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Re: A490 bolts

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........"If your structure is inside a building then the bolts probably
do not need
to be coated at all......"

This could become a very MISLEADING issue.   I've seen and heard this
Some engineers assume that if inside a structure corrosion doe's not
occur and
therefore are becoming very ignorant.   Statements such as above may
misleading, especially, if the inside of a structure that produces a
corrosive environment
such as: manufacturing and chemical plants, theme park flumes, etc.

Desi J. Kiss, PE

On Wed, 16 Oct 2002 07:19:14 -0700 THunt(--nospam--at) writes:
> Javier,
> The reason A490 bolts can not be galvanized is due to the 
> possibility of 
> hydrogen embrittlement.  This is a concern when tensile strengths 
> approaches 200 ksi.  A490 bolts are specified at 170 ksi but due to 
> manufacturing variances it was close enough to incorporate the 
> restriction.
> If your structure is inside a building then the bolts probably do 
> not need 
> to be coated at all.  If your structure is outside and the steel is 
> galvanized then I would switch to A325 bolts which can be 
> galvanized.  If 
> your structure is outside and the steel is being painted then the 
> A490 
> bolts can be spot painted after installation.
> As a general comment, I would say you should be careful when 
> specifying 
> A490 bolts to make sure that the sizes you are specifying are 
> readily 
> available especial in remote areas and countries.  There is also a 
> concern 
> that if you are using both A325 and A490 bolts and your construction 
> team 
> is suspect then there is a possibility that they could be 
> mis-installed.
> Thomas Hunt, S.E.
> ABS Consulting
> "Javier Encinas" <jencinas(--nospam--at)>
> 10/15/2002 06:19 PM
> Please respond to seaint
>         To:     <seaint(--nospam--at)>
>         cc: 
>         Subject:        A490 bolts
> Does anybody know why galvanizing A490 bolts is not allowed? Also, 
> what 
> measures are usually taken to protect these bolts against corrosion?
> Javier Encinas
> Encinas & Associates



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