Identifying Bolt from Head Markings

[MWD123]

Hi, I'm investigating an existing building and have come across some bolts stamped "SS L393/1 GS M", does anyone know what this refers to?

In the UK I'm used to seeing standard markings like "M8.8" of "A4-70" but I've never seen this sort of thing, I assume it's a non-european standard.

Any help would be appreciated

 

[desertfox]

Hi MWD123

This link might help:-

https://www.fastenerdata.co.uk/technical/technical-data/head-markings.html#M

“Do not worry about your problems with mathematics, I assure you mine are far greater.” Albert Einstein

 

[MWD123]

Thanks desertfox, unfortunately no luck with the info on that page.

To add context, this is a structural bolt in a steel framed building, I would expect it to be carbon steel (typical for this environment) and it is a hex head, approx size M20.

 

[electricpete]

SS might be stainless steel (which I realize you don't expect, but you never know).
Try permanent magnet test. If it doesn't attract, almost certainly stainless. If it does attract, somewhat inconclusive (some SS does attract)



=====================================
(2B)+(2B)' ?

 

[FacEngrPE]

You might be looking at someones "special bolt", with a part number rather than a proper head marking.

 

[chicopee]

Have you had a chance of studying the original drawings from the builder? Also certs are required on such projects, see if they are still available from archives maintained presumably by jurisdiction authorities.