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I buy aw46 in 250 gallon totes, I have run into a problem with the last 2 totes that I bought, when I sent the oil off for analysis it came back 0 on the silicone.. In fact almost all additives were way down on the chart..The note on my alnalysis sheet said this looked like it was a diluted oil sample..Is there anyway that I can check for silicone before I use the oil with out having to send it off? The totes were "Protect" brand, I also got 2 drums of Nuto 46 that apparently had no silicone in those either, both came from the same warehouse. In the back of my mind I believe someone has put the diluted "Protect" in Nuto drums also..thanks!
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Not all oil types are formulated on silicone antifoam. Some hydraulic oil formulations contains an organic antifoam such as a methyacrylate which is dissolved in the oil as opposed to dispersed in the oil such as silicone antifoam. As it is an organic anitfoam - it does not show up in elemental analysis. My guess is the supplier is using a non silicone antifoam and this is why you are not seeing silicon in the analysis. If you are not having any foaming issues, then why add the silicone antifoam?

ICP-OES can determine if silicon is present in the oil. If it comes back as <1 or 0, then it's quite likely there is no silicon.

If the supplier said that everything is within spec, then I would ask them for typical values in the add pack. Then monitor a number of new oil deliveries to buildup some history and compare to typical values - see if there is much variation. Also talk to the lab to see what variations they have in the measurements taken. For example, it may be that the instrument has a +/- 10% variation so you expect the result to be within this.
Some typical additive values for new hydraulic oil.
Zinc type, typically Zn and P => 300ppm
Zinc free, typically P => 250 ppm, Zn 0ppm
In both cases Ca can be present
Silicon,which is insoluble in oil, at circa 10ppm ppm, this is an antifoam agent and can be achieved in other ways, ie Si can be zero.
Not a good idea to add silicon yourself as you will affect other proerties of the oil.
Can any of you suggest a silicone additive that I may purchase to add to the totes? I do not use this oil in the normal fashion, I use it as a base to a pet medication I manufacture, the silicone acts as a "flow agent" and allows me to pump the medication from the mixing tank to the filler machine, when I use non silicone oil the medication becomes non flowable. thanks!
you make NO sense:
1. Did oil have silicone originally?
2. What is unflowable?
3. does oil/blend you have get foamy? if not what effect does silicone do?
4. i can send you some silicone AF if you want to try it but to mix into a totoe you would have to "cut" the silicone with some mineral spirts then mix in.
5. what exact effect do you think silicone does for you it is only used at perhaps 5-10ppm other than foam it should impart nothing to the oil.
Bruce, the pet medication I manufacture uses aw46 mixed in with powered sulfur, after I mix it together I pump it using a gear pump to a filling machine that fills my bottles. when I receive oil in that does not have silicone added to it, the mixture will not pump into the filler machine..the chemists I have spoken with tells me the silicone makes the mixture flowable,so that the pump will be able to pump it..If I mix it all up with oil that does not have silicone in it and turn on my pump nothing will not pump it. that is why I need to add the silicone to make it where the pump can pump it..thanks!
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