Unintentional mixing of Exxon Polyrex EM with Royal Purple Ultra-Performance #2

maciasjj
During maintenance of the equipment there is a probability of mixing of various greases. Some greases mix up between themselves without properties deterioration. Others greases are incompatibled. Consequences of mixture can be unpredictable. Mixes of greases can form resins, become hard or become thin, etc. It is necessary to use grease manufacturers recommendation - no mix different greases! Base oils and/or thickeners can have incompatibility. In our case an element of incompatibility will be thickeners - the aluminium complex is incompatible with polyurea complex. In order to prevent undesirable consequences or failure it is better to stop this unit, carefully clean it as far as possible and anew to fill fresh grease. Though on the other hand, it is interesting what will happen with this mix further?
Mikhail

To avoid cross contamination of greases can be avoided by using differing grease fittings. By using a combination of standard, and both sizes of buttonhead fittings you can have 3 different unique fittings that will help avoid cross contamination. Only the grease gun with the correct lube can be used on a particular piece of equipment.

If the component that received the inappropiate grease is a critical piece of equipment or of high maintenance or loss of production cost, I would recommend contacting a reputable laboratory and having a compatiblity study conducted. Otherwise, you are in uncharterd territory and it is best to not guess or hope that nothing adverse will happen to the machine.

If possible, I would recommend performing maintenance to clean out all of the grease mixture and start over with the lube of choice and provide measures to prevent reoccurrence. It might even be worthwhile to change out the bearings, based on the type and mission of the component for peace of mind.

I suspect that you could have a compatiblity study performed for less money than the maintenance of the machine, depending on the urgency of the situation.

Good Luck.

If you wanted to do a compatability study in house you can take a 50-50 mixture of the two greases and mix them well in a container and then allow them to sit for three days and then re-examine them for a texture change. Let me know what you find. If you want to accellerate the test allow the mixture to sit for in an oven for four hours at 160 degreed F. This is a quick in house technique to use that will give pretty reliable results without going through lab ($$) testing, however you will find that polyurea and aluminum complex dont mix very well.

according to my compatiblity chart these two greases if i am correct a aluminum complex and a polyurea are not compatible.this compatiblity guidelineis by myers NLGI spokesman.it is quite old 1983 and a lot of things have changed since then.

The Royal Purple product guide lists a standard grease compatibility guide which shows PolyU incompatible with Alum Complex. However there is another table for Ultra-Performance grease which lists it as fully compatible to 225F, and only fully incompatible above 350F.

The claim is Ultra-Performance grease is more pure and stable.

If you use RP the product guide is a must. It is actually helpfull no matter what you use.

Hey MassEng, is the Royal Purple product guide available as a downloadable documnet from the net? If so have you got a link?
Thanks.