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We've been running into a lot of problems the last several years with our laboratory Bunsen burners becoming jammed and/or corroded. I've just come to find out that our lab tech has been lubricating the burners with glycerol, which seems wholly inappropriate to me. I guess she figured that if it worked for inserting glass tubing into rubber holes, it would work for anything. To me, something like a WD-40 would seem more appropriate based on household experience, but I'd like to hear if anyone else has found something for this exact application that works well for them.

I'm currently experimenting with white lithium grease. An engineer friend also recommended Permatex anti-seize lubricant. These seem to work well on a very short term, but we'll have to see how it holds up throughout the next several weeks.

Anyone have a favorite lubricant for something like this?

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    $\begingroup$ You're right glycerol is hygroscopic which makes it inappropriate as a metal grease. $\endgroup$ – MaxW Jan 29 '16 at 20:48
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We've been running into a lot of problems the last several years with our laboratory Bunsen burners becoming jammed and/or corroded. I've just come to find out that our lab tech has been lubricating the burners with glycerol.

Does the issue itself seem to have been caused by the glycerol?

Admittedly, we don't use many Bunsen burners nowadays as they're seen as being fairly unsafe in the kind of organic lab I work in where we handle large amounts of solvent, however we do have a well vented hood with several burners in.

The ones we do have are very old indeed (pre 50's) and still work fine without the need for any maintenance (i.e. greasing).

Bunsen burners themselves are incredibly simple pieces of kit, if you do have issues with corrosion (i.e. because of an overly humid environment or harsh chemical vapours), the most sensible thing would be to disassemble, remove the corrosion and re-assemble. The use of any kind of grease should be un-neccesary, especially as very few of them (other than very specialised products) can withstand long term exposure to heat without degradation.

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I think WD40 seems too fluid for this application. A more viscous, greasy lubricant seems more appropriate to me. Also, lithium grease can release flammable vapors based on this MSDS. I'm not sure if that is just the aerosol or if that applies to the residue after application, as well.

I thought Dow-Corning's high vacuum grease was nonflammable and good for high temperatures, but I don't see it listed as being nonflammable. Dow's Krytox (Amazon) seems appropriate, though. It specifically says nonflammable and good up to 200 °C. Depending on what part of the Bunson burner you're applying it to, this may be reasonable. I'm assuming it's the base, where it twists. If that is the case, this area shouldn't get too hot. I'm always able to adjust mine with bare hands while it is burning.

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My thought went to dry lubricants.

There are liquid and aerosol suspensions and dry powder dispensers. Teflon or graphite might work well in your situation if contamination is not an issue. The temperatures are not likely to be a problem. Various silicone oils and greases are also known to handle higher temperatures (cf. vacuum greases in the other answer) but may also outgas and contaminate something one day.

Fitting a brass or other lubricating strip or wear pad in the moving parts may be appropriate for a functional restoration of a treasured vintage burner but replacing the burner may give you a decade of trouble free life if the glycerol lubrication habit is given up.

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