Gary Nolan writes:

>I have a few projects I am working on and have some questions to ask. I hope
>someone has some ideas better than mine.

[items 1/2 snipped...]

>3). Real hard problem -
>    Our main product is rails for the railway, each rail has its
>    own id (like a serial number but more complex), and traceability
>    of each rail through the plant is very important. What we would
>    like to do is attach a barcode to the rail as the rail id is
>    stamped into the rail. This would allow us to use automated
>    scanning of rails through the mill. The problem is the temperature
>    of the rail at stamping time is 1700 degrees (red hot). Anybody
>    have an idea on how to apply a tag. You cannot make any marks
>    on the rail (considered a defect) and you cannot rivet to the
>    rail (creates a possible stress point).

Here are some ideas (pilfered from others):

1. Tack weld (silicon bronze) the id (imbedded on a small part). This
   could be easily removed (hand grinder) at the end of the mill
   without creating any stress points.

2. Consider using a high temperature adhesive (silicon glue) like RTV.
   High temp RTV should withstand these temperatures.

3. Recent studies have shown that you can fill a small hole with an
   oversized ball bearing (with force) such that the result is actually
   stronger (a cold roll effect is created). You might be able to use
   this idea to create an anchor point for the tag.

4. A lot of rails in the us have grounding points that are used to attach
   a ground wire between rails. If you have the same system then you might
   already have an anchor point at the end of the rail (these appear to be
   welded attachments).

Duane Percox ([log in to unmask]  v/650.306.1608 f/650.365.2706)
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