It can come to bursts at the wire surface of cold upsetting
steels by the compressing to screws or tools. The strength of the bursts is dependent
from the degree of the cold forming, the size of the existing defects and possible
anomalies of the structure. Small rolling defects were the reason for the processing
problems in this case.
19,00 mm round - spheroidised , pickled
following compressed to screws , quenched and tempered