Stainless Steel and Anti-Galling Lubricants 4

[stevenpf]

I am trying to determine if Colloidal Graphite in Isopropanol (MIL-L-24131) [CGI] can be used with stainless steel to prevent thread galling.

I must follow the guidance in NSTM [Naval Ships Technical Manual] CH 075 but it is unclear whether the use of CGI must be limited to stainless steel in applications <1000 deg.F or whether CGI should not be used at all with stainless steel.

I have tried numerous internet searches but have not been able to find clarification regarding this specific issue. Even if you are not familiar with the specific military references, any information/experience in private industry would be appreciated.

 

[Metalguy]

Seems like very few things can prevent galling of SS like 304/316. Graphite is only a so-so dry lube anyway. If you are able to change the SS then consider something like Nitronic 60.

 

[unclesyd]

The 1000°F is upper temperature limit due to the oxidation of the graphite. MoS2 has various upper limits from 700°F-850°F depending on its use.

A better anti-seize would be one based on Boron Nitride, White Graphite. We used this type lubricant very suscessfully on S/S and Ni alloys at 1250°F. Our specification was to use this material above 900°F.

Also the silver base lubricants worked better at your temperature than the copper based ones.

 

[stevenpf]

unclesyd,

Thanks for the info. I need to be able to formally reference the info you passed along- now that I know why colloidal graphite is not used for high temperatures, do you know where I can find that info, either on-line or a reference book?? Thanks

 

[CoryPad]

stevenpf,

You should perform a site search here at Eng-Tips for this subject as it has been covered extensively. For example, this thread:

thread404-32366

has good references. Look at everything posted by member Kenneth.


Regards,

Cory

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[Metalguy]

Way back in the 1970's I was working with superalloys, and one of the tests we ran for hi-temp. coatings involved a kerosene-fueled &quot;burner-rig&quot;. Small test bars were installed in a rotating holder and secured with a superalloy screw-about 5/16&quot; dia., IIRC. The screws were dipped in regular (not mint flavored) Phillips milk-of-magnesia, which was the only thing found that would allow their removal after everal hundred hours of running at ~1,200 deg. F (screw temp., test bars were running up to ~2,200 F.).

 

[LBlount]

Steve,
I posted a solution for galling in another thread. thread338-52413 Galling on stainless steel thread under seawater condition. Try there!

LeGrande

 

[unclesyd]

Metalguy,

I'll bet you used &quot;Sloan's Liniment&quot; as penetrating oil too.

 

[Metalguy]

Unclesyd,

Never heard of Sloan's. I also learned that the last thing to use on those screws was any kind of pene. oil-they would always seize and break right off when I tried to loosen them if I tried oils. However, for some reason I can't remember I never tried one of the nickel anti-seize compounds. The MgO worked well enough, and I had a big supply of screws.

IIRC the threaded holder was N-155, but I can't remember what the screws were-other than expensive.

 

[unclesyd]

Metalguy,

Sloan's was a liniment that had an oil of wintergreen base.
Oil of wintergreen is very good penetraing oil as it has a very low surface tension. I first saw it used on AC steam turbine casing bolts.

We had thousands of B-7 bolts that had to undone while cooling from 600°F during an overhaul. To faciltate there removal the bolts were DAGed(collodial graphite) prior to installation. It was found that the application of a little penetrating liguid (Sookie, SPS, etc.) would faciltate thier removal. On S/S we used a copper based lubricant and usually had no problems.

 

[unclesyd]

Here is the BN lubricant(Thermoplate 210) we used with excellant success with S/S and Ni alloys above 900°F. It was very effective at 1200°F with 316 S/S and Inco 718.

http://www.socousa.com/showprod_detail.asp?pid=8O4&type=cat&id=1&prid=102

 

[punh3]

what you are looking for is called neolube.

 

[Metalguy]

Punh3,

IIRC Neolube is graphite in acetone or alcohol, and Unclesyd has already pointed out it's temp. limit.

From use at our plant we also learned there are better antisiezes for 600 deg F.