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TC A490 bolts / washer & nut reuse?

TC A490 bolts / washer & nut reuse?

TC A490 bolts / washer & nut reuse?

(OP)
Have a condition that requires the replacement of 400 A490 1" TC bolts.  Upon removal the nuts and washers will not be in as-manufactured condition (clean/lubricated) so they can not be reused, correct?


Specification for Structural Joints Using ASTM A325 or A490 Bolts

2.3.3. Reuse: ASTM A490 bolts and galvanized ASTM A325 bolts shall not be reused.

RE: TC A490 bolts / washer & nut reuse?

That is what it says. You could re-use them as A307 bolts but not as high strength.

Michael.
Timing has a lot to do with the outcome of a rain dance.

RE: TC A490 bolts / washer & nut reuse?

You can not re-pretension A490 bolts.  As TC bolts with button heads it would not be possible to re-install the bolts anyway.  

http://www.FerrellEngineering.com

RE: TC A490 bolts / washer & nut reuse?

Aren't the nuts and washers covered by the same specification for both A325 and A490?  And since a black A325 can be re-used provided the nut can run up the bolt by hand, I would think the nut and washer reuse could follow the guideline, even for A490 bolts.  But this is just my opinion as I can't find anything definitive in the code.   

RE: TC A490 bolts / washer & nut reuse?

I was wondering how one would re-install a TC bolt...the ones I have seen had button heads.

RE: TC A490 bolts / washer & nut reuse?

Heavy hex nuts and washers are under a different specification, though referenced in the "Specification for Structural Joints Using A325 or A490 Bolts".  A325 and A490 apply to the bolts only.  There is one exception....Galvanized A325 high strength bolts and nuts are considered an assembly, and are to be used together.  Those cannot be re-used. A490 Bolts cannot be re-used.  High strength nuts and washers can be re-used, except in the case where they are considered an assembly, as noted for galvanized bolts/nuts.

RE: TC A490 bolts / washer & nut reuse?

I think boffintech was asking about reusing the nuts and washers, not the actual bolts.

If that is the case, I see no problem if, after a visual inspection no problems are detected. The no reuse rule has to do with the plastic elongation and hence property change on the bolt shaft, not the nut or washer

RE: TC A490 bolts / washer & nut reuse?

(OP)
Sorry if I wasn't clear.

The bolts are being removed and discarded.

I was curious about the  nuts/washers.  Are the TC bolts, washers, and nuts an assembly?  By the time they are removed the factory lubricant will have been significantly removed.  If the nuts/washer were reused the components would have varying degrees of lubricity so how would I be able to perform the required pre-installation tests?

RE: TC A490 bolts / washer & nut reuse?

They come as a package, bolt, nut and washer.

If you were to try to re-use the old nuts and washers, you would have to break some extra new bolts with old nuts and washers in a Skidmore to see if the installed tension is within range. By the time you do this, you'd probably be better off just replacing them.

Michael.
Timing has a lot to do with the outcome of a rain dance.

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