Hello everybody,certainly all of you know, that the ST in front of a screw description indicates the thread diameter of the screw, for example:ISO7049-ST5,5x32So we have a pan head tapping screw with a diameter of Ø5,5 and a length of 32 (data in millimeter).The ST stands for self tapping, right? I can't find any standard or something else, where I can find this information...Somebody knows, where I can find it?

Hello rzhz, if you search "ISO 7049" on the internet you will find catalogues for this and it's giving an equivalent towards DIN 7981 C.What is the precision needed, can't you just scale one ? 
philippe JOSEPH2018-04-18 10:38:39

You can try at TRACEPARTS but you will have to check the dimensions for safety.

I want to know if there is any standard for the abbreviation "ST" for "SelfTapping" :)

OK rzhz I don't have access to the norms ISO 7049 ( DIN 7981 ) but from what I see at any screw seller it looks like ST is OK for Self Tapping and the callout that you use : ISO7049-ST5,5x32 seems perfectly correct, kein Problem. 

I think it may stand for Square Thread, as opposed to Acme or Unified or other profiles, e.g. at https://en.wikipedia.org/wiki/Square_thread_form.
Kent Cooper2018-04-18 19:56:15

Hmmm, I'm not quite sure if this is right. The thread of ST screws is sharp, the one you've found is quadratic...

Yes and ISO7049-ST is not a Square Thread.