Smooth operator

In a bid to re-write the tribology rule book, a UK company has developed a lubricant claimed to both monitor and improve equipment condition. Mark Venables reports.

Traditionally sensors — including vibration and acoustic — have been used to monitor the condition of plant and deliver information about the machinery.

Now Peter Dryden, of East Sussex company Hydralube, claims to have invented a system that not only checks on the condition of the machinery but helps it run more efficiently, thereby extending its life.

His company has developed a lubricant called Hydrodynamic Plasma, which works by reducing the contact and friction between metal surfaces.

Hydralube has been in business for 20 years and believes its technology, which incorporates a computerised asset monitoring system, may revolutionise the approach to wear in modern machinery. It has spent the last five years developing the lubricant in a project led by Dryden, a tribologist.

‘If you take an old lubricant out of a gearbox and replace it with a new one, your performance would improve but it wouldn’t actually improve worn surfaces,’ said Dryden.

He says his formulations contain a molecular membrane that is implanted in the components to act as a barrier coating. This has the ability to absorb heavy stress loading and shockwave phenomena — a major cause of metal fatigue and premature asset wear.

The lubricant is formulated from synthetic food-grade materials that are compatible with mineral hydrocarbons, most types of synthetic oils and greases and commonly-used seals and materials.

It also meets the requirements of the Food Standards Agency and The Food Safety Act 1990, so is suitable for use in the food manufacturing industry, where the company has already won customers.

In one application, Dryden claimed the lubricant was able to save a leading confectionery manufacturer £10m of costs normally associated with energy consumption, wear and other costs attributable to machine down-time.

Hydralube claims to be able to extend the working life of new or worn assets by at least a quarter. It says much of the guesswork can also be taken out of lubrication regimes, and schedules can be developed that exactly match the demands of the machines being monitored.

Each asset within a production environment is given an asset tracking number and a numbered sensor. This information is stored within the software, which will then only show the assets that need attention.

The engineer can then examine the asset and if nothing is obvious, such as looseness or misalignment, he or she simply loads up the recommended lubricant.

Headphones are also attached to the meter so the engineer can listen to the bearings — if lubricant is pumped in and the bearing runs quieter it is a simple indication that more is required.

The computerised asset-tracking module uses an HT meter to show levels of stress and wear. Once these levels are known, the data is fed into the software, which informs the engineer what the actual distress levels — colour-coded green, amber, red and black — are.

So that remedial action is made as simple as possible, the lubricants are also colour coded in a similar fashion so the correct version can be specified and applied for the appropriate wear/stress conditions encountered.

In most cases wear levels can be adjusted up to a lower, less serious wear condition. For example, amber lubricant should take the asset back to a green condition, while red will return it to amber or green.

‘We have a system that measures the wear level of mechanical assets. So the actual meter works with distress acoustic emission and the meter measures in levels of distress,’ said Dryden.

‘If you have a zero to 10 reading then the asset is in good working order; a reading of 11 to 20 means it is starting to degrade; and if it reads 21 to 30 it is in the red which means urgent attention is needed.

‘If it is in the black we can only keep it running for a certain time before it falls over — but it gives staff a chance to change it out.

‘we utilise the pressure that is developed between these surfaces to compound a plasma on to the working surfaces and it forms a micro-build coating which reduces the contact by about 60 per cent — this automatically extends the working life of a worn machine.

‘When the engineer goes round on a programme route and takes readings in numerical order, he or she takes the meter and loads it into the software which analyses all of the possible 1,000 readings.

‘It only displays on the screen the assets that require attention as well as informing an engineer which colour plasma to use to effectively carry out, heal and treat, the worn surfaces.’

As well as combating the never-ending and expensive cycle of install, run, wear down and replace, the hydrodynamic lubricant will also help companies become more efficient by cutting energy consumption.

Cost savings are also realised through greater asset efficiencies and life times achieved using this system, the company claims.

Tests performed by the National Centre for Tribology confirm a reduction in wear and that in some cases the working life of bearings can be extended by as much as 50 per cent — figures also confirmed by tests involving a leading bearing manufacturer.

The reduction in friction also leads to a subsequent reduction in resistance in working machinery, which can equate to energy savings of up to 10 per cent.

Another way the lubricant can save money is through its own lifespan. The fluids last a minimum of seven years, only requiring occasional top-ups. The compounds, on the other hand, last five times longer than conventional greases, meaning that servicing periods can be reduced by as much as 50 per cent.

In other applications, the lubricant has demonstrated savings of up to 17 per cent on the motor-driven gearboxes, which power Archimedean screws.

The company calculates that industry can typically save 5 to 10 per cent on costs.

These savings are compounded by its ability to extend an asset’s working life by as much as 25 per cent, it claimed.