell cycle between moves, the higher the energy savings. Furthermore, air-lines and seals wear and split due to contamination and ageing, and so need constant maintenance and replacement, often requiring many man hours and headaches to repair the kilometres of hoses. This translates not only to unreasonably high energy costs but increases the overall maintenance expenditure.

Crucially, it is very difficult to get repeatable constant air pressure, because cylinders running on the same compressor are always switching on and off around the factory. In contrast, electric cylinders always give repeatable results. This is critical in plastic sealing applications, for example, to avoid scrap. Although the initial cost of an electric actuator is potentially more than three times more that of a pneumatic actuator, if sized correctly the extra capital cost is guaranteed to be paid back within 12-18 months.

Electric linear motion is a clean technology, and hence it is preferred in many industries like food, water, medical device manufacture, pharmaceuticals, defence and aerospace. Furthermore, health and safety regulations state that machines should operate below 85 decibels at a distance of one metre (85dbA@1m). Electric actuators are much quieter than pneumatics ones and thus fitting them helps manufacturers comply. Keeping noise down helps morale on the shop floor the work force to be happier and reduces insurance premiums.

In 1999 Milacron published a study that discussed the rationale for its all-electric injection moulding machines. It illustrated the advantages of digital electro-mechanical actuators over the hydraulic motion control systems that the industry traditionally used.

The vast majority of new injection moulding machines is sold as ‘all-electric’, and many are being retrofitted to gain the benefits. By completely eliminating the possibility of oil leaks, Milacron found that electric actuation became the obvious choice for medical, electronic and clean room applications. Furthermore, noise levels on Milacron machines dropped over 30%, with energy savings of 75%.

So if even they are fixing what ain’t broke, perhaps you should start thinking about doing exactly the same thing. Not every old adage is a wise one.