Maintenance re-thought

An atomic power station leads the way.

In many firms, maintenance is in a rut. The maintenance schedules are unquestioned. Innovation is rejected. The firm thus blocks cost reduction, rejecting also increases in productivity and reliability. In today’s competitive world, every penny saved in production is pure gold.

Are maintenance costs "normal" ?

What is "good maintenance"? Asking the maintenance engineer, you will probably be told how important it is to care for the machines exactly according to the maker’s instructions, in time as well as materials. This answer comes apparently without thinking, unaware that it might be possible to do things better.

Ask further "What problems do you have ?" and you will more likely hear that production overtime is irresponsibly jeopardising the maintenance schedule, than that the costs are too high and that certain bearings have to replaced every six months. The costs follow from the schedules, and so are unchangeable. The bearing has always been changed every six months, and last time (one is told with pride) it only cost 15 hours production time to replace.

A nuclear power station shows how.

Fighting costs while increasing productivity is the slogan which has ruled in the USA since the 80s, and which has massively contributed to the economic growth envied in Europe. Fixed procedures are a thing of the past, the only routine is that established procedures and materials are questioned. "How can we do it better ?" "How can we reduce costs ?" "How can we make the machines more reliable and at the same time more productive?" This approach is nothing for yes-men, but it has taken over from the thinking where, previously, play-it-safe and stick-by-the-rules dominated. In one of the world’s biggest nuclear power stations this change in thinking won through in 1989.

Although such power stations are under the same tight safety controls and government oversight as those in Europe, they are owned by public companies. The pressure of the shareholders ensures that the maintenance costs and procedures too are constantly reviewed. Possibilities to simplify procedures and lower costs without reduced safety are researched in depth. Given that there is no safety risk involved, the new procedure is introduced.

Cost reduction with raised productivity.

And just this happened when an engineer of the power station learned about QMI’s products. For nine months various procedures were reviewed against the use of these PTFE products. After the safety question had been resolved, they decided on a total change-over of all lubrication procedures.

The QMI products produce a lasting coating of high-density PTFE (not "Teflon"), which drastically reduces friction. In a standard test of the world oil industry – Sequence III E – the QMI treatment produced a wear reduction of 88%, compared with oil alone. With much lower friction, specific performance is increased, peak temperatures are lowered, wear and energy consumption – and, last, not least – the costs are reduced.

Advantages defined.

The advantages which the power station engineers recognised were set out in an internal memo to justify the change-over. These advantages are worth noting:

"The ultimate bottom line is that the use of synthetic lubrication <PTFE> will save money. The savings will occur as a result of the following:

1. Machines will last longer due to reduced friction and wear. This will in turn mean less capital expenditure for replacement machinery.

2. Reduced maintenance as a result of less wearing out of parts. This means the total labor expense to maintain the machine will be less. The added benefit is of course that it frees up the maintenance technician for other tasks.

3. Better performance. The machine’s ability t resist wear may be evidenced by improvements in ist ability to maintain the tolerance of parts manufactured by the machine.

4. Reduced energy use. As a group, all machines operating more smoothly and efficiently plant wide will need less energy (electricity) to operate.

5. Longer oil life. The addition of synthetic lubricants will preclude the need for as frequent oil change intervals as with natural (petroleum) lubricants. This will free the maintenance technician t perform other tasks.

6. Protection against corrosives. The machine life is lengthened because of coating provided by synthetic lubrication seals the wear surfaces against some types of corrosion which may normally attach non-protected areas."

Since then, many power stations, whether nuclear, water, coal, gas or wind powered, have introduced the use of QMI products. Exact figures are not being registered everywhere, as it is now considered self-evident that the QMI treatment using high-density PTFE must produce benefits.

Experience in China.

Three exceptions in recent years, where the engineers concerned themselves very exactly with the effects of the coating, were in power stations in China. These treatments were seen as showing the way for all Chinese power stations.

In the first power station, the results were measured on four machines. Here, the effect was not only measured in power consumption, but also expressed in financial terms. The pay-back ratio (QMI costs : savings) were calculated most precisely. One kwh was priced at RBM 0.25, about 2 pence. The results in summary:

  1. 750 kw fan. Before 47.8, after 45.6 ampere. Saving 18.29 kwh or 160,220.40 kwh/year. Saving RBM 56,077.14. QMI costs RBM 3,600.00, Pay-back: 1 : 15.58.
  2. 1,800 kw coal grinder. Before 62.13, after 59.6 ampere. Saving 21.02 kwh or 184,222.80 kw/year. Saving RBM 64,477.98. QMI costs RBM 15,060.00. Pay-back 1 : 4.28.
  3. 2,800 kw coal grinder. Before 50.80, after 46.0 ampere. Saving 23.28 kwh or 203,932.80 kw/year. Saving RBM 76,376.48. QMI costs RBM 15,060.00. Pay-back 1 : 4.74.
  4. 3,800 kw coal grinder. Here twice the recommended quantity of QMI treatment was deliberately applied, in order to find out if "more = better". The results lay between those of (2) and (3), which showed clearly that the recommended quantity is correct.

In summary, the power station engineers reported that up to April 1997 they had treated 30% of the machines in the power station at a total cost for QMI products of RBM 845,000. Savings had been registered of RBM 9,519,930. A pay-back rate of 1 : 11.266. After only 30% of the equipment had been treated, the power consumption had been reduced by 5%, and they were looking forward to the savings resulting from treating the remaining 70%, as all the saved power could be sold.

In the second station, four 1600 kw blowers of a boiler were treated. Comparing the power consumption in the month before and the month after treatment, a power saving of 991,488 kw/year was calculated. Pay-back 1 : 6.3.

In the third station, a piston compressor was treated, which had been overhauled shortly before. On full load, before treatment it used 45.57, after 42.50 ampere, so saving 10.2676 kwh or 89,9936 kw/year.

These "pay-backs" are based only on the energy saving. But – and every engineer will understand this – if less energy is required (for the same output), it follows that there must also be less wear. Like in the American power stations, the Chinese engineers are fully aware of this, but only after some years will it be possible to evaluate the reduction in maintenance and spare parts costs, and the gain in reliability, and express these in RBM.

Wide acceptance.

The use of PTFE coatings, whether simply added to the oil, or as grease applied "neat", has gained acceptance not just in power stations. QMI supplies not just the American manufacturing industry – from the steel works of Pittsburgh over the car makers in Detroit through to Silicon Valley - but also service companies, city managements and the oil industry. Even the giant DuPont, which invented PTFE, is among QMI’s customers. Also Disney World, where the toughest cost accountants in America are reputed to sharpen their pencils, lubricates with QMI. The air and space industry keeps its costs under control with QMI products, as for example the armaments giant Lockheed Marietta. In one plant alone, this company takes "on the side" QMI’s air tool treatment for $25,000 per year, $1 per tool. The reserve air tool store needs to hold now 90% less tools in stock !

Depending on the area of application, the benefits and savings are seen differently. In hydraulic systems, for example, users talk not only of less energy and wear, but also of increased performance, as the cooler oil moves the cylinders quicker than warm oil.

Emergency treatment.

Many customers come to QMI first when in despair, saying "what have we got to loose?" Can a hot-running, loud gearbox be kept alive through to the next summer maintenance break ? How can we live with this design mistake ? We cannot afford a new machine until the year after next. The compressor hardly functions any more. The oil consumption is far too high, but we have no time to strip the unit.

Friction is the greatest enemy of things mechanical. If one stays with the established routines, then the "Rabinowitz Law" remains fully applicable. Dr. Ernest Rabinowitz (MIT) calculated that every year 6% of the gross domestic product is lost through wear.

But there is no law saying that this law must be obeyed ! One can fight against it.

The "weapon" is PTFE.

In a five-year study carried out in the late 1980s at Europe’s best-known independent tribological faculty, the Cranfield Institute, it was shown that PTFE offers the way out of the "wear trap".

At Cranfield it was confirmed that the use of PTFE was advantageous in all branches of industry in Europe, this report was given little attention, in the USA it drove the rethinking on maintenance to greater heights. Since then, there is no branch of industry where PTFE is not established.

"But our situation is different", one hears regularly. A leading German car maker once even claimed that "the friction in out engines is different from that in American engines", as if the laws of physics were different on this side of the Atlantic ! But those who have broken free from their old routines have without exception experienced far more benefit than they had initially expected.

Lubricant rationalisation.

A total rationalisation and the change to PTFE-based lubrication requires – and permits – that one re-thinks everything from scratch. With very change, the maintenance intervals and the quantities have to be initially kept under close scrutiny. Operating temperatures are noted, oil samples tested, power consumption monitored, etc. But there should also be a detailed review of the lubricants store.

Through the years, as new machines have been brought in, theses have had their own maintenance schedules and lubricants, as recommended by their manufacturers. The selection of lubricants grows uncontrolled, and also the risk of using the wrong one. And the costs suffer too, as small quantities of many different lubricants have to be purchased. To illustrate the possibility for rationalisation, picture two machines standing alongside each other. One should be lubricated with lubricant X every 1000 working hours, the other with lubricant Y every 12 weeks. If both machines could be lubricated with lubricant Z every 15 weeks, ......

The guarantee at risk ?

In many places, there is the false belief, enthusiastically promoted by the machine and lubricant suppliers, that the use of a not recommended lubricant voids the guarantee. But the only legal definition of the situation throughout Europe is: " In the case of damage which is shown to have been caused by the use of a lubricant which we have not approved, our guarantee performance will be reduced accordingly.

And what matters is the "shown to have been caused", not simply that the product has been used.

Courage brings its reward.

By staying unthinkingly with the established routines, there is no way to achieve a significant saving in maintenance costs, or an increase in productivity. But to declare war against these costs, one must be prepared to throw many products, practices and ideas overboard. Change needs courage.

As the figures from China clearly show, the direct savings (energy) will be different, depending on the nature of the unit treated. In gearboxes, for example, the saving can be between 5% and 15%, depending on just how much friction the design produces. Then the maintenance costs, wages, consumables, spare parts – and the lowered frequency of break-down have to be calculated and added.

The least benefit which can be expected is a reduction of the total costs of 15%. It can be much more. A good reason for a re-think !

Ersparnisrechner



Gearbox | 50,000 miles | Sequence III E | High-density PTFE | Test results | What is an honest test?

Press Release | How to use QMI | QMI in industry | QMI in trucks