"Schertz, William W." wrote:

Paul,
One thing folks working on engine assemblies should be aware of is the
possibility of counterfeit bolts, that are sold as grade 8 or grade 5 but
have much lower strength characteristics.

As an example, at work a technician dropped a bolt, and the head dented.  We
checked and it was indeed one of the suspect bolts - and we found a number
of them in the assembly.

I am enclosing a PDF file which has head marking identification. I suggest
that people put it up in their shops for ready reference.

William Schertz
Director, Energy Systems Division
630-252-6230
Wschertz@anl.gov

 
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