The cold upsetting steel is produced by hot metal pretreatment - LD- ladle argon stiring process. It is obtained that the multi- elements compound inclusions in steel lead to cold upseting crack of steel based on analysis of structure and inclusions of cold upsetting crack of 0.23C-0.69Mn steel for rivet by scarning electon microscope and energy dispersive x- ray spectometer. With increasing ladle bottom blowing argon pressure from 0.3 MPa to 0.6~1.0 MPa

modified original blowing argon procedure - soft blowing argon after Ar stiring for 1 min and total blowing argon for 3 min to impruved blowing argon procedure - soft blowing argon after Ar stiring for 3 min and total blowing argon for more than 6 min

and improving baking process for tundish to decrease inclusion MgO

the cold upsetting crack of steel for rivet was effectively avaided.