Shelf Life of Mineral Oil USP (put on cutting burrs before shipping)

[Big Jim]

I'm having a tough time comprehending that the oil sprayed on chips would have a shelf life. It seems like that would be determined in decades or centuries, and insignificant. Is this something that you really need to worry about? Do you even have a need to preserve scrap?

 

[AndyN]

Good afternoon,
I have been trying to find out the shelf life of Mineral Oil USP
We put a small amount on our cutting burrs before shipping.
ISO says for limited shelf life, you must have a procedure.
I can do the procedure, ONCE I know what the shelf life is.
I have searched everywhere, any help would be appreciated.
Thanks!

Don't worry about it. The stuff isn't going to deteriorate in any significant manner and you've probably got bigger fish to fry (not in that oil) than worry about oils. The stuff has been around since dirt, so isn't going anywhere just because it's on your shelf!

 

[AndyN]

Do you even have a need to preserve scrap?

It's a type of tool, Jim. http://images.search.yahoo.com/search/images?_adv_prop=image&fr=ytff1-yff50&va=cutting+burrs

 

[Wes Bucey]

I'm having a tough time comprehending that the oil sprayed on chips would have a shelf life. It seems like that would be determined in decades or centuries, and insignificant. Is this something that you really need to worry about? Do you even have a need to preserve scrap?

When OP uses the term "burrs," he is referring to a special type of tool bit - the most common type of burr anyone would encounter outside of a machine shop would be a dentist's burr used for drilling cavities out of teeth or the crude type in a pepper mill. Sometimes, the word is spelled with a single "r" as "bur."

 

[Big Jim]

Andy & Wes

Of course you are right. Somehow I was thinking he meant another word for chips.

 

[Marc]

I'm having a tough time comprehending that the oil sprayed on chips would have a shelf life. It seems like that would be determined in decades or centuries, and insignificant. <snip>

Even sealed oils do "sour" over time, and it's not decades. How long a given petroleum product is stable depends upon the specific type of petroleum product it is, what environment the container is stored in, what the storage container is made of, whether there are additives in it and other aspects. If it is not in a sealed container "storage life' will typically be shortened (sometimes significantly).

I was involved in a scenario where a company stopped air shipments of a part they made and shipped to Mexico. They were cast iron parts sprayed with a light oil. The shipments were changed from air to ground (railroad) shipment. The light oil did not work on product shipped by train and the company I was helping experienced over 70% rust rejects on the first rail shipment. They had to switch to a heavier oil *and* a special paraffin soaked paper wrap to get rust free shipments through by rail. It was still cheaper than air shipments, all things considered, but it was a significant expense that the company hadn't counted on when they did the cost analysis which they did in planning the shipping method. They didn't save near as much money as they planned.

 

[Big Jim]

Even sealed oils do "sour" over time, and it's not decades. How long a given petroleum product is stable depends upon the specific type of petroleum product it is, what environment the container is stored in, what the storage container is made of, whether there are additives in it and other aspects. If it is not in a sealed container "storage life' will typically be shortened (sometimes significantly).

I was involved in a scenario where a company stopped air shipments of a part they made and shipped to Mexico. They were cast iron parts sprayed with a light oil. The shipments were changed from air to ground (railroad) shipment. The light oil did not work on product shipped by train and the company I was helping experienced over 70% rust rejects on the first rail shipment. They had to switch to a heavier oil *and* a special paraffin soaked paper wrap to get rust free shipments through by rail. It was still cheaper than air shipments, all things considered, but it was a significant expense that the company hadn't counted on when they did the cost analysis which they did in planning the shipping method. They didn't save near as much money as they planned.

Good point. One of my clients showed me a wrapping material that also would have been very effective. It emits nitrogen so that the inside of the package has little or no oxygen and is very effective. I thought the name of it was VCMI paper, but that doesn't work on a google search.

