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EHC Fluids

EHC Fluids

EHC Fluids


I have a number of EHC fluids (listed below) and I would like to determine which ones are able to mix with each other without causing any ill effects/damage (either immediate or over prolonged periods of time). Ideally, I would like a matrix of these fluids where each cell would be either a YES or a NO, depending on whether a combination of two given fluids is acceptable.
I'm looking for useful resources or any ideas as to how to approach this problem. I realize this is a fairly open ended question - any sort of help would be much appreciated.

EHC fluids of interest list:


RE: EHC Fluids

Some of those fluids are mineral oil based, some are phosphate esters.

A web search for each will tell you which is which and they will all tell you that mineral oils must not be mixed with synthetic or ester fluids.

Some of the mineral based fluids are lube oils and some have less zinc and additional stabilisers.

So, even mixing the mineral oil based fluids is not a good idea, if you want reliable system performance.

RE: EHC Fluids

you list a number of fluids based on mineral oils, biodegradable fluids and flame retardant fluids, with different viscosities. the biodegradable fluids may be mixed with mineral oils, but the result cannot be classified as biodegradable unless only a small amount of mineral oil is mixed with a lot of biodegradable fluid. the fire resistant type of fluids cannot be mixed with mineral oils or biodegradable oils and may also cause a lot of problems with seals not designed for use with those fluids.

generally speaking fluids of quite different composition and suggested application should not be mixed because in the long run you will most likely end up with more wear, corrosion and other forms of machinery failure.

a more useful approach would be to clearly identify in which machinery which fluid is recommended. that might show some scope to reduce the amount of fluids needed, so that after changing the fluids in use you could end up with a smaller number of fluids that would maintenance somewhat easier.

however, before doing so, you should familiarize yourself thoroughly with the characteristics of all the fluids involved to avoid unpleasant surprises.

RE: EHC Fluids

Every cell in your matrix should be marked NO.
... especially if any of your machinery is under warranty or service contract.
... and even just on general principles.

If you end up with the 'wrong' fluid in some machine, or some mixture of fluids that individually would be okay but somehow interact with each other, producing excessive wear or seal failures, well, WHO YOU GONNA CALL?

A better strategy would be to 'standardize' on the fluids you now use, and demand that any new machinery be warranted to operate satisfactorily on one of those standard fluids.

... and to add signage or color or other indicator to the various fill points, and implement some clear internal systems with discipline to make sure that the right stuff always goes in.

Mike Halloran
Pembroke Pines, FL, USA

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