It all depends on the coefficient of friction

There are many products for which it is claimed that they form a friction-reducing coating on the friction surfaces, so reducing wear and fuel consumption. In as far as these really do produce a coating – and there are unfortunately several products which do not – then the effect cannot be any better than the substance(s) used permit.

MoS2 and graphite have been used now for nearly a century. Since 1977 there have been products using low-density PTFE, since 1989 high-density PTFE.

In the last 10 years, there has been an increasing number of products calling themselves “Nano“ or “Ceramic“. Behind these “words of fashion“ often MoS2 or graphite are hidden, but boron nitrate and some strange cocktails also play a role. (We have also come across a product calling itself “ceramic“, in which no useful material at all could be found !)  If a coating is produced, then it will result in a reduction of friction, wear and energy consumption.  But how much is limited and defined by the coefficient of friction of the coating substance.

So, it is important to know the different coefficients of friction.

  Coefficient
MoS2 0,2
Graphite 0,2
„Nano“ > 0,2
„Ceramik“ > 0,2
PTFE with low density 0,04
PTFE with high density 0,02

The time the coating lasts is also important.  We know of a ship-owner who was very unhappy to find that the nano-treatment (at 35,000 Euros per ship), while it did give some benefits, abandoned ship with the first oil change.

One product with low-density PTFE (such as “Teflon“) is indisputably certified to reduce wear by 42% (compared to the same oil, untreated). In the same standard test of the oil industry, with high-density PTFE, “up to 88%“ has been achieved by SX-6000.  If those offering products using materials with higher coefficients of friction were to submit their products to this official test, their results would of necessity be less favourable, which is probably why many prefer wild claims.

Beware too of products which keep their working component secret. And of those which tell you that they do not have any solids, particularly if using  chlorinated paraffin. While it may reduce friction, it can form HCl (hydrochloric acid)  if the chlorine meets condensed water in the motor oil.  This is now an even greater risk, with E 10 petrol producing more water than before.  If such products burn with oil, they produce dioxines in the exhaust, also not really desirable. And they are gone with the first oil change, whatever may be claimed for them.

Ersparnisrechner



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