Is there a reliable thread locking compound for over 800 degrees F continuous ? 2

[Tmoose]

The best Loctite says 650 F limit.

There is no room for metal locknuts etc.

These guys' claims are interesting.

http://www.cotronics.com/vo/cotr/pdf/907ts.pdf

thanks

Dan T

 

[EdStainless]

Bent tabs or lockwires.
You can find cements that will work, but you will never get them loose. So any repair will involve cutting them off and replacing them.

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P.E. Metallurgy, Plymouth Tube

 

[MikeHalloran]

Cotronics' ceramic products work pretty much as advertised.

The other choice that comes to mind is water glass, but it's messy.

I'd try real hard to find space for French locks or Stage 8 locks.



Mike Halloran
Pembroke Pines, FL, USA

 

[dik]

If there is any thermal re-cycling, then bent tabs or safety wiring as Ed noted is the only way to go...

Dik

 

[moltenmetal]

Weld.

 

[Tmoose]

Thanks all,

Dan T

 

[AidanMc]

Weld.

The good old Lincoln thread locking...

Aidan McAllister
Metallurgical Engineer

 

[moltenmetal]

Never tried it, but there's a thread sealant called X-Pando which is horrible stuff- can be made to work under some desperate circumstances as a thread sealant, but one side effect it gives is excellent (and undesired) thread locking of the NPT assembly. Might work on a straight thread too, and might be just a little easier to reverse than my previous and more permanent liquid metal suggestion.

 

[NBrink]

Is there room to peen the threads?

Nathan Brink

 

[chessiebear]

i know this is a few weeks old at this point.... how big a nut/bolt? how many? what kind of load are you talking about?

food for thought:

there is an interference thread fit category. its not used much, but its there. you need to HEAT the nut to expand it to the proper thread diameter so that it screws on to your threads. when it 'cools' to the operating temp, it shrinks and wrings on to the threads. when i was a wee tot, we made some custom machine bolts that held together a forging press. we had to heat the nuts to assemble the thing, and had to that right quick too, turn-of-the nut method to make sure we got pretension because no way to do proper torque.

don't forget that mother nature has given us many clever tools to use. sadly we neglect most of them when there funner toys to play with like glues and welds...

 

[EdStainless]

There are also prevailing torque designs that work well.
They simply won't turn in the reverse direction under load.

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P.E. Metallurgy, Plymouth Tube

 

[bcd]

You could go to the old and proven method of Class 5 thread (interference fit).

 

[Tmoose]

thanks all.

Dan T