 

[v9991]

I am reading USP~ United States Pharmacopoeia...
since the material is claimed/stated as complying to USP ... the supplier has to provide suitable expiry date OR an re-test period. (this is actually part of their qualification procedures to meet USP standards)

from your end, couple of points have to be in place
1) raw material controls (what is the basis of receipt&approval for usage)
2) determine/define what is the frequency of retest. (to verify the suitability)
3) controls&procedures for disposal of material for which validity has expired.

depending upon the nature of use and application (at end user place)...above controls/procedures could be very simple/minimal or elaborate

hope that it helps.

 

[MIREGMGR]

Re: Shelf life of Mineral Oil USP

It's essentially a petroleum product akin to wax so it should be relatively stable.

This is incorrect, or at least incomplete. Mineral Oil USP contains no anti-oxidants. It will oxidize in contact with air, forming a varnish.

One problem with varnish (oxidized oil) on surgical tools is that some hospital pre-sterilization cleaning processes assume that insufficient time has passed since contamination for oxidation to occur, therefore the cleaning process focuses on hydration and detergent action which may not have sufficient power to cut through varnish. I have less knowledge of cleaning processes in clinical settings such as dental offices where burrs may be used, but I'd assume that they are not likely to be superior to hospital practice.

Another problem with varnish is that, depending on how many water molecules have adsorbed onto it, it can be microscopically very sticky thereby holding contamination.

Mineral oil USP also of course is made up of carbon and hydrogen atoms, and contains no antibacterial functionality since it is USP-pure, therefore supports growth of bacteria that consume lipids. This particularly would be the case if other contaminants were present to provide the additional nutrients, i.e. phosphorus, etc., that a particular bacteria might need.

I appreciate the need to rustproof tools that cannot be made of non-rusting materials, and your goal of using a material that is patient-safe since your users may not have or understand an industrial-strength cleaning process with which to safely remove an "industrial" protective material. I wonder though if your mineral oil USP, after whatever period of time it may be exposed to the environment, remains microscopically sanitary and cleanable.

Even sealed oils do "sour" over time, and it's not decades.

Yes. The "souring" process is bacterial growth. Much less likely in a sealed container of Mineral Oil USP due to the (presumed) purity of the refined oil. Quite likely in free air, though, because of the absence of additives to prevent it.

 

[Marc]

Re: Shelf life of Mineral Oil USP

I think my response was incomplete rather than incorrect. It has been a long time since I had to do anything with my chemistry background so I've forgotten a lot. I wasn't sure if it was an olfin or an alkane as Mikishots said in an earlier post - Mikishots was right: It's an alkane.

So - I just looked it up and there are 3 basic types: Mineral_oil

"Alkanes are not very reactive and have little biological activity. Alkanes can be viewed as a molecular tree upon which can be hung the more biologically active/reactive portions (functional groups) of the molecule."

The question really comes back to how long it is stable, and as I said: It depends upon the environment it is in, as well as what material it is used on. I couldn't find any references which would give me clear information as one would expect for this specific application of mineral spirits. How long it would take for mineral oil USP to turn to varnish (as most petroleum products, including gasoline, will over time) is the significant question. It doesn't happen over night (for example) unless exposed to extreme temperature/humidity. Mineral oil is used to condition "butcher blocks" by some people which is part of why I said it should be "relatively" stable. I use it yearly on one I have which is a bit over 2" thick (part of my kitchen counter) that is close to 45 years old (it came with the house) and no varnish has formed. And while the "souring" process can be in part bacterial growth, it is also part of the oxidation process. While I don't discount bacterial growth, one would think that use on cutting boards would indicate bacterial growth isn't the significant degradation process ("souring") which goes along with the information in Wikipedia ("Alkanes are not very reactive and have little biological activity").

I'm not sure if this discussion thread is in reference to dental or hospital instruments, or metal cutting or wood cutting burr bits. The OP doesn't say. I assumed the OP was referring to metal cutting or wood cutting burr bits.

All your points are valid. I don't dispute them. I believe they add to my earlier posts in this thread.