Heat number identification on steels plates 1

[rbrez]

The following heat number / identification markings were taken off some steel plate. Can anyone help me identify it?

75A679 287993 AAR-TC 128GRB USS

I recognize the material - AAR-TC128 GRB.
I think the Mill is US Steel
I'm not sure of the meaning of the digits of the first two number groupings.

Thanks

 

[lostsailor]

rbrez,
Do you have a material test report by any chance? I believe you have correctly identified the mill. It is possible that the first two number groupings constitute the heat number although it is possible that the 75A679 is a reference to the 1975 edition of ASTM specification A679 for high tensile, cold drawn steel wire, although I see no reason this would appear on plate. Are these the original mill markings? Where did you procure this material from and what is the intended fabrication/service?
Regards,
RLS

 

[rbrez]

Thanks for the reply. That is the problem, I do not have the Mill test reports. I agree that the 75 could be the year. The plate TC 128 GRB is a special plate used in the railcar tank building industry. I am just trying to find out what the code markings mean.

 

[Carburize]

Contact US steel QA department